#
d9f28735 |
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06-Dec-2023 |
David Laight <David.Laight@ACULAB.COM> |
Use READ/WRITE_ONCE() for IP local_port_range. Commit 227b60f5102cd added a seqlock to ensure that the low and high port numbers were always updated together. This is overkill because the two 16bit port numbers can be held in a u32 and read/written in a single instruction. More recently 91d0b78c5177f added support for finer per-socket limits. The user-supplied value is 'high << 16 | low' but they are held separately and the socket options protected by the socket lock. Use a u32 containing 'high << 16 | low' for both the 'net' and 'sk' fields and use READ_ONCE()/WRITE_ONCE() to ensure both values are always updated together. Change (the now trival) inet_get_local_port_range() to a static inline to optimise the calling code. (In particular avoiding returning integers by reference.) Signed-off-by: David Laight <david.laight@aculab.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Acked-by: Mat Martineau <martineau@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/4e505d4198e946a8be03fb1b4c3072b0@AcuMS.aculab.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
562b1fdf |
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11-Oct-2023 |
Haiyang Zhang <haiyangz@microsoft.com> |
tcp: Set pingpong threshold via sysctl TCP pingpong threshold is 1 by default. But some applications, like SQL DB may prefer a higher pingpong threshold to activate delayed acks in quick ack mode for better performance. The pingpong threshold and related code were changed to 3 in the year 2019 in: commit 4a41f453bedf ("tcp: change pingpong threshold to 3") And reverted to 1 in the year 2022 in: commit 4d8f24eeedc5 ("Revert "tcp: change pingpong threshold to 3"") There is no single value that fits all applications. Add net.ipv4.tcp_pingpong_thresh sysctl tunable, so it can be tuned for optimal performance based on the application needs. Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/1697056244-21888-1-git-send-email-haiyangz@microsoft.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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133c4c0d |
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11-Sep-2023 |
Eric Dumazet <edumazet@google.com> |
tcp: defer regular ACK while processing socket backlog This idea came after a particular workload requested the quickack attribute set on routes, and a performance drop was noticed for large bulk transfers. For high throughput flows, it is best to use one cpu running the user thread issuing socket system calls, and a separate cpu to process incoming packets from BH context. (With TSO/GRO, bottleneck is usually the 'user' cpu) Problem is the user thread can spend a lot of time while holding the socket lock, forcing BH handler to queue most of incoming packets in the socket backlog. Whenever the user thread releases the socket lock, it must first process all accumulated packets in the backlog, potentially adding latency spikes. Due to flood mitigation, having too many packets in the backlog increases chance of unexpected drops. Backlog processing unfortunately shifts a fair amount of cpu cycles from the BH cpu to the 'user' cpu, thus reducing max throughput. This patch takes advantage of the backlog processing, and the fact that ACK are mostly cumulative. The idea is to detect we are in the backlog processing and defer all eligible ACK into a single one, sent from tcp_release_cb(). This saves cpu cycles on both sides, and network resources. Performance of a single TCP flow on a 200Gbit NIC: - Throughput is increased by 20% (100Gbit -> 120Gbit). - Number of generated ACK per second shrinks from 240,000 to 40,000. - Number of backlog drops per second shrinks from 230 to 0. Benchmark context: - Regular netperf TCP_STREAM (no zerocopy) - Intel(R) Xeon(R) Platinum 8481C (Saphire Rapids) - MAX_SKB_FRAGS = 17 (~60KB per GRO packet) This feature is guarded by a new sysctl, and enabled by default: /proc/sys/net/ipv4/tcp_backlog_ack_defer Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Dave Taht <dave.taht@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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#
c899710f |
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08-Aug-2023 |
Joel Granados <joel.granados@gmail.com> |
networking: Update to register_net_sysctl_sz Move from register_net_sysctl to register_net_sysctl_sz for all the networking related files. Do this while making sure to mirror the NULL assignments with a table_size of zero for the unprivileged users. We need to move to the new function in preparation for when we change SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do so would erroneously allow ARRAY_SIZE() to be called on a pointer. We hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all the relevant net sysctl registering functions to register_net_sysctl_sz in subsequent commits. An additional size function was added to the following files in order to calculate the size of an array that is defined in another file: include/net/ipv6.h net/ipv6/icmp.c net/ipv6/route.c net/ipv6/sysctl_net_ipv6.c Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
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#
b650d953 |
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11-Jun-2023 |
mfreemon@cloudflare.com <mfreemon@cloudflare.com> |
tcp: enforce receive buffer memory limits by allowing the tcp window to shrink Under certain circumstances, the tcp receive buffer memory limit set by autotuning (sk_rcvbuf) is increased due to incoming data packets as a result of the window not closing when it should be. This can result in the receive buffer growing all the way up to tcp_rmem[2], even for tcp sessions with a low BDP. To reproduce: Connect a TCP session with the receiver doing nothing and the sender sending small packets (an infinite loop of socket send() with 4 bytes of payload with a sleep of 1 ms in between each send()). This will cause the tcp receive buffer to grow all the way up to tcp_rmem[2]. As a result, a host can have individual tcp sessions with receive buffers of size tcp_rmem[2], and the host itself can reach tcp_mem limits, causing the host to go into tcp memory pressure mode. The fundamental issue is the relationship between the granularity of the window scaling factor and the number of byte ACKed back to the sender. This problem has previously been identified in RFC 7323, appendix F [1]. The Linux kernel currently adheres to never shrinking the window. In addition to the overallocation of memory mentioned above, the current behavior is functionally incorrect, because once tcp_rmem[2] is reached when no remediations remain (i.e. tcp collapse fails to free up any more memory and there are no packets to prune from the out-of-order queue), the receiver will drop in-window packets resulting in retransmissions and an eventual timeout of the tcp session. A receive buffer full condition should instead result in a zero window and an indefinite wait. In practice, this problem is largely hidden for most flows. It is not applicable to mice flows. Elephant flows can send data fast enough to "overrun" the sk_rcvbuf limit (in a single ACK), triggering a zero window. But this problem does show up for other types of flows. Examples are websockets and other type of flows that send small amounts of data spaced apart slightly in time. In these cases, we directly encounter the problem described in [1]. RFC 7323, section 2.4 [2], says there are instances when a retracted window can be offered, and that TCP implementations MUST ensure that they handle a shrinking window, as specified in RFC 1122, section 4.2.2.16 [3]. All prior RFCs on the topic of tcp window management have made clear that sender must accept a shrunk window from the receiver, including RFC 793 [4] and RFC 1323 [5]. This patch implements the functionality to shrink the tcp window when necessary to keep the right edge within the memory limit by autotuning (sk_rcvbuf). This new functionality is enabled with the new sysctl: net.ipv4.tcp_shrink_window Additional information can be found at: https://blog.cloudflare.com/unbounded-memory-usage-by-tcp-for-receive-buffers-and-how-we-fixed-it/ [1] https://www.rfc-editor.org/rfc/rfc7323#appendix-F [2] https://www.rfc-editor.org/rfc/rfc7323#section-2.4 [3] https://www.rfc-editor.org/rfc/rfc1122#page-91 [4] https://www.rfc-editor.org/rfc/rfc793 [5] https://www.rfc-editor.org/rfc/rfc1323 Signed-off-by: Mike Freemon <mfreemon@cloudflare.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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0824a987 |
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06-Jun-2023 |
David Morley <morleyd@google.com> |
tcp: fix formatting in sysctl_net_ipv4.c Fix incorrectly formatted tcp_syn_linear_timeouts sysctl in the ipv4_net_table. Fixes: ccce324dabfe ("tcp: make the first N SYN RTO backoffs linear") Signed-off-by: David Morley <morleyd@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Tested-by: David Morley <morleyd@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e209fee4 |
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31-May-2023 |
Akihiro Suda <suda.gitsendemail@gmail.com> |
net/ipv4: ping_group_range: allow GID from 2147483648 to 4294967294 With this commit, all the GIDs ("0 4294967294") can be written to the "net.ipv4.ping_group_range" sysctl. Note that 4294967295 (0xffffffff) is an invalid GID (see gid_valid() in include/linux/uidgid.h), and an attempt to register this number will cause -EINVAL. Prior to this commit, only up to GID 2147483647 could be covered. Documentation/networking/ip-sysctl.rst had "0 4294967295" as an example value, but this example was wrong and causing -EINVAL. Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Co-developed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ccce324d |
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09-May-2023 |
David Morley <morleyd@google.com> |
tcp: make the first N SYN RTO backoffs linear Currently the SYN RTO schedule follows an exponential backoff scheme, which can be unnecessarily conservative in cases where there are link failures. In such cases, it's better to aggressively try to retransmit packets, so it takes routers less time to find a repath with a working link. We chose a default value for this sysctl of 4, to follow the macOS and IOS backoff scheme of 1,1,1,1,1,2,4,8, ... MacOS and IOS have used this backoff schedule for over a decade, since before this 2009 IETF presentation discussed the behavior: https://www.ietf.org/proceedings/75/slides/tcpm-1.pdf This commit makes the SYN RTO schedule start with a number of linear backoffs given by the following sysctl: * tcp_syn_linear_timeouts This changes the SYN RTO scheme to be: init_rto_val for tcp_syn_linear_timeouts, exp backoff starting at init_rto_val For example if init_rto_val = 1 and tcp_syn_linear_timeouts = 2, our backoff scheme would be: 1, 1, 1, 2, 4, 8, 16, ... Signed-off-by: David Morley <morleyd@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Tested-by: David Morley <morleyd@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230509180558.2541885-1-morleyd.kernel@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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#
dc5110c2 |
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06-Apr-2023 |
YueHaibing <yuehaibing@huawei.com> |
tcp: restrict net.ipv4.tcp_app_win UBSAN: shift-out-of-bounds in net/ipv4/tcp_input.c:555:23 shift exponent 255 is too large for 32-bit type 'int' CPU: 1 PID: 7907 Comm: ssh Not tainted 6.3.0-rc4-00161-g62bad54b26db-dirty #206 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x136/0x150 __ubsan_handle_shift_out_of_bounds+0x21f/0x5a0 tcp_init_transfer.cold+0x3a/0xb9 tcp_finish_connect+0x1d0/0x620 tcp_rcv_state_process+0xd78/0x4d60 tcp_v4_do_rcv+0x33d/0x9d0 __release_sock+0x133/0x3b0 release_sock+0x58/0x1b0 'maxwin' is int, shifting int for 32 or more bits is undefined behaviour. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: YueHaibing <yuehaibing@huawei.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9804985b |
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14-Nov-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
udp: Introduce optional per-netns hash table. The maximum hash table size is 64K due to the nature of the protocol. [0] It's smaller than TCP, and fewer sockets can cause a performance drop. On an EC2 c5.24xlarge instance (192 GiB memory), after running iperf3 in different netns, creating 32Mi sockets without data transfer in the root netns causes regression for the iperf3's connection. uhash_entries sockets length Gbps 64K 1 1 5.69 1Mi 16 5.27 2Mi 32 4.90 4Mi 64 4.09 8Mi 128 2.96 16Mi 256 2.06 32Mi 512 1.12 The per-netns hash table breaks the lengthy lists into shorter ones. It is useful on a multi-tenant system with thousands of netns. With smaller hash tables, we can look up sockets faster, isolate noisy neighbours, and reduce lock contention. The max size of the per-netns table is 64K as well. This is because the possible hash range by udp_hashfn() always fits in 64K within the same netns and we cannot make full use of the whole buckets larger than 64K. /* 0 < num < 64K -> X < hash < X + 64K */ (num + net_hash_mix(net)) & mask; Also, the min size is 128. We use a bitmap to search for an available port in udp_lib_get_port(). To keep the bitmap on the stack and not fire the CONFIG_FRAME_WARN error at build time, we round up the table size to 128. The sysctl usage is the same with TCP: $ dmesg | cut -d ' ' -f 6- | grep "UDP hash" UDP hash table entries: 65536 (order: 9, 2097152 bytes, vmalloc) # sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = 65536 # can be changed by uhash_entries # sysctl net.ipv4.udp_child_hash_entries net.ipv4.udp_child_hash_entries = 0 # disabled by default # ip netns add test1 # ip netns exec test1 sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = -65536 # share the global table # sysctl -w net.ipv4.udp_child_hash_entries=100 net.ipv4.udp_child_hash_entries = 100 # ip netns add test2 # ip netns exec test2 sysctl net.ipv4.udp_hash_entries net.ipv4.udp_hash_entries = 128 # own a per-netns table with 2^n buckets We could optimise the hash table lookup/iteration further by removing the netns comparison for the per-netns one in the future. Also, we could optimise the sparse udp_hslot layout by putting it in udp_table. [0]: https://lore.kernel.org/netdev/4ACC2815.7010101@gmail.com/ Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bd456f28 |
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26-Oct-2022 |
Mubashir Adnan Qureshi <mubashirq@google.com> |
tcp: add sysctls for TCP PLB parameters PLB (Protective Load Balancing) is a host based mechanism for load balancing across switch links. It leverages congestion signals(e.g. ECN) from transport layer to randomly change the path of the connection experiencing congestion. PLB changes the path of the connection by changing the outgoing IPv6 flow label for IPv6 connections (implemented in Linux by calling sk_rethink_txhash()). Because of this implementation mechanism, PLB can currently only work for IPv6 traffic. For more information, see the SIGCOMM 2022 paper: https://doi.org/10.1145/3544216.3544226 This commit adds new sysctl knobs and sets their default values for TCP PLB. Signed-off-by: Mubashir Adnan Qureshi <mubashirq@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d1e5e640 |
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07-Sep-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Introduce optional per-netns ehash. The more sockets we have in the hash table, the longer we spend looking up the socket. While running a number of small workloads on the same host, they penalise each other and cause performance degradation. The root cause might be a single workload that consumes much more resources than the others. It often happens on a cloud service where different workloads share the same computing resource. On EC2 c5.24xlarge instance (196 GiB memory and 524288 (1Mi / 2) ehash entries), after running iperf3 in different netns, creating 24Mi sockets without data transfer in the root netns causes about 10% performance regression for the iperf3's connection. thash_entries sockets length Gbps 524288 1 1 50.7 24Mi 48 45.1 It is basically related to the length of the list of each hash bucket. For testing purposes to see how performance drops along the length, I set 131072 (1Mi / 8) to thash_entries, and here's the result. thash_entries sockets length Gbps 131072 1 1 50.7 1Mi 8 49.9 2Mi 16 48.9 4Mi 32 47.3 8Mi 64 44.6 16Mi 128 40.6 24Mi 192 36.3 32Mi 256 32.5 40Mi 320 27.0 48Mi 384 25.0 To resolve the socket lookup degradation, we introduce an optional per-netns hash table for TCP, but it's just ehash, and we still share the global bhash, bhash2 and lhash2. With a smaller ehash, we can look up non-listener sockets faster and isolate such noisy neighbours. In addition, we can reduce lock contention. We can control the ehash size by a new sysctl knob. However, depending on workloads, it will require very sensitive tuning, so we disable the feature by default (net.ipv4.tcp_child_ehash_entries == 0). Moreover, we can fall back to using the global ehash in case we fail to allocate enough memory for a new ehash. The maximum size is 16Mi, which is large enough that even if we have 48Mi sockets, the average list length is 3, and regression would be less than 1%. We can check the current ehash size by another read-only sysctl knob, net.ipv4.tcp_ehash_entries. A negative value means the netns shares the global ehash (per-netns ehash is disabled or failed to allocate memory). # dmesg | cut -d ' ' -f 5- | grep "established hash" TCP established hash table entries: 524288 (order: 10, 4194304 bytes, vmalloc hugepage) # sysctl net.ipv4.tcp_ehash_entries net.ipv4.tcp_ehash_entries = 524288 # can be changed by thash_entries # sysctl net.ipv4.tcp_child_ehash_entries net.ipv4.tcp_child_ehash_entries = 0 # disabled by default # ip netns add test1 # ip netns exec test1 sysctl net.ipv4.tcp_ehash_entries net.ipv4.tcp_ehash_entries = -524288 # share the global ehash # sysctl -w net.ipv4.tcp_child_ehash_entries=100 net.ipv4.tcp_child_ehash_entries = 100 # ip netns add test2 # ip netns exec test2 sysctl net.ipv4.tcp_ehash_entries net.ipv4.tcp_ehash_entries = 128 # own a per-netns ehash with 2^n buckets When more than two processes in the same netns create per-netns ehash concurrently with different sizes, we need to guarantee the size in one of the following ways: 1) Share the global ehash and create per-netns ehash First, unshare() with tcp_child_ehash_entries==0. It creates dedicated netns sysctl knobs where we can safely change tcp_child_ehash_entries and clone()/unshare() to create a per-netns ehash. 2) Control write on sysctl by BPF We can use BPF_PROG_TYPE_CGROUP_SYSCTL to allow/deny read/write on sysctl knobs. Note that the global ehash allocated at the boot time is spread over available NUMA nodes, but inet_pernet_hashinfo_alloc() will allocate pages for each per-netns ehash depending on the current process's NUMA policy. By default, the allocation is done in the local node only, so the per-netns hash table could fully reside on a random node. Thus, depending on the NUMA policy the netns is created with and the CPU the current thread is running on, we could see some performance differences for highly optimised networking applications. Note also that the default values of two sysctl knobs depend on the ehash size and should be tuned carefully: tcp_max_tw_buckets : tcp_child_ehash_entries / 2 tcp_max_syn_backlog : max(128, tcp_child_ehash_entries / 128) As a bonus, we can dismantle netns faster. Currently, while destroying netns, we call inet_twsk_purge(), which walks through the global ehash. It can be potentially big because it can have many sockets other than TIME_WAIT in all netns. Splitting ehash changes that situation, where it's only necessary for inet_twsk_purge() to clean up TIME_WAIT sockets in each netns. With regard to this, we do not free the per-netns ehash in inet_twsk_kill() to avoid UAF while iterating the per-netns ehash in inet_twsk_purge(). Instead, we do it in tcp_sk_exit_batch() after calling tcp_twsk_purge() to keep it protocol-family-independent. In the future, we could optimise ehash lookup/iteration further by removing netns comparison for the per-netns ehash. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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e9bd0cca |
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07-Sep-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Don't allocate tcp_death_row outside of struct netns_ipv4. We will soon introduce an optional per-netns ehash and access hash tables via net->ipv4.tcp_death_row->hashinfo instead of &tcp_hashinfo in most places. It could harm the fast path because dereferences of two fields in net and tcp_death_row might incur two extra cache line misses. To save one dereference, let's place tcp_death_row back in netns_ipv4 and fetch hashinfo via net->ipv4.tcp_death_row"."hashinfo. Note tcp_death_row was initially placed in netns_ipv4, and commit fbb8295248e1 ("tcp: allocate tcp_death_row outside of struct netns_ipv4") changed it to a pointer so that we can fire TIME_WAIT timers after freeing net. However, we don't do so after commit 04c494e68a13 ("Revert "tcp/dccp: get rid of inet_twsk_purge()""), so we need not define tcp_death_row as a pointer. Also, we move refcount_dec_and_test(&tw_refcount) from tcp_sk_exit() to tcp_sk_exit_batch() as a debug check. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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9b55c20f |
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18-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
ip: Fix data-races around sysctl_ip_prot_sock. sysctl_ip_prot_sock is accessed concurrently, and there is always a chance of data-race. So, all readers and writers need some basic protection to avoid load/store-tearing. Fixes: 4548b683b781 ("Introduce a sysctl that modifies the value of PROT_SOCK.") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
11052589 |
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13-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp/udp: Make early_demux back namespacified. Commit e21145a9871a ("ipv4: namespacify ip_early_demux sysctl knob") made it possible to enable/disable early_demux on a per-netns basis. Then, we introduced two knobs, tcp_early_demux and udp_early_demux, to switch it for TCP/UDP in commit dddb64bcb346 ("net: Add sysctl to toggle early demux for tcp and udp"). However, the .proc_handler() was wrong and actually disabled us from changing the behaviour in each netns. We can execute early_demux if net.ipv4.ip_early_demux is on and each proto .early_demux() handler is not NULL. When we toggle (tcp|udp)_early_demux, the change itself is saved in each netns variable, but the .early_demux() handler is a global variable, so the handler is switched based on the init_net's sysctl variable. Thus, netns (tcp|udp)_early_demux knobs have nothing to do with the logic. Whether we CAN execute proto .early_demux() is always decided by init_net's sysctl knob, and whether we DO it or not is by each netns ip_early_demux knob. This patch namespacifies (tcp|udp)_early_demux again. For now, the users of the .early_demux() handler are TCP and UDP only, and they are called directly to avoid retpoline. So, we can remove the .early_demux() handler from inet6?_protos and need not dereference them in ip6?_rcv_finish_core(). If another proto needs .early_demux(), we can restore it at that time. Fixes: dddb64bcb346 ("net: Add sysctl to toggle early demux for tcp and udp") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20220713175207.7727-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
12b8d9ca |
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11-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix a data-race around sysctl_tcp_ecn_fallback. While reading sysctl_tcp_ecn_fallback, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 492135557dc0 ("tcp: add rfc3168, section 6.1.1.1. fallback") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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4785a667 |
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11-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
tcp: Fix data-races around sysctl_tcp_ecn. While reading sysctl_tcp_ecn, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d2efabce |
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11-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
icmp: Fix a data-race around sysctl_icmp_errors_use_inbound_ifaddr. While reading sysctl_icmp_errors_use_inbound_ifaddr, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1c2fb7f93cb2 ("[IPV4]: Sysctl configurable icmp error source address.") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b04f9b7e |
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11-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
icmp: Fix a data-race around sysctl_icmp_ignore_bogus_error_responses. While reading sysctl_icmp_ignore_bogus_error_responses, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
66484bb9 |
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11-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
icmp: Fix a data-race around sysctl_icmp_echo_ignore_broadcasts. While reading sysctl_icmp_echo_ignore_broadcasts, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bb7bb35a |
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11-Jul-2022 |
Kuniyuki Iwashima <kuniyu@amazon.com> |
icmp: Fix a data-race around sysctl_icmp_echo_ignore_all. While reading sysctl_icmp_echo_ignore_all, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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4c7f24f8 |
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30-Apr-2022 |
Tonghao Zhang <xiangxia.m.yue@gmail.com> |
net: sysctl: introduce sysctl SYSCTL_THREE This patch introdues the SYSCTL_THREE. KUnit: [00:10:14] ================ sysctl_test (10 subtests) ================= [00:10:14] [PASSED] sysctl_test_api_dointvec_null_tbl_data [00:10:14] [PASSED] sysctl_test_api_dointvec_table_maxlen_unset [00:10:14] [PASSED] sysctl_test_api_dointvec_table_len_is_zero [00:10:14] [PASSED] sysctl_test_api_dointvec_table_read_but_position_set [00:10:14] [PASSED] sysctl_test_dointvec_read_happy_single_positive [00:10:14] [PASSED] sysctl_test_dointvec_read_happy_single_negative [00:10:14] [PASSED] sysctl_test_dointvec_write_happy_single_positive [00:10:14] [PASSED] sysctl_test_dointvec_write_happy_single_negative [00:10:14] [PASSED] sysctl_test_api_dointvec_write_single_less_int_min [00:10:14] [PASSED] sysctl_test_api_dointvec_write_single_greater_int_max [00:10:14] =================== [PASSED] sysctl_test =================== ./run_kselftest.sh -c sysctl ... ok 1 selftests: sysctl: sysctl.sh Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Iurii Zaikin <yzaikin@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: David Ahern <dsahern@kernel.org> Cc: Simon Horman <horms@verge.net.au> Cc: Julian Anastasov <ja@ssi.bg> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Cc: Jozsef Kadlecsik <kadlec@netfilter.org> Cc: Florian Westphal <fw@strlen.de> Cc: Shuah Khan <shuah@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Lorenz Bauer <lmb@cloudflare.com> Cc: Akhmat Karakotov <hmukos@yandex-team.ru> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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bd8a5367 |
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30-Apr-2022 |
Tonghao Zhang <xiangxia.m.yue@gmail.com> |
net: sysctl: use shared sysctl macro This patch replace two, four and long_one to SYSCTL_XXX. Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Iurii Zaikin <yzaikin@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: David Ahern <dsahern@kernel.org> Cc: Simon Horman <horms@verge.net.au> Cc: Julian Anastasov <ja@ssi.bg> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Cc: Jozsef Kadlecsik <kadlec@netfilter.org> Cc: Florian Westphal <fw@strlen.de> Cc: Shuah Khan <shuah@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Lorenz Bauer <lmb@cloudflare.com> Cc: Akhmat Karakotov <hmukos@yandex-team.ru> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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#
65466904 |
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08-Mar-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: adjust TSO packet sizes based on min_rtt Back when tcp_tso_autosize() and TCP pacing were introduced, our focus was really to reduce burst sizes for long distance flows. The simple heuristic of using sk_pacing_rate/1024 has worked well, but can lead to too small packets for hosts in the same rack/cluster, when thousands of flows compete for the bottleneck. Neal Cardwell had the idea of making the TSO burst size a function of both sk_pacing_rate and tcp_min_rtt() Indeed, for local flows, sending bigger bursts is better to reduce cpu costs, as occasional losses can be repaired quite fast. This patch is based on Neal Cardwell implementation done more than two years ago. bbr is adjusting max_pacing_rate based on measured bandwidth, while cubic would over estimate max_pacing_rate. /proc/sys/net/ipv4/tcp_tso_rtt_log can be used to tune or disable this new feature, in logarithmic steps. Tested: 100Gbit NIC, two hosts in the same rack, 4K MTU. 600 flows rate-limited to 20000000 bytes per second. Before patch: (TSO sizes would be limited to 20000000/1024/4096 -> 4 segments per TSO) ~# echo 0 >/proc/sys/net/ipv4/tcp_tso_rtt_log ~# nstat -n;perf stat ./super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000;nstat|egrep "TcpInSegs|TcpOutSegs|TcpRetransSegs|Delivered" 96005 Performance counter stats for './super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000': 65,945.29 msec task-clock # 2.845 CPUs utilized 1,314,632 context-switches # 19935.279 M/sec 5,292 cpu-migrations # 80.249 M/sec 940,641 page-faults # 14264.023 M/sec 201,117,030,926 cycles # 3049769.216 GHz (83.45%) 17,699,435,405 stalled-cycles-frontend # 8.80% frontend cycles idle (83.48%) 136,584,015,071 stalled-cycles-backend # 67.91% backend cycles idle (83.44%) 53,809,530,436 instructions # 0.27 insn per cycle # 2.54 stalled cycles per insn (83.36%) 9,062,315,523 branches # 137422329.563 M/sec (83.22%) 153,008,621 branch-misses # 1.69% of all branches (83.32%) 23.182970846 seconds time elapsed TcpInSegs 15648792 0.0 TcpOutSegs 58659110 0.0 # Average of 3.7 4K segments per TSO packet TcpExtTCPDelivered 58654791 0.0 TcpExtTCPDeliveredCE 19 0.0 After patch: ~# echo 9 >/proc/sys/net/ipv4/tcp_tso_rtt_log ~# nstat -n;perf stat ./super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000;nstat|egrep "TcpInSegs|TcpOutSegs|TcpRetransSegs|Delivered" 96046 Performance counter stats for './super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000': 48,982.58 msec task-clock # 2.104 CPUs utilized 186,014 context-switches # 3797.599 M/sec 3,109 cpu-migrations # 63.472 M/sec 941,180 page-faults # 19214.814 M/sec 153,459,763,868 cycles # 3132982.807 GHz (83.56%) 12,069,861,356 stalled-cycles-frontend # 7.87% frontend cycles idle (83.32%) 120,485,917,953 stalled-cycles-backend # 78.51% backend cycles idle (83.24%) 36,803,672,106 instructions # 0.24 insn per cycle # 3.27 stalled cycles per insn (83.18%) 5,947,266,275 branches # 121417383.427 M/sec (83.64%) 87,984,616 branch-misses # 1.48% of all branches (83.43%) 23.281200256 seconds time elapsed TcpInSegs 1434706 0.0 TcpOutSegs 58883378 0.0 # Average of 41 4K segments per TSO packet TcpExtTCPDelivered 58878971 0.0 TcpExtTCPDeliveredCE 9664 0.0 Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Neal Cardwell <ncardwell@google.com> Link: https://lore.kernel.org/r/20220309015757.2532973-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
fbb82952 |
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26-Jan-2022 |
Eric Dumazet <edumazet@google.com> |
tcp: allocate tcp_death_row outside of struct netns_ipv4 I forgot tcp had per netns tracking of timewait sockets, and their sysctl to change the limit. After 0dad4087a86a ("tcp/dccp: get rid of inet_twsk_purge()"), whole struct net can be freed before last tw socket is freed. We need to allocate a separate struct inet_timewait_death_row object per netns. tw_count becomes a refcount and gains associated debugging infrastructure. BUG: KASAN: use-after-free in inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46 Read of size 8 at addr ffff88807d5f9f40 by task kworker/1:7/3690 CPU: 1 PID: 3690 Comm: kworker/1:7 Not tainted 5.16.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events pwq_unbound_release_workfn Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:lockdep_unregister_key+0x1c9/0x250 kernel/locking/lockdep.c:6328 Code: 00 00 00 48 89 ee e8 46 fd ff ff 4c 89 f7 e8 5e c9 ff ff e8 09 cc ff ff 9c 58 f6 c4 02 75 26 41 f7 c4 00 02 00 00 74 01 fb 5b <5d> 41 5c 41 5d 41 5e 41 5f e9 19 4a 08 00 0f 0b 5b 5d 41 5c 41 5d RSP: 0018:ffffc90004077cb8 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffff88807b61b498 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888077027128 R08: 0000000000000001 R09: ffffffff8f1ea4fc R10: fffffbfff1ff93ee R11: 000000000000af1e R12: 0000000000000246 R13: 0000000000000000 R14: ffffffff8ffc89b8 R15: ffffffff90157fb0 wq_unregister_lockdep kernel/workqueue.c:3508 [inline] pwq_unbound_release_workfn+0x254/0x340 kernel/workqueue.c:3746 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> Allocated by task 3635: kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:437 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:470 kasan_slab_alloc include/linux/kasan.h:260 [inline] slab_post_alloc_hook mm/slab.h:732 [inline] slab_alloc_node mm/slub.c:3230 [inline] slab_alloc mm/slub.c:3238 [inline] kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3243 kmem_cache_zalloc include/linux/slab.h:705 [inline] net_alloc net/core/net_namespace.c:407 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:462 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3048 __do_sys_unshare kernel/fork.c:3119 [inline] __se_sys_unshare kernel/fork.c:3117 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88807d5f9a80 which belongs to the cache net_namespace of size 6528 The buggy address is located 1216 bytes inside of 6528-byte region [ffff88807d5f9a80, ffff88807d5fb400) The buggy address belongs to the page: page:ffffea0001f57e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807d5f9a80 pfn:0x7d5f8 head:ffffea0001f57e00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff888070023001 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888010dd4f48 ffffea0001404e08 ffff8880118fd000 raw: ffff88807d5f9a80 0000000000040002 00000001ffffffff ffff888070023001 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3634, ts 119694798460, free_ts 119693556950 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab mm/slub.c:1944 [inline] new_slab+0x28a/0x3b0 mm/slub.c:2004 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105 slab_alloc_node mm/slub.c:3196 [inline] slab_alloc mm/slub.c:3238 [inline] kmem_cache_alloc+0x35c/0x3a0 mm/slub.c:3243 kmem_cache_zalloc include/linux/slab.h:705 [inline] net_alloc net/core/net_namespace.c:407 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:462 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3048 __do_sys_unshare kernel/fork.c:3119 [inline] __se_sys_unshare kernel/fork.c:3117 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3404 skb_free_head net/core/skbuff.c:655 [inline] skb_release_data+0x65d/0x790 net/core/skbuff.c:677 skb_release_all net/core/skbuff.c:742 [inline] __kfree_skb net/core/skbuff.c:756 [inline] consume_skb net/core/skbuff.c:914 [inline] consume_skb+0xc2/0x160 net/core/skbuff.c:908 skb_free_datagram+0x1b/0x1f0 net/core/datagram.c:325 netlink_recvmsg+0x636/0xea0 net/netlink/af_netlink.c:1998 sock_recvmsg_nosec net/socket.c:948 [inline] sock_recvmsg net/socket.c:966 [inline] sock_recvmsg net/socket.c:962 [inline] ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632 ___sys_recvmsg+0x127/0x200 net/socket.c:2674 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Memory state around the buggy address: ffff88807d5f9e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807d5f9e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807d5f9f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807d5f9f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807d5fa000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 0dad4087a86a ("tcp/dccp: get rid of inet_twsk_purge()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Reported-by: Paolo Abeni <pabeni@redhat.com> Tested-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20220126180714.845362-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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d8b81175 |
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22-Sep-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: remove sk_{tr}x_skb_cache This reverts the following patches : - commit 2e05fcae83c4 ("tcp: fix compile error if !CONFIG_SYSCTL") - commit 4f661542a402 ("tcp: fix zerocopy and notsent_lowat issues") - commit 472c2e07eef0 ("tcp: add one skb cache for tx") - commit 8b27dae5a2e8 ("tcp: add one skb cache for rx") Having a cache of one skb (in each direction) per TCP socket is fragile, since it can cause a significant increase of memory needs, and not good enough for high speed flows anyway where more than one skb is needed. We want instead to add a generic infrastructure, with more flexible per-cpu caches, for alien NUMA nodes. Acked-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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07b85562 |
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21-Sep-2021 |
Mianhan Liu <liumh1@shanghaitech.edu.cn> |
net/ipv4/sysctl_net_ipv4.c: remove superfluous header files from sysctl_net_ipv4.c sysctl_net_ipv4.c hasn't use any macro or function declared in igmp.h, inetdevice.h, mm.h, module.h, nsproxy.h, swap.h, inet_frag.h, route.h and snmp.h. Thus, these files can be removed from sysctl_net_ipv4.c safely without affecting the compilation of the net module. Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
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f9ac779f |
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12-Jun-2021 |
Kuniyuki Iwashima <kuniyu@amazon.co.jp> |
net: Introduce net.ipv4.tcp_migrate_req. This commit adds a new sysctl option: net.ipv4.tcp_migrate_req. If this option is enabled or eBPF program is attached, we will be able to migrate child sockets from a listener to another in the same reuseport group after close() or shutdown() syscalls. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20210612123224.12525-2-kuniyu@amazon.co.jp
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eb0e4d59 |
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19-May-2021 |
Ido Schimmel <idosch@nvidia.com> |
net: Add notifications when multipath hash field change In-kernel notifications are already sent when the multipath hash policy itself changes, but not when the multipath hash fields change. Add these notifications, so that interested listeners (e.g., switch ASIC drivers) could perform the necessary configuration. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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4253b498 |
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17-May-2021 |
Ido Schimmel <idosch@OSS.NVIDIA.COM> |
ipv4: Add custom multipath hash policy Add a new multipath hash policy where the packet fields used for hash calculation are determined by user space via the fib_multipath_hash_fields sysctl that was introduced in the previous patch. The current set of available packet fields includes both outer and inner fields, which requires two invocations of the flow dissector. Avoid unnecessary dissection of the outer or inner flows by skipping dissection if none of the outer or inner fields are required. In accordance with the existing policies, when an skb is not available, packet fields are extracted from the provided flow key. In which case, only outer fields are considered. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ce5c9c20 |
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17-May-2021 |
Ido Schimmel <idosch@OSS.NVIDIA.COM> |
ipv4: Add a sysctl to control multipath hash fields A subsequent patch will add a new multipath hash policy where the packet fields used for multipath hash calculation are determined by user space. This patch adds a sysctl that allows user space to set these fields. The packet fields are represented using a bitmask and are common between IPv4 and IPv6 to allow user space to use the same numbering across both protocols. For example, to hash based on standard 5-tuple: # sysctl -w net.ipv4.fib_multipath_hash_fields=0x0037 net.ipv4.fib_multipath_hash_fields = 0x0037 The kernel rejects unknown fields, for example: # sysctl -w net.ipv4.fib_multipath_hash_fields=0x1000 sysctl: setting key "net.ipv4.fib_multipath_hash_fields": Invalid argument More fields can be added in the future, if needed. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1c3289c9 |
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31-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: convert tcp_comp_sack_nr sysctl to u8 tcp_comp_sack_nr max value was already 255. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7d4b37eb |
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31-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
ipv4: convert igmp_link_local_mcast_reports sysctl to u8 This sysctl is a bool, can use less storage. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
be205fe6 |
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31-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
ipv4: convert fib_multipath_{use_neigh|hash_policy} sysctls to u8 Make room for better packing of netns_ipv4 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
cd04bd02 |
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31-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
ipv4: convert udp_l3mdev_accept sysctl to u8 Reduce footprint of sysctls. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b2908fac |
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31-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
ipv4: convert fib_notify_on_flag_change sysctl to u8 Reduce footprint of sysctls. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b8128656 |
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30-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
net: fix icmp_echo_enable_probe sysctl sysctl_icmp_echo_enable_probe is an u8. ipv4_net_table entry should use .maxlen = sizeof(u8). .proc_handler = proc_dou8vec_minmax, Fixes: f1b8fa9fa586 ("net: add sysctl for enabling RFC 8335 PROBE messages") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Andreas Roeseler <andreas.a.roeseler@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f1b8fa9f |
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29-Mar-2021 |
Andreas Roeseler <andreas.a.roeseler@gmail.com> |
net: add sysctl for enabling RFC 8335 PROBE messages Section 8 of RFC 8335 specifies potential security concerns of responding to PROBE requests, and states that nodes that support PROBE functionality MUST be able to enable/disable responses and that responses MUST be disabled by default Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d24f511b |
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29-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: fix tcp_min_tso_segs sysctl tcp_min_tso_segs is now stored in u8, so max value is 255. 255 limit is enforced by proc_dou8vec_minmax(). We can therefore remove the gso_max_segs variable. Fixes: 47996b489bdc ("tcp: convert elligible sysctls to u8") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4ecc1baf |
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25-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
tcp: convert elligible sysctls to u8 Many tcp sysctls are either bools or small ints that can fit into u8. Reducing space taken by sysctls can save few cache line misses when sending/receiving data while cpu caches are empty, for example after cpu idle period. This is hard to measure with typical network performance tests, but after this patch, struct netns_ipv4 has shrunk by three cache lines. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2932bcda |
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25-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
inet: convert tcp_early_demux and udp_early_demux to u8 For these sysctls, their dedicated helpers have to use proc_dou8vec_minmax(). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1c69dedc |
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25-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
ipv4: convert ip_forward_update_priority sysctl to u8 This sysctl uses ip_fwd_update_priority() helper, so the conversion needs to change it. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4b6bbf17 |
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25-Mar-2021 |
Eric Dumazet <edumazet@google.com> |
ipv4: shrink netns_ipv4 with sysctl conversions These sysctls that can fit in one byte instead of one int are converted to save space and thus reduce cache line misses. - icmp_echo_ignore_all, icmp_echo_ignore_broadcasts, - icmp_ignore_bogus_error_responses, icmp_errors_use_inbound_ifaddr - tcp_ecn, tcp_ecn_fallback - ip_default_ttl, ip_no_pmtu_disc, ip_fwd_use_pmtu - ip_nonlocal_bind, ip_autobind_reuse - ip_dynaddr, ip_early_demux, raw_l3mdev_accept - nexthop_compat_mode, fwmark_reflect Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
97684f09 |
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13-Apr-2021 |
Jonathon Reinhart <jonathon.reinhart@gmail.com> |
net: Make tcp_allowed_congestion_control readonly in non-init netns Currently, tcp_allowed_congestion_control is global and writable; writing to it in any net namespace will leak into all other net namespaces. tcp_available_congestion_control and tcp_allowed_congestion_control are the only sysctls in ipv4_net_table (the per-netns sysctl table) with a NULL data pointer; their handlers (proc_tcp_available_congestion_control and proc_allowed_congestion_control) have no other way of referencing a struct net. Thus, they operate globally. Because ipv4_net_table does not use designated initializers, there is no easy way to fix up this one "bad" table entry. However, the data pointer updating logic shouldn't be applied to NULL pointers anyway, so we instead force these entries to be read-only. These sysctls used to exist in ipv4_table (init-net only), but they were moved to the per-net ipv4_net_table, presumably without realizing that tcp_allowed_congestion_control was writable and thus introduced a leak. Because the intent of that commit was only to know (i.e. read) "which congestion algorithms are available or allowed", this read-only solution should be sufficient. The logic added in recent commit 31c4d2f160eb: ("net: Ensure net namespace isolation of sysctls") does not and cannot check for NULL data pointers, because other table entries (e.g. /proc/sys/net/netfilter/nf_log/) have .data=NULL but use other methods (.extra2) to access the struct net. Fixes: 9cb8e048e5d9 ("net/ipv4/sysctl: show tcp_{allowed, available}_congestion_control in non-initial netns") Signed-off-by: Jonathon Reinhart <jonathon.reinhart@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
648106c3 |
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07-Feb-2021 |
Amit Cohen <amcohen@nvidia.com> |
IPv4: Extend 'fib_notify_on_flag_change' sysctl Add the value '2' to 'fib_notify_on_flag_change' to allow sending notifications only for failed route installation. Separate value is added for such notifications because there are less of them, so they do not impact performance and some users will find them more important. Signed-off-by: Amit Cohen <amcohen@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
680aea08 |
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01-Feb-2021 |
Amit Cohen <amcohen@nvidia.com> |
net: ipv4: Emit notification when fib hardware flags are changed After installing a route to the kernel, user space receives an acknowledgment, which means the route was installed in the kernel, but not necessarily in hardware. The asynchronous nature of route installation in hardware can lead to a routing daemon advertising a route before it was actually installed in hardware. This can result in packet loss or mis-routed packets until the route is installed in hardware. It is also possible for a route already installed in hardware to change its action and therefore its flags. For example, a host route that is trapping packets can be "promoted" to perform decapsulation following the installation of an IPinIP/VXLAN tunnel. Emit RTM_NEWROUTE notifications whenever RTM_F_OFFLOAD/RTM_F_TRAP flags are changed. The aim is to provide an indication to user-space (e.g., routing daemons) about the state of the route in hardware. Introduce a sysctl that controls this behavior. Keep the default value at 0 (i.e., do not emit notifications) for several reasons: - Multiple RTM_NEWROUTE notification per-route might confuse existing routing daemons. - Convergence reasons in routing daemons. - The extra notifications will negatively impact the insertion rate. - Not all users are interested in these notifications. Signed-off-by: Amit Cohen <amcohen@nvidia.com> Acked-by: Roopa Prabhu <roopa@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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#
ac8f1710 |
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09-Sep-2020 |
Wei Wang <weiwan@google.com> |
tcp: reflect tos value received in SYN to the socket This commit adds a new TCP feature to reflect the tos value received in SYN, and send it out on the SYN-ACK, and eventually set the tos value of the established socket with this reflected tos value. This provides a way to set the traffic class/QoS level for all traffic in the same connection to be the same as the incoming SYN request. It could be useful in data centers to provide equivalent QoS according to the incoming request. This feature is guarded by /proc/sys/net/ipv4/tcp_reflect_tos, and is by default turned off. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f19008e6 |
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10-Aug-2020 |
Jason Baron <jbaron@akamai.com> |
tcp: correct read of TFO keys on big endian systems When TFO keys are read back on big endian systems either via the global sysctl interface or via getsockopt() using TCP_FASTOPEN_KEY, the values don't match what was written. For example, on s390x: # echo "1-2-3-4" > /proc/sys/net/ipv4/tcp_fastopen_key # cat /proc/sys/net/ipv4/tcp_fastopen_key 02000000-01000000-04000000-03000000 Instead of: # cat /proc/sys/net/ipv4/tcp_fastopen_key 00000001-00000002-00000003-00000004 Fix this by converting to the correct endianness on read. This was reported by Colin Ian King when running the 'tcp_fastopen_backup_key' net selftest on s390x, which depends on the read value matching what was written. I've confirmed that the test now passes on big and little endian systems. Signed-off-by: Jason Baron <jbaron@akamai.com> Fixes: 438ac88009bc ("net: fastopen: robustness and endianness fixes for SipHash") Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Eric Dumazet <edumazet@google.com> Reported-and-tested-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a70437cc |
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30-Apr-2020 |
Eric Dumazet <edumazet@google.com> |
tcp: add hrtimer slack to sack compression Add a sysctl to control hrtimer slack, default of 100 usec. This gives the opportunity to reduce system overhead, and help very short RTT flows. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4f80116d |
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27-Apr-2020 |
Roopa Prabhu <roopa@cumulusnetworks.com> |
net: ipv4: add sysctl for nexthop api compatibility mode Current route nexthop API maintains user space compatibility with old route API by default. Dumps and netlink notifications support both new and old API format. In systems which have moved to the new API, this compatibility mode cancels some of the performance benefits provided by the new nexthop API. This patch adds new sysctl nexthop_compat_mode which is on by default but provides the ability to turn off compatibility mode allowing systems to run entirely with the new routing API. Old route API behaviour and support is not modified by this sysctl. Uses a single sysctl to cover both ipv4 and ipv6 following other sysctls. Covers dumps and delete notifications as suggested by David Ahern. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
32927393 |
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24-Apr-2020 |
Christoph Hellwig <hch@lst.de> |
sysctl: pass kernel pointers to ->proc_handler Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
4b01a967 |
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10-Mar-2020 |
Kuniyuki Iwashima <kuniyu@amazon.co.jp> |
tcp: bind(0) remove the SO_REUSEADDR restriction when ephemeral ports are exhausted. Commit aacd9289af8b82f5fb01bcdd53d0e3406d1333c7 ("tcp: bind() use stronger condition for bind_conflict") introduced a restriction to forbid to bind SO_REUSEADDR enabled sockets to the same (addr, port) tuple in order to assign ports dispersedly so that we can connect to the same remote host. The change results in accelerating port depletion so that we fail to bind sockets to the same local port even if we want to connect to the different remote hosts. You can reproduce this issue by following instructions below. 1. # sysctl -w net.ipv4.ip_local_port_range="32768 32768" 2. set SO_REUSEADDR to two sockets. 3. bind two sockets to (localhost, 0) and the latter fails. Therefore, when ephemeral ports are exhausted, bind(0) should fallback to the legacy behaviour to enable the SO_REUSEADDR option and make it possible to connect to different remote (addr, port) tuples. This patch allows us to bind SO_REUSEADDR enabled sockets to the same (addr, port) only when net.ipv4.ip_autobind_reuse is set 1 and all ephemeral ports are exhausted. This also allows connect() and listen() to share ports in the following way and may break some applications. So the ip_autobind_reuse is 0 by default and disables the feature. 1. setsockopt(sk1, SO_REUSEADDR) 2. setsockopt(sk2, SO_REUSEADDR) 3. bind(sk1, saddr, 0) 4. bind(sk2, saddr, 0) 5. connect(sk1, daddr) 6. listen(sk2) If it is set 1, we can fully utilize the 4-tuples, but we should use IP_BIND_ADDRESS_NO_PORT for bind()+connect() as possible. The notable thing is that if all sockets bound to the same port have both SO_REUSEADDR and SO_REUSEPORT enabled, we can bind sockets to an ephemeral port and also do listen(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9cb8e048 |
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19-Feb-2020 |
Christian Brauner <christian.brauner@ubuntu.com> |
net/ipv4/sysctl: show tcp_{allowed, available}_congestion_control in non-initial netns It is currenty possible to switch the TCP congestion control algorithm in non-initial network namespaces: unshare -U --map-root --net --fork --pid --mount-proc echo "reno" > /proc/sys/net/ipv4/tcp_congestion_control works just fine. But currently non-initial network namespaces have no way of kowing which congestion algorithms are available or allowed other than through trial and error by writing the names of the algorithms into the aforementioned file. Since we already allow changing the congestion algorithm in non-initial network namespaces by exposing the tcp_congestion_control file there is no reason to not also expose the tcp_{allowed,available}_congestion_control files to non-initial network namespaces. After this change a container with a separate network namespace will show: root@f1:~# ls -al /proc/sys/net/ipv4/tcp_* | grep congestion -rw-r--r-- 1 root root 0 Feb 19 11:54 /proc/sys/net/ipv4/tcp_allowed_congestion_control -r--r--r-- 1 root root 0 Feb 19 11:54 /proc/sys/net/ipv4/tcp_available_congestion_control -rw-r--r-- 1 root root 0 Feb 19 11:54 /proc/sys/net/ipv4/tcp_congestion_control Link: https://github.com/lxc/lxc/issues/3267 Reported-by: Haw Loeung <haw.loeung@canonical.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
65e6d901 |
|
09-Dec-2019 |
Kevin(Yudong) Yang <yyd@google.com> |
net-tcp: Disable TCP ssthresh metrics cache by default This patch introduces a sysctl knob "net.ipv4.tcp_no_ssthresh_metrics_save" that disables TCP ssthresh metrics cache by default. Other parts of TCP metrics cache, e.g. rtt, cwnd, remain unchanged. As modern networks becoming more and more dynamic, TCP metrics cache today often causes more harm than benefits. For example, the same IP address is often shared by different subscribers behind NAT in residential networks. Even if the IP address is not shared by different users, caching the slow-start threshold of a previous short flow using loss-based congestion control (e.g. cubic) often causes the future longer flows of the same network path to exit slow-start prematurely with abysmal throughput. Caching ssthresh is very risky and can lead to terrible performance. Therefore it makes sense to make disabling ssthresh caching by default and opt-in for specific networks by the administrators. This practice also has worked well for several years of deployment with CUBIC congestion control at Google. Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Kevin(Yudong) Yang <yyd@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9bb59a21 |
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20-Nov-2019 |
Hangbin Liu <liuhangbin@gmail.com> |
tcp: warn if offset reach the maxlen limit when using snprintf snprintf returns the number of chars that would be written, not number of chars that were actually written. As such, 'offs' may get larger than 'tbl.maxlen', causing the 'tbl.maxlen - offs' being < 0, and since the parameter is size_t, it would overflow. Since using scnprintf may hide the limit error, while the buffer is still enough now, let's just add a WARN_ON_ONCE in case it reach the limit in future. v2: Use WARN_ON_ONCE as Jiri and Eric suggested. Suggested-by: Jiri Benc <jbenc@redhat.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ca749bbb |
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18-Nov-2019 |
Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> |
net/ipv4: fix sysctl max for fib_multipath_hash_policy Commit eec4844fae7c ("proc/sysctl: add shared variables for range check") did: - .extra2 = &two, + .extra2 = SYSCTL_ONE, here, which doesn't seem to be intentional, given the changelog. This patch restores it to the previous, as the value of 2 still makes sense (used in fib_multipath_hash()). Fixes: eec4844fae7c ("proc/sysctl: add shared variables for range check") Cc: Matteo Croce <mcroce@redhat.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c04b79b6 |
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07-Aug-2019 |
Josh Hunt <johunt@akamai.com> |
tcp: add new tcp_mtu_probe_floor sysctl The current implementation of TCP MTU probing can considerably underestimate the MTU on lossy connections allowing the MSS to get down to 48. We have found that in almost all of these cases on our networks these paths can handle much larger MTUs meaning the connections are being artificially limited. Even though TCP MTU probing can raise the MSS back up we have seen this not to be the case causing connections to be "stuck" with an MSS of 48 when heavy loss is present. Prior to pushing out this change we could not keep TCP MTU probing enabled b/c of the above reasons. Now with a reasonble floor set we've had it enabled for the past 6 months. The new sysctl will still default to TCP_MIN_SND_MSS (48), but gives administrators the ability to control the floor of MSS probing. Signed-off-by: Josh Hunt <johunt@akamai.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
eec4844f |
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18-Jul-2019 |
Matteo Croce <mcroce@redhat.com> |
proc/sysctl: add shared variables for range check In the sysctl code the proc_dointvec_minmax() function is often used to validate the user supplied value between an allowed range. This function uses the extra1 and extra2 members from struct ctl_table as minimum and maximum allowed value. On sysctl handler declaration, in every source file there are some readonly variables containing just an integer which address is assigned to the extra1 and extra2 members, so the sysctl range is enforced. The special values 0, 1 and INT_MAX are very often used as range boundary, leading duplication of variables like zero=0, one=1, int_max=INT_MAX in different source files: $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l 248 Add a const int array containing the most commonly used values, some macros to refer more easily to the correct array member, and use them instead of creating a local one for every object file. This is the bloat-o-meter output comparing the old and new binary compiled with the default Fedora config: # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164) Data old new delta sysctl_vals - 12 +12 __kstrtab_sysctl_vals - 12 +12 max 14 10 -4 int_max 16 - -16 one 68 - -68 zero 128 28 -100 Total: Before=20583249, After=20583085, chg -0.00% [mcroce@redhat.com: tipc: remove two unused variables] Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com [akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c] [arnd@arndb.de: proc/sysctl: make firmware loader table conditional] Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de [akpm@linux-foundation.org: fix fs/eventpoll.c] Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
438ac880 |
|
19-Jun-2019 |
Ard Biesheuvel <ardb@kernel.org> |
net: fastopen: robustness and endianness fixes for SipHash Some changes to the TCP fastopen code to make it more robust against future changes in the choice of key/cookie size, etc. - Instead of keeping the SipHash key in an untyped u8[] buffer and casting it to the right type upon use, use the correct type directly. This ensures that the key will appear at the correct alignment if we ever change the way these data structures are allocated. (Currently, they are only allocated via kmalloc so they always appear at the correct alignment) - Use DIV_ROUND_UP when sizing the u64[] array to hold the cookie, so it is always of sufficient size, even if TCP_FASTOPEN_COOKIE_MAX is no longer a multiple of 8. - Drop the 'len' parameter from the tcp_fastopen_reset_cipher() function, which is no longer used. - Add endian swabbing when setting the keys and calculating the hash, to ensure that cookie values are the same for a given key and source/destination address pair regardless of the endianness of the server. Note that none of these are functional changes wrt the current state of the code, with the exception of the swabbing, which only affects big endian systems. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2e05fcae |
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15-Jun-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: fix compile error if !CONFIG_SYSCTL tcp_tx_skb_cache_key and tcp_rx_skb_cache_key must be available even if CONFIG_SYSCTL is not set. Fixes: 0b7d7f6b2208 ("tcp: add tcp_tx_skb_cache sysctl") Fixes: ede61ca474a0 ("tcp: add tcp_rx_skb_cache sysctl") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5f3e2bf0 |
|
06-Jun-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: add tcp_min_snd_mss sysctl Some TCP peers announce a very small MSS option in their SYN and/or SYN/ACK messages. This forces the stack to send packets with a very high network/cpu overhead. Linux has enforced a minimal value of 48. Since this value includes the size of TCP options, and that the options can consume up to 40 bytes, this means that each segment can include only 8 bytes of payload. In some cases, it can be useful to increase the minimal value to a saner value. We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility reasons. Note that TCP_MAXSEG socket option enforces a minimal value of (TCP_MIN_MSS). David Miller increased this minimal value in commit c39508d6f118 ("tcp: Make TCP_MAXSEG minimum more correct.") from 64 to 88. We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS. CVE-2019-11479 -- tcp mss hardcoded to 48 Signed-off-by: Eric Dumazet <edumazet@google.com> Suggested-by: Jonathan Looney <jtl@netflix.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Bruce Curtis <brucec@netflix.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0b7d7f6b |
|
14-Jun-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: add tcp_tx_skb_cache sysctl Feng Tang reported a performance regression after introduction of per TCP socket tx/rx caches, for TCP over loopback (netperf) There is high chance the regression is caused by a change on how well the 32 KB per-thread page (current->task_frag) can be recycled, and lack of pcp caches for order-3 pages. I could not reproduce the regression myself, cpus all being spinning on the mm spinlocks for page allocs/freeing, regardless of enabling or disabling the per tcp socket caches. It seems best to disable the feature by default, and let admins enabling it. MM layer either needs to provide scalable order-3 pages allocations, or could attempt a trylock on zone->lock if the caller only attempts to get a high-order page and is able to fallback to order-0 ones in case of pressure. Tests run on a 56 cores host (112 hyper threads) - 35.49% netperf [kernel.vmlinux] [k] queued_spin_lock_slowpath - 35.49% queued_spin_lock_slowpath - 18.18% get_page_from_freelist - __alloc_pages_nodemask - 18.18% alloc_pages_current skb_page_frag_refill sk_page_frag_refill tcp_sendmsg_locked tcp_sendmsg inet_sendmsg sock_sendmsg __sys_sendto __x64_sys_sendto do_syscall_64 entry_SYSCALL_64_after_hwframe __libc_send + 17.31% __free_pages_ok + 31.43% swapper [kernel.vmlinux] [k] intel_idle + 9.12% netperf [kernel.vmlinux] [k] copy_user_enhanced_fast_string + 6.53% netserver [kernel.vmlinux] [k] copy_user_enhanced_fast_string + 0.69% netserver [kernel.vmlinux] [k] queued_spin_lock_slowpath + 0.68% netperf [kernel.vmlinux] [k] skb_release_data + 0.52% netperf [kernel.vmlinux] [k] tcp_sendmsg_locked 0.46% netperf [kernel.vmlinux] [k] _raw_spin_lock_irqsave Fixes: 472c2e07eef0 ("tcp: add one skb cache for tx") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Feng Tang <feng.tang@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ede61ca4 |
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14-Jun-2019 |
Eric Dumazet <edumazet@google.com> |
tcp: add tcp_rx_skb_cache sysctl Instead of relying on rps_needed, it is safer to use a separate static key, since we do not want to enable TCP rx_skb_cache by default. This feature can cause huge increase of memory usage on hosts with millions of sockets. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
363887a2 |
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13-Jun-2019 |
Stephen Suryaputra <ssuryaextr@gmail.com> |
ipv4: Support multipath hashing on inner IP pkts for GRE tunnel Multipath hash policy value of 0 isn't distributing since the outer IP dest and src aren't varied eventhough the inner ones are. Since the flow is on the inner ones in the case of tunneled traffic, hashing on them is desired. This is done mainly for IP over GRE, hence only tested for that. But anything else supported by flow dissection should work. v2: Use skb_flow_dissect_flow_keys() directly so that other tunneling can be supported through flow dissection (per Nikolay Aleksandrov). v3: Remove accidental inclusion of ports in the hash keys and clarify the documentation (Nikolay Alexandrov). Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
aa1236cd |
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28-May-2019 |
Jason Baron <jbaron@akamai.com> |
tcp: add support for optional TFO backup key to net.ipv4.tcp_fastopen_key Add the ability to add a backup TFO key as: # echo "x-x-x-x,x-x-x-x" > /proc/sys/net/ipv4/tcp_fastopen_key The key before the comma acks as the primary TFO key and the key after the comma is the backup TFO key. This change is intended to be backwards compatible since if only one key is set, userspace will simply read back that single key as follows: # echo "x-x-x-x" > /proc/sys/net/ipv4/tcp_fastopen_key # cat /proc/sys/net/ipv4/tcp_fastopen_key x-x-x-x Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9092a76d |
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28-May-2019 |
Jason Baron <jbaron@akamai.com> |
tcp: add backup TFO key infrastructure We would like to be able to rotate TFO keys while minimizing the number of client cookies that are rejected. Currently, we have only one key which can be used to generate and validate cookies, thus if we simply replace this key clients can easily have cookies rejected upon rotation. We propose having the ability to have both a primary key and a backup key. The primary key is used to generate as well as to validate cookies. The backup is only used to validate cookies. Thus, keys can be rotated as: 1) generate new key 2) add new key as the backup key 3) swap the primary and backup key, thus setting the new key as the primary We don't simply set the new key as the primary key and move the old key to the backup slot because the ip may be behind a load balancer and we further allow for the fact that all machines behind the load balancer will not be updated simultaneously. We make use of this infrastructure in subsequent patches. Suggested-by: Igor Lubashev <ilubashe@akamai.com> Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
19fad20d |
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15-Apr-2019 |
ZhangXiaoxu <zhangxiaoxu5@huawei.com> |
ipv4: set the tcp_min_rtt_wlen range from 0 to one day There is a UBSAN report as below: UBSAN: Undefined behaviour in net/ipv4/tcp_input.c:2877:56 signed integer overflow: 2147483647 * 1000 cannot be represented in type 'int' CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.1.0-rc4-00058-g582549e #1 Call Trace: <IRQ> dump_stack+0x8c/0xba ubsan_epilogue+0x11/0x60 handle_overflow+0x12d/0x170 ? ttwu_do_wakeup+0x21/0x320 __ubsan_handle_mul_overflow+0x12/0x20 tcp_ack_update_rtt+0x76c/0x780 tcp_clean_rtx_queue+0x499/0x14d0 tcp_ack+0x69e/0x1240 ? __wake_up_sync_key+0x2c/0x50 ? update_group_capacity+0x50/0x680 tcp_rcv_established+0x4e2/0xe10 tcp_v4_do_rcv+0x22b/0x420 tcp_v4_rcv+0xfe8/0x1190 ip_protocol_deliver_rcu+0x36/0x180 ip_local_deliver+0x15b/0x1a0 ip_rcv+0xac/0xd0 __netif_receive_skb_one_core+0x7f/0xb0 __netif_receive_skb+0x33/0xc0 netif_receive_skb_internal+0x84/0x1c0 napi_gro_receive+0x2a0/0x300 receive_buf+0x3d4/0x2350 ? detach_buf_split+0x159/0x390 virtnet_poll+0x198/0x840 ? reweight_entity+0x243/0x4b0 net_rx_action+0x25c/0x770 __do_softirq+0x19b/0x66d irq_exit+0x1eb/0x230 do_IRQ+0x7a/0x150 common_interrupt+0xf/0xf </IRQ> It can be reproduced by: echo 2147483647 > /proc/sys/net/ipv4/tcp_min_rtt_wlen Fixes: f672258391b42 ("tcp: track min RTT using windowed min-filter") Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9ab948a9 |
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20-Mar-2019 |
David Ahern <dsahern@gmail.com> |
ipv4: Allow amount of dirty memory from fib resizing to be controllable fib_trie implementation calls synchronize_rcu when a certain amount of pages are dirty from freed entries. The number of pages was determined experimentally in 2009 (commit c3059477fce2d). At the current setting, synchronize_rcu is called often -- 51 times in a second in one test with an average of an 8 msec delay adding a fib entry. The total impact is a lot of slow down modifying the fib. This is seen in the output of 'time' - the difference between real time and sys+user. For example, using 720,022 single path routes and 'ip -batch'[1]: $ time ./ip -batch ipv4/routes-1-hops real 0m14.214s user 0m2.513s sys 0m6.783s So roughly 35% of the actual time to install the routes is from the ip command getting scheduled out, most notably due to synchronize_rcu (this is observed using 'perf sched timehist'). This patch makes the amount of dirty memory configurable between 64k where the synchronize_rcu is called often (small, low end systems that are memory sensitive) to 64M where synchronize_rcu is called rarely during a large FIB change (for high end systems with lots of memory). The default is 512kB which corresponds to the current setting of 128 pages with a 4kB page size. As an example, at 16MB the worst interval shows 4 calls to synchronize_rcu in a second blocking for up to 30 msec in a single instance, and a total of almost 100 msec across the 4 calls in the second. The trade off is allowing FIB entries to consume more memory in a given time window but but with much better fib insertion rates (~30% increase in prefixes/sec). With this patch and net.ipv4.fib_sync_mem set to 16MB, the same batch file runs in: $ time ./ip -batch ipv4/routes-1-hops real 0m9.692s user 0m2.491s sys 0m6.769s So the dead time is reduced to about 1/2 second or <5% of the real time. [1] 'ip' modified to not request ACK messages which improves route insertion times by about 20% Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6897445f |
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07-Nov-2018 |
Mike Manning <mmanning@vyatta.att-mail.com> |
net: provide a sysctl raw_l3mdev_accept for raw socket lookup with VRFs Add a sysctl raw_l3mdev_accept to control raw socket lookup in a manner similar to use of tcp_l3mdev_accept for stream and of udp_l3mdev_accept for datagram sockets. Have this default to enabled for reasons of backwards compatibility. This is so as to specify the output device with cmsg and IP_PKTINFO, but using a socket not bound to the corresponding VRF. This allows e.g. older ping implementations to be run with specifying the device but without executing it in the VRF. If the option is disabled, packets received in a VRF context are only handled by a raw socket bound to the VRF, and correspondingly packets in the default VRF are only handled by a socket not bound to any VRF. Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Tested-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d4ce5808 |
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25-Sep-2018 |
Maciej Żenczykowski <maze@google.com> |
net-tcp: /proc/sys/net/ipv4/tcp_probe_interval is a u32 not int (fix documentation and sysctl access to treat it as such) Tested: # zcat /proc/config.gz | egrep ^CONFIG_HZ CONFIG_HZ_1000=y CONFIG_HZ=1000 # echo $[(1<<32)/1000 + 1] | tee /proc/sys/net/ipv4/tcp_probe_interval 4294968 tee: /proc/sys/net/ipv4/tcp_probe_interval: Invalid argument # echo $[(1<<32)/1000] | tee /proc/sys/net/ipv4/tcp_probe_interval 4294967 # echo 0 | tee /proc/sys/net/ipv4/tcp_probe_interval # echo -1 | tee /proc/sys/net/ipv4/tcp_probe_interval -1 tee: /proc/sys/net/ipv4/tcp_probe_interval: Invalid argument Signed-off-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d18c5d19 |
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31-Jul-2018 |
Petr Machata <petrm@mellanox.com> |
net: ipv4: Notify about changes to ip_forward_update_priority Drivers may make offloading decision based on whether ip_forward_update_priority is enabled or not. Therefore distribute netevent notifications to give them a chance to react to a change. Signed-off-by: Petr Machata <petrm@mellanox.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
432e05d3 |
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31-Jul-2018 |
Petr Machata <petrm@mellanox.com> |
net: ipv4: Control SKB reprioritization after forwarding After IPv4 packets are forwarded, the priority of the corresponding SKB is updated according to the TOS field of IPv4 header. This overrides any prioritization done earlier by e.g. an skbedit action or ingress-qos-map defined at a vlan device. Such overriding may not always be desirable. Even if the packet ends up being routed, which implies this is an L3 network node, an administrator may wish to preserve whatever prioritization was done earlier on in the pipeline. Therefore introduce a sysctl that controls this behavior. Keep the default value at 1 to maintain backward-compatible behavior. Signed-off-by: Petr Machata <petrm@mellanox.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
70ba5b6d |
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05-Jul-2018 |
Tyler Hicks <tyhicks@canonical.com> |
ipv4: Return EINVAL when ping_group_range sysctl doesn't map to user ns The low and high values of the net.ipv4.ping_group_range sysctl were being silently forced to the default disabled state when a write to the sysctl contained GIDs that didn't map to the associated user namespace. Confusingly, the sysctl's write operation would return success and then a subsequent read of the sysctl would indicate that the low and high values are the overflowgid. This patch changes the behavior by clearly returning an error when the sysctl write operation receives a GID range that doesn't map to the associated user namespace. In such a situation, the previous value of the sysctl is preserved and that range will be returned in a subsequent read of the sysctl. Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c860e997 |
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27-Jun-2018 |
Yuchung Cheng <ycheng@google.com> |
tcp: fix Fast Open key endianness Fast Open key could be stored in different endian based on the CPU. Previously hosts in different endianness in a server farm using the same key config (sysctl value) would produce different cookies. This patch fixes it by always storing it as little endian to keep same API for LE hosts. Reported-by: Daniele Iamartino <danielei@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
79e9fed4 |
|
03-Jun-2018 |
Maciej Żenczykowski <maze@google.com> |
net-tcp: extend tcp_tw_reuse sysctl to enable loopback only optimization This changes the /proc/sys/net/ipv4/tcp_tw_reuse from a boolean to an integer. It now takes the values 0, 1 and 2, where 0 and 1 behave as before, while 2 enables timewait socket reuse only for sockets that we can prove are loopback connections: ie. bound to 'lo' interface or where one of source or destination IPs is 127.0.0.0/8, ::ffff:127.0.0.0/104 or ::1. This enables quicker reuse of ephemeral ports for loopback connections - where tcp_tw_reuse is 100% safe from a protocol perspective (this assumes no artificially induced packet loss on 'lo'). This also makes estblishing many loopback connections *much* faster (allocating ports out of the first half of the ephemeral port range is significantly faster, then allocating from the second half) Without this change in a 32K ephemeral port space my sample program (it just establishes and closes [::1]:ephemeral -> [::1]:server_port connections in a tight loop) fails after 32765 connections in 24 seconds. With it enabled 50000 connections only take 4.7 seconds. This is particularly problematic for IPv6 where we only have one local address and cannot play tricks with varying source IP from 127.0.0.0/8 pool. Signed-off-by: Maciej Żenczykowski <maze@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Wei Wang <weiwan@google.com> Change-Id: I0377961749979d0301b7b62871a32a4b34b654e1 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9c21d2fc |
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17-May-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: add tcp_comp_sack_nr sysctl This per netns sysctl allows for TCP SACK compression fine-tuning. This limits number of SACK that can be compressed. Using 0 disables SACK compression. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6d82aa24 |
|
17-May-2018 |
Eric Dumazet <edumazet@google.com> |
tcp: add tcp_comp_sack_delay_ns sysctl This per netns sysctl allows for TCP SACK compression fine-tuning. Its default value is 1,000,000, or 1 ms to meet TSO autosizing period. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2f635cee |
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27-Mar-2018 |
Kirill Tkhai <ktkhai@virtuozzo.com> |
net: Drop pernet_operations::async Synchronous pernet_operations are not allowed anymore. All are asynchronous. So, drop the structure member. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1e802951 |
|
13-Mar-2018 |
Tonghao Zhang <xiangxia.m.yue@gmail.com> |
udp: Move the udp sysctl to namespace. This patch moves the udp_rmem_min, udp_wmem_min to namespace and init the udp_l3mdev_accept explicitly. The udp_rmem_min/udp_wmem_min affect udp rx/tx queue, with this patch namespaces can set them differently. Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3192dac6 |
|
02-Mar-2018 |
David Ahern <dsahern@gmail.com> |
net: Rename NETEVENT_MULTIPATH_HASH_UPDATE Rename NETEVENT_MULTIPATH_HASH_UPDATE to NETEVENT_IPV4_MPATH_HASH_UPDATE to denote it relates to a change in the IPv4 hash policy. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
22769a2a |
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12-Feb-2018 |
Kirill Tkhai <ktkhai@virtuozzo.com> |
net: Convert ipv4_sysctl_ops These pernet_operations create and destroy sysctl, which are not touched by anybody else. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Acked-by: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6670e152 |
|
14-Nov-2017 |
Stephen Hemminger <stephen@networkplumber.org> |
tcp: Namespace-ify sysctl_tcp_default_congestion_control Make default TCP default congestion control to a per namespace value. This changes default congestion control to a pointer to congestion ops (rather than implicit as first element of available lsit). The congestion control setting of new namespaces is inherited from the current setting of the root namespace. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
356d1833 |
|
07-Nov-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_rmem and sysctl_tcp_wmem Note that when a new netns is created, it inherits its sysctl_tcp_rmem and sysctl_tcp_wmem from initial netns. This change is needed so that we can refine TCP rcvbuf autotuning, to take RTT into consideration. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3ae6ec08 |
|
02-Nov-2017 |
Ido Schimmel <idosch@mellanox.com> |
ipv4: Send a netevent whenever multipath hash policy is changed Devices performing IPv4 forwarding need to update their multipath hash policy whenever it is changed. Inform these devices by generating a netevent. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Petr Machata <petrm@mellanox.com> Signed-off-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b2441318 |
|
01-Nov-2017 |
Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
c26e91f8 |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_pacing_ca_ratio Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
23a7102a |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_pacing_ss_ratio Also remove an obsolete comment about TCP pacing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4170ba6b |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_invalid_ratelimit Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
790f00e1 |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_autocorking Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
bd239704 |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_min_rtt_wlen Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
26e9596e |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_min_tso_segs Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
b530b681 |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_challenge_ack_limit Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
9184d8bb |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_limit_output_bytes Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ceef9ab6 |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_workaround_signed_windows Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
d06a9904 |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_tso_win_divisor Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
4540c0cf |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_moderate_rcvbuf Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
ec36e416 |
|
27-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_nometrics_save Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
af9b69a7 |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_frto Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
94f0893e |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_adv_win_scale Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
0c12654a |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_app_win Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
6496f6bd |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_dsack Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
c6e21803 |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_max_reordering Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
0bc65a28 |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_fack Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
65c9410c |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_abort_on_overflow Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
625357aa |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_rfc1337 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
3f4c7c6f |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_stdurg Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
e0a1e5b5 |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_retrans_collapse Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
b510f0d2 |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_slow_start_after_idle Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
2c04ac8a |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_thin_linear_timeouts Note that sysctl_tcp_thin_dupack was not used, I deleted it. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
e20223f1 |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_recovery Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
2ae21cf5 |
|
26-Oct-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespace-ify sysctl_tcp_early_retrans Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
1fba70e5 |
|
18-Oct-2017 |
Yuchung Cheng <ycheng@google.com> |
tcp: socket option to set TCP fast open key New socket option TCP_FASTOPEN_KEY to allow different keys per listener. The listener by default uses the global key until the socket option is set. The key is a 16 bytes long binary data. This option has no effect on regular non-listener TCP sockets. Signed-off-by: Yuchung Cheng <ycheng@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
3733be14 |
|
26-Sep-2017 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_fastopen_blackhole_timeout knob Different namespace application might require different time period in second to disable Fastopen on active TCP sockets. Tested: Simulate following similar situation that the server's data gets dropped after 3WHS. C ---- syn-data ---> S C <--- syn/ack ----- S C ---- ack --------> S S (accept & write) C? X <- data ------ S [retry and timeout] And then print netstat of TCPFastOpenBlackhole, the counter increased as expected when the firewall blackhole issue is detected and active TFO is disabled. # cat /proc/net/netstat | awk '{print $91}' TCPFastOpenBlackhole 1 Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
43713848 |
|
26-Sep-2017 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_fastopen_key knob Different namespace application might require different tcp_fastopen_key independently of the host. David Miller pointed out there is a leak without releasing the context of tcp_fastopen_key during netns teardown. So add the release action in exit_batch path. Tested: 1. Container namespace: # cat /proc/sys/net/ipv4/tcp_fastopen_key: 2817fff2-f803cf97-eadfd1f3-78c0992b cookie key in tcp syn packets: Fast Open Cookie Kind: TCP Fast Open Cookie (34) Length: 10 Fast Open Cookie: 1e5dd82a8c492ca9 2. Host: # cat /proc/sys/net/ipv4/tcp_fastopen_key: 107d7c5f-68eb2ac7-02fb06e6-ed341702 cookie key in tcp syn packets: Fast Open Cookie Kind: TCP Fast Open Cookie (34) Length: 10 Fast Open Cookie: e213c02bf0afbc8a Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
dd000598 |
|
26-Sep-2017 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Remove the 'publish' logic in tcp_fastopen_init_key_once The 'publish' logic is not necessary after commit dfea2aa65424 ("tcp: Do not call tcp_fastopen_reset_cipher from interrupt context"), because in tcp_fastopen_cookie_gen,it wouldn't call tcp_fastopen_init_key_once. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
e1cfcbe8 |
|
26-Sep-2017 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_fastopen knob Different namespace application might require enable TCP Fast Open feature independently of the host. This patch series continues making more of the TCP Fast Open related sysctl knobs be per net-namespace. Reported-by: Luca BRUNO <lucab@debian.org> Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
b6690b14 |
|
29-Jul-2017 |
Florian Westphal <fw@strlen.de> |
tcp: remove low_latency sysctl Was only checked by the removed prequeue code. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
734942cc |
|
14-Jun-2017 |
Dave Watson <davejwatson@fb.com> |
tcp: ULP infrastructure Add the infrustructure for attaching Upper Layer Protocols (ULPs) over TCP sockets. Based on a similar infrastructure in tcp_cong. The idea is that any ULP can add its own logic by changing the TCP proto_ops structure to its own methods. Example usage: setsockopt(sock, SOL_TCP, TCP_ULP, "tls", sizeof("tls")); modules will call: tcp_register_ulp(&tcp_tls_ulp_ops); to register/unregister their ulp, with an init function and name. A list of registered ulps will be returned by tcp_get_available_ulp, which is hooked up to /proc. Example: $ cat /proc/sys/net/ipv4/tcp_available_ulp tls There is currently no functionality to remove or chain ULPs, but it should be possible to add these in the future if needed. Signed-off-by: Boris Pismenny <borisp@mellanox.com> Signed-off-by: Dave Watson <davejwatson@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
5d2ed052 |
|
07-Jun-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespaceify sysctl_tcp_timestamps Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
9bb37ef0 |
|
07-Jun-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespaceify sysctl_tcp_window_scaling Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
f9301034 |
|
07-Jun-2017 |
Eric Dumazet <edumazet@google.com> |
tcp: Namespaceify sysctl_tcp_sack Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
cf1ef3f0 |
|
20-Apr-2017 |
Wei Wang <weiwan@google.com> |
net/tcp_fastopen: Disable active side TFO in certain scenarios Middlebox firewall issues can potentially cause server's data being blackholed after a successful 3WHS using TFO. Following are the related reports from Apple: https://www.nanog.org/sites/default/files/Paasch_Network_Support.pdf Slide 31 identifies an issue where the client ACK to the server's data sent during a TFO'd handshake is dropped. C ---> syn-data ---> S C <--- syn/ack ----- S C (accept & write) C <---- data ------- S C ----- ACK -> X S [retry and timeout] https://www.ietf.org/proceedings/94/slides/slides-94-tcpm-13.pdf Slide 5 shows a similar situation that the server's data gets dropped after 3WHS. C ---- syn-data ---> S C <--- syn/ack ----- S C ---- ack --------> S S (accept & write) C? X <- data ------ S [retry and timeout] This is the worst failure b/c the client can not detect such behavior to mitigate the situation (such as disabling TFO). Failing to proceed, the application (e.g., SSL library) may simply timeout and retry with TFO again, and the process repeats indefinitely. The proposed solution is to disable active TFO globally under the following circumstances: 1. client side TFO socket detects out of order FIN 2. client side TFO socket receives out of order RST We disable active side TFO globally for 1hr at first. Then if it happens again, we disable it for 2h, then 4h, 8h, ... And we reset the timeout to 1hr if a client side TFO sockets not opened on loopback has successfully received data segs from server. And we examine this condition during close(). The rational behind it is that when such firewall issue happens, application running on the client should eventually close the socket as it is not able to get the data it is expecting. Or application running on the server should close the socket as it is not able to receive any response from client. In both cases, out of order FIN or RST will get received on the client given that the firewall will not block them as no data are in those frames. And we want to disable active TFO globally as it helps if the middle box is very close to the client and most of the connections are likely to fail. Also, add a debug sysctl: tcp_fastopen_blackhole_detect_timeout_sec: the initial timeout to use when firewall blackhole issue happens. This can be set and read. When setting it to 0, it means to disable the active disable logic. Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
58c4c6a3 |
|
22-Apr-2017 |
David Ahern <dsa@cumulusnetworks.com> |
net: add rcu locking when changing early demux systemd-sysctl is triggering a suspicious RCU usage message when net.ipv4.tcp_early_demux or net.ipv4.udp_early_demux is changed via a sysctl config file: [ 33.896184] =============================== [ 33.899558] [ ERR: suspicious RCU usage. ] [ 33.900624] 4.11.0-rc7+ #104 Not tainted [ 33.901698] ------------------------------- [ 33.903059] /home/dsa/kernel-2.git/net/ipv4/sysctl_net_ipv4.c:305 suspicious rcu_dereference_check() usage! [ 33.905724] other info that might help us debug this: [ 33.907656] rcu_scheduler_active = 2, debug_locks = 0 [ 33.909288] 1 lock held by systemd-sysctl/143: [ 33.910373] #0: (sb_writers#5){.+.+.+}, at: [<ffffffff8123a370>] file_start_write+0x45/0x48 [ 33.912407] stack backtrace: [ 33.914018] CPU: 0 PID: 143 Comm: systemd-sysctl Not tainted 4.11.0-rc7+ #104 [ 33.915631] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 33.917870] Call Trace: [ 33.918431] dump_stack+0x81/0xb6 [ 33.919241] lockdep_rcu_suspicious+0x10f/0x118 [ 33.920263] proc_configure_early_demux+0x65/0x10a [ 33.921391] proc_udp_early_demux+0x3a/0x41 add rcu locking to proc_configure_early_demux. Fixes: dddb64bcb3461 ("net: Add sysctl to toggle early demux for tcp and udp") Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
dddb64bc |
|
23-Mar-2017 |
Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> |
net: Add sysctl to toggle early demux for tcp and udp Certain system process significant unconnected UDP workload. It would be preferrable to disable UDP early demux for those systems and enable it for TCP only. By disabling UDP demux, we see these slight gains on an ARM64 system- 782 -> 788Mbps unconnected single stream UDPv4 633 -> 654Mbps unconnected UDPv4 different sources The performance impact can change based on CPU architecure and cache sizes. There will not much difference seen if entire UDP hash table is in cache. Both sysctls are enabled by default to preserve existing behavior. v1->v2: Change function pointer instead of adding conditional as suggested by Stephen. v2->v3: Read once in callers to avoid issues due to compiler optimizations. Also update commit message with the tests. v3->v4: Store and use read once result instead of querying pointer again incorrectly. v4->v5: Refactor to avoid errors due to compilation with IPV6={m,n} Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Suggested-by: Eric Dumazet <edumazet@google.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Tom Herbert <tom@herbertland.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
bf4e0a3d |
|
16-Mar-2017 |
Nikolay Aleksandrov <nikolay@cumulusnetworks.com> |
net: ipv4: add support for ECMP hash policy choice This patch adds support for ECMP hash policy choice via a new sysctl called fib_multipath_hash_policy and also adds support for L4 hashes. The current values for fib_multipath_hash_policy are: 0 - layer 3 (default) 1 - layer 4 If there's an skb hash already set and it matches the chosen policy then it will be used instead of being calculated (currently only for L4). In L3 mode we always calculate the hash due to the ICMP error special case, the flow dissector's field consistentification should handle the address order thus we can remove the address reversals. If the skb is provided we always use it for the hash calculation, otherwise we fallback to fl4, that is if skb is NULL fl4 has to be set. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
4396e461 |
|
15-Mar-2017 |
Soheil Hassas Yeganeh <soheil@google.com> |
tcp: remove tcp_tw_recycle The tcp_tw_recycle was already broken for connections behind NAT, since the per-destination timestamp is not monotonically increasing for multiple machines behind a single destination address. After the randomization of TCP timestamp offsets in commit 8a5bd45f6616 (tcp: randomize tcp timestamp offsets for each connection), the tcp_tw_recycle is broken for all types of connections for the same reason: the timestamps received from a single machine is not monotonically increasing, anymore. Remove tcp_tw_recycle, since it is not functional. Also, remove the PAWSPassive SNMP counter since it is only used for tcp_tw_recycle, and simplify tcp_v4_route_req and tcp_v6_route_req since the strict argument is only set when tcp_tw_recycle is enabled. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Cc: Lutz Vieweg <lvml@5t9.de> Cc: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
63a6fff3 |
|
26-Jan-2017 |
Robert Shearman <rshearma@brocade.com> |
net: Avoid receiving packets with an l3mdev on unbound UDP sockets Packets arriving in a VRF currently are delivered to UDP sockets that aren't bound to any interface. TCP defaults to not delivering packets arriving in a VRF to unbound sockets. IP route lookup and socket transmit both assume that unbound means using the default table and UDP applications that haven't been changed to be aware of VRFs may not function correctly in this case since they may not be able to handle overlapping IP address ranges, or be able to send packets back to the original sender if required. So add a sysctl, udp_l3mdev_accept, to control this behaviour with it being analgous to the existing tcp_l3mdev_accept, namely to allow a process to have a VRF-global listen socket. Have this default to off as this is the behaviour that users will expect, given that there is no explicit mechanism to set unmodified VRF-unaware application into a default VRF. Signed-off-by: Robert Shearman <rshearma@brocade.com> Acked-by: David Ahern <dsa@cumulusnetworks.com> Tested-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
4548b683 |
|
20-Jan-2017 |
Krister Johansen <kjlx@templeofstupid.com> |
Introduce a sysctl that modifies the value of PROT_SOCK. Add net.ipv4.ip_unprivileged_port_start, which is a per namespace sysctl that denotes the first unprivileged inet port in the namespace. To disable all privileged ports set this to zero. It also checks for overlap with the local port range. The privileged and local range may not overlap. The use case for this change is to allow containerized processes to bind to priviliged ports, but prevent them from ever being allowed to modify their container's network configuration. The latter is accomplished by ensuring that the network namespace is not a child of the user namespace. This modification was needed to allow the container manager to disable a namespace's priviliged port restrictions without exposing control of the network namespace to processes in the user namespace. Signed-off-by: Krister Johansen <kjlx@templeofstupid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
4a7f6009 |
|
12-Jan-2017 |
Yuchung Cheng <ycheng@google.com> |
tcp: remove thin_dupack feature Thin stream DUPACK is to start fast recovery on only one DUPACK provided the connection is a thin stream (i.e., low inflight). But this older feature is now subsumed with RACK. If a connection receives only a single DUPACK, RACK would arm a reordering timer and soon starts fast recovery instead of timeout if no further ACKs are received. The socket option (THIN_DUPACK) is kept as a nop for compatibility. Note that this patch does not change another thin-stream feature which enables linear RTO. Although it might be good to generalize that in the future (i.e., linear RTO for the first say 3 retries). Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
b007f090 |
|
09-Jan-2017 |
Pavel Tikhomirov <ptikhomirov@virtuozzo.com> |
ipv4: make tcp_notsent_lowat sysctl knob behave as true unsigned int > cat /proc/sys/net/ipv4/tcp_notsent_lowat -1 > echo 4294967295 > /proc/sys/net/ipv4/tcp_notsent_lowat -bash: echo: write error: Invalid argument > echo -2147483648 > /proc/sys/net/ipv4/tcp_notsent_lowat > cat /proc/sys/net/ipv4/tcp_notsent_lowat -2147483648 but in documentation we have "tcp_notsent_lowat - UNSIGNED INTEGER" v2: simplify to just proc_douintvec Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
fee83d09 |
|
28-Dec-2016 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_max_syn_backlog knob Different namespace application might require different maximal number of remembered connection requests. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
|
#
1946e672 |
|
28-Dec-2016 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_tw_recycle and tcp_max_tw_buckets knob Different namespace application might require fast recycling TIME-WAIT sockets independently of the host. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
56ab6b93 |
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24-Dec-2016 |
Haishuang Yan <yanhaishuang@cmss.chinamobile.com> |
ipv4: Namespaceify tcp_tw_reuse knob Different namespaces might have different requirements to reuse TIME-WAIT sockets for new connections. This might be required in cases where different namespace applications are in place which require TIME_WAIT socket connections to be reduced independently of the host. Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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396a30cc |
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20-Oct-2016 |
WANG Cong <xiyou.wangcong@gmail.com> |
ipv4: use the right lock for ping_group_range This reverts commit a681574c99be23e4d20b769bf0e543239c364af5 ("ipv4: disable BH in set_ping_group_range()") because we never read ping_group_range in BH context (unlike local_port_range). Then, since we already have a lock for ping_group_range, those using ip_local_ports.lock for ping_group_range are clearly typos. We might consider to share a same lock for both ping_group_range and local_port_range w.r.t. space saving, but that should be for net-next. Fixes: a681574c99be ("ipv4: disable BH in set_ping_group_range()") Fixes: ba6b918ab234 ("ping: move ping_group_range out of CONFIG_SYSCTL") Cc: Eric Dumazet <edumazet@google.com> Cc: Eric Salo <salo@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a681574c |
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20-Oct-2016 |
Eric Dumazet <edumazet@google.com> |
ipv4: disable BH in set_ping_group_range() In commit 4ee3bd4a8c746 ("ipv4: disable BH when changing ip local port range") Cong added BH protection in set_local_port_range() but missed that same fix was needed in set_ping_group_range() Fixes: b8f1a55639e6 ("udp: Add function to make source port for UDP tunnels") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Eric Salo <salo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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049bbf58 |
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20-May-2016 |
Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> |
ipv4: Fix non-initialized TTL when CONFIG_SYSCTL=n Commit fa50d974d104 ("ipv4: Namespaceify ip_default_ttl sysctl knob") moves the default TTL assignment, and as side-effect IPv4 TTL now has a default value only if sysctl support is enabled (CONFIG_SYSCTL=y). The sysctl_ip_default_ttl is fundamental for IP to work properly, as it provides the TTL to be used as default. The defautl TTL may be used in ip_selected_ttl, through the following flow: ip_select_ttl ip4_dst_hoplimit net->ipv4.sysctl_ip_default_ttl This commit fixes the issue by assigning net->ipv4.sysctl_ip_default_ttl in net_init_net, called during ipv4's initialization. Without this commit, a kernel built without sysctl support will send all IP packets with zero TTL (unless a TTL is explicitly set, e.g. with setsockopt). Given a similar issue might appear on the other knobs that were namespaceify, this commit also moves them. Fixes: fa50d974d104 ("ipv4: Namespaceify ip_default_ttl sysctl knob") Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Signed-off-by: David S. Miller <davem@davemloft.net>
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a6db4494 |
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07-Apr-2016 |
David Ahern <dsa@cumulusnetworks.com> |
net: ipv4: Consider failed nexthops in multipath routes Multipath route lookups should consider knowledge about next hops and not select a hop that is known to be failed. Example: [h2] [h3] 15.0.0.5 | | 3| 3| [SP1] [SP2]--+ 1 2 1 2 | | /-------------+ | | \ / | | X | | / \ | | / \---------------\ | 1 2 1 2 12.0.0.2 [TOR1] 3-----------------3 [TOR2] 12.0.0.3 4 4 \ / \ / \ / -------| |-----/ 1 2 [TOR3] 3| | [h1] 12.0.0.1 host h1 with IP 12.0.0.1 has 2 paths to host h3 at 15.0.0.5: root@h1:~# ip ro ls ... 12.0.0.0/24 dev swp1 proto kernel scope link src 12.0.0.1 15.0.0.0/16 nexthop via 12.0.0.2 dev swp1 weight 1 nexthop via 12.0.0.3 dev swp1 weight 1 ... If the link between tor3 and tor1 is down and the link between tor1 and tor2 then tor1 is effectively cut-off from h1. Yet the route lookups in h1 are alternating between the 2 routes: ping 15.0.0.5 gets one and ssh 15.0.0.5 gets the other. Connections that attempt to use the 12.0.0.2 nexthop fail since that neighbor is not reachable: root@h1:~# ip neigh show ... 12.0.0.3 dev swp1 lladdr 00:02:00:00:00:1b REACHABLE 12.0.0.2 dev swp1 FAILED ... The failed path can be avoided by considering known neighbor information when selecting next hops. If the neighbor lookup fails we have no knowledge about the nexthop, so give it a shot. If there is an entry then only select the nexthop if the state is sane. This is similar to what fib_detect_death does. To maintain backward compatibility use of the neighbor information is based on a new sysctl, fib_multipath_use_neigh. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
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e21145a9 |
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14-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: namespacify ip_early_demux sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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287b7f38 |
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14-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespacify ip_dynaddr sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fa50d974 |
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14-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify ip_default_ttl sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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165094af |
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08-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
igmp: Namespacify igmp_qrv sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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87a8a2ae |
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08-Feb-2016 |
Nikolay Borisov <n.borisov@siteground.com> |
igmp: Namespaceify igmp_llm_reports sysctl knob This was initially introduced in df2cf4a78e488d26 ("IGMP: Inhibit reports for local multicast groups") by defining the sysctl in the ipv4_net_table array, however it was never implemented to be namespace aware. Fix this by changing the code accordingly. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
166b6b2d |
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08-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
igmp: Namespaceify igmp_max_msf sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
815c5270 |
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08-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
igmp: Namespaceify igmp_max_memberships sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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4979f2d9 |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp_notsent_lowat sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1e579caa |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp_fin_timeout sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c402d9be |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp_orphan_retries sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c6214a97 |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp_retries2 sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ae5c3f40 |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp_retries1 sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1043e25f |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp reordering sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
12ed8244 |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp syncookies sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7c083ecb |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp synack retries sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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6fa25166 |
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03-Feb-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp syn retries sysctl knob Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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d55f90bf |
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20-Jan-2016 |
Vladimir Davydov <vdavydov.dev@gmail.com> |
net: drop tcp_memcontrol.c tcp_memcontrol.c only contains legacy memory.tcp.kmem.* file definitions and mem_cgroup->tcp_mem init/destroy stuff. This doesn't belong to network subsys. Let's move it to memcontrol.c. This also allows us to reuse generic code for handling legacy memcg files. Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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b840d15d |
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07-Jan-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespecify the tcp_keepalive_intvl sysctl knob This is the final part required to namespaceify the tcp keep alive mechanism. Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9bd6861b |
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07-Jan-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespecify tcp_keepalive_probes sysctl knob This is required to have full tcp keepalive mechanism namespace support. Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
13b287e8 |
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07-Jan-2016 |
Nikolay Borisov <kernel@kyup.com> |
ipv4: Namespaceify tcp_keepalive_time sysctl knob Different net namespaces might have different requirements as to the keepalive time of tcp sockets. This might be required in cases where different firewall rules are in place which require tcp timeout sockets to be increased/decreased independently of the host. Signed-off-by: Nikolay Borisov <kernel@kyup.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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6dd9a14e |
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16-Dec-2015 |
David Ahern <dsa@cumulusnetworks.com> |
net: Allow accepted sockets to be bound to l3mdev domain Allow accepted sockets to derive their sk_bound_dev_if setting from the l3mdev domain in which the packets originated. A sysctl setting is added to control the behavior which is similar to sk_mark and sysctl_tcp_fwmark_accept. This effectively allow a process to have a "VRF-global" listen socket, with child sockets bound to the VRF device in which the packet originated. A similar behavior can be achieved using sk_mark, but a solution using marks is incomplete as it does not handle duplicate addresses in different L3 domains/VRFs. Allowing sockets to inherit the sk_bound_dev_if from l3mdev domain provides a complete solution. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4ee3bd4a |
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03-Nov-2015 |
WANG Cong <xiyou.wangcong@gmail.com> |
ipv4: disable BH when changing ip local port range This fixes the following lockdep warning: [ INFO: inconsistent lock state ] 4.3.0-rc7+ #1197 Not tainted --------------------------------- inconsistent {IN-SOFTIRQ-R} -> {SOFTIRQ-ON-W} usage. sysctl/1019 [HC0[0]:SC0[0]:HE1:SE1] takes: (&(&net->ipv4.ip_local_ports.lock)->seqcount){+.+-..}, at: [<ffffffff81921de7>] ipv4_local_port_range+0xb4/0x12a {IN-SOFTIRQ-R} state was registered at: [<ffffffff810bd682>] __lock_acquire+0x2f6/0xdf0 [<ffffffff810be6d5>] lock_acquire+0x11c/0x1a4 [<ffffffff818e599c>] inet_get_local_port_range+0x4e/0xae [<ffffffff8166e8e3>] udp_flow_src_port.constprop.40+0x23/0x116 [<ffffffff81671cb9>] vxlan_xmit_one+0x219/0xa6a [<ffffffff81672f75>] vxlan_xmit+0xa6b/0xaa5 [<ffffffff817f2deb>] dev_hard_start_xmit+0x2ae/0x465 [<ffffffff817f35ed>] __dev_queue_xmit+0x531/0x633 [<ffffffff817f3702>] dev_queue_xmit_sk+0x13/0x15 [<ffffffff818004a5>] neigh_resolve_output+0x12f/0x14d [<ffffffff81959cfa>] ip6_finish_output2+0x344/0x39f [<ffffffff8195bf58>] ip6_finish_output+0x88/0x8e [<ffffffff8195bfef>] ip6_output+0x91/0xe5 [<ffffffff819792ae>] dst_output_sk+0x47/0x4c [<ffffffff81979392>] NF_HOOK_THRESH.constprop.30+0x38/0x82 [<ffffffff8197981e>] mld_sendpack+0x189/0x266 [<ffffffff8197b28b>] mld_ifc_timer_expire+0x1ef/0x223 [<ffffffff810de581>] call_timer_fn+0xfb/0x28c [<ffffffff810ded1e>] run_timer_softirq+0x1c7/0x1f1 Fixes: b8f1a55639e6 ("udp: Add function to make source port for UDP tunnels") Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4f41b1c5 |
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16-Oct-2015 |
Yuchung Cheng <ycheng@google.com> |
tcp: use RACK to detect losses This patch implements the second half of RACK that uses the the most recent transmit time among all delivered packets to detect losses. tcp_rack_mark_lost() is called upon receiving a dubious ACK. It then checks if an not-yet-sacked packet was sent at least "reo_wnd" prior to the sent time of the most recently delivered. If so the packet is deemed lost. The "reo_wnd" reordering window starts with 1msec for fast loss detection and changes to min-RTT/4 when reordering is observed. We found 1msec accommodates well on tiny degree of reordering (<3 pkts) on faster links. We use min-RTT instead of SRTT because reordering is more of a path property but SRTT can be inflated by self-inflicated congestion. The factor of 4 is borrowed from the delayed early retransmit and seems to work reasonably well. Since RACK is still experimental, it is now used as a supplemental loss detection on top of existing algorithms. It is only effective after the fast recovery starts or after the timeout occurs. The fast recovery is still triggered by FACK and/or dupack threshold instead of RACK. We introduce a new sysctl net.ipv4.tcp_recovery for future experiments of loss recoveries. For now RACK can be disabled by setting it to 0. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f6722583 |
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16-Oct-2015 |
Yuchung Cheng <ycheng@google.com> |
tcp: track min RTT using windowed min-filter Kathleen Nichols' algorithm for tracking the minimum RTT of a data stream over some measurement window. It uses constant space and constant time per update. Yet it almost always delivers the same minimum as an implementation that has to keep all the data in the window. The measurement window is tunable via sysctl.net.ipv4.tcp_min_rtt_wlen with a default value of 5 minutes. The algorithm keeps track of the best, 2nd best & 3rd best min values, maintaining an invariant that the measurement time of the n'th best >= n-1'th best. It also makes sure that the three values are widely separated in the time window since that bounds the worse case error when that data is monotonically increasing over the window. Upon getting a new min, we can forget everything earlier because it has no value - the new min is less than everything else in the window by definition and it's the most recent. So we restart fresh on every new min and overwrites the 2nd & 3rd choices. The same property holds for the 2nd & 3rd best. Therefore we have to maintain two invariants to maximize the information in the samples, one on values (1st.v <= 2nd.v <= 3rd.v) and the other on times (now-win <=1st.t <= 2nd.t <= 3rd.t <= now). These invariants determine the structure of the code The RTT input to the windowed filter is the minimum RTT measured from ACK or SACK, or as the last resort from TCP timestamps. The accessor tcp_min_rtt() returns the minimum RTT seen in the window. ~0U indicates it is not available. The minimum is 1usec even if the true RTT is below that. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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02a6d613 |
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14-Oct-2015 |
Paolo Abeni <pabeni@redhat.com> |
Revert "ipv4/icmp: redirect messages can use the ingress daddr as source" Revert the commit e2ca690b657f ("ipv4/icmp: redirect messages can use the ingress daddr as source"), which tried to introduce a more suitable behaviour for ICMP redirect messages generated by VRRP routers. However RFC 5798 section 8.1.1 states: The IPv4 source address of an ICMP redirect should be the address that the end-host used when making its next-hop routing decision. while said commit used the generating packet destination address, which do not match the above and in most cases leads to no redirect packets to be generated. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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e2ca690b |
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09-Oct-2015 |
Paolo Abeni <pabeni@redhat.com> |
ipv4/icmp: redirect messages can use the ingress daddr as source This patch allows configuring how the source address of ICMP redirect messages is selected; by default the old behaviour is retained, while setting icmp_redirects_use_orig_daddr force the usage of the destination address of the packet that caused the redirect. The new behaviour fits closely the RFC 5798 section 8.1.1, and fix the following scenario: Two machines are set up with VRRP to act as routers out of a subnet, they have IPs x.x.x.1/24 and x.x.x.2/24, with VRRP holding on to x.x.x.254/24. If a host in said subnet needs to get an ICMP redirect from the VRRP router, i.e. to reach a destination behind a different gateway, the source IP in the ICMP redirect is chosen as the primary IP on the interface that the packet arrived at, i.e. x.x.x.1 or x.x.x.2. The host will then ignore said redirect, due to RFC 1122 section 3.2.2.2, and will continue to use the wrong next-op. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
df2cf4a7 |
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27-Aug-2015 |
Philip Downey <pdowney@brocade.com> |
IGMP: Inhibit reports for local multicast groups The range of addresses between 224.0.0.0 and 224.0.0.255 inclusive, is reserved for the use of routing protocols and other low-level topology discovery or maintenance protocols, such as gateway discovery and group membership reporting. Multicast routers should not forward any multicast datagram with destination addresses in this range, regardless of its TTL. Currently, IGMP reports are generated for this reserved range of addresses even though a router will ignore this information since it has no purpose. However, the presence of reserved group addresses in an IGMP membership report uses up network bandwidth and can also obscure addresses of interest when inspecting membership reports using packet inspection or debug messages. Although the RFCs for the various version of IGMP (e.g.RFC 3376 for v3) do not specify that the reserved addresses be excluded from membership reports, it should do no harm in doing so. In particular there should be no adverse effect in any IGMP snooping functionality since 224.0.0.x is specifically excluded as per RFC 4541 (IGMP and MLD Snooping Switches Considerations) section 2.1.2. Data Forwarding Rules: 2) Packets with a destination IP (DIP) address in the 224.0.0.X range which are not IGMP must be forwarded on all ports. IGMP reports for local multicast groups can now be optionally inhibited by means of a system control variable (by setting the value to zero) e.g.: echo 0 > /proc/sys/net/ipv4/igmp_link_local_mcast_reports To retain backwards compatibility the previous behaviour is retained by default on system boot or reverted by setting the value back to non-zero e.g.: echo 1 > /proc/sys/net/ipv4/igmp_link_local_mcast_reports Signed-off-by: Philip Downey <pdowney@brocade.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
43e122b0 |
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21-Aug-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: refine pacing rate determination When TCP pacing was added back in linux-3.12, we chose to apply a fixed ratio of 200 % against current rate, to allow probing for optimal throughput even during slow start phase, where cwnd can be doubled every other gRTT. At Google, we found it was better applying a different ratio while in Congestion Avoidance phase. This ratio was set to 120 %. We've used the normal tcp_in_slow_start() helper for a while, then tuned the condition to select the conservative ratio as soon as cwnd >= ssthresh/2 : - After cwnd reduction, it is safer to ramp up more slowly, as we approach optimal cwnd. - Initial ramp up (ssthresh == INFINITY) still allows doubling cwnd every other RTT. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5d37852b |
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13-Aug-2015 |
Calvin Owens <calvinowens@fb.com> |
Revert "net: limit tcp/udp rmem/wmem to SOCK_{RCV,SND}BUF_MIN" Commit 8133534c760d4083 ("net: limit tcp/udp rmem/wmem to SOCK_{RCV,SND}BUF_MIN") modified four sysctls to enforce that the values written to them are not less than SOCK_MIN_{RCV,SND}BUF. That change causes 4096 to no longer be accepted as a valid value for 'min' in tcp_wmem and udp_wmem_min. 4096 has been the default for both of those sysctls for a long time, and unfortunately seems to be an extremely popular setting. This change breaks a large number of sysctl configurations at Facebook. That commit referred to b1cb59cf2efe7971 ("net: sysctl_net_core: check SNDBUF and RCVBUF for min length"), which choose to use the SOCK_MIN constants as the lower limits to avoid nasty bugs. But AFAICS, a limit of SOCK_MIN_SNDBUF isn't necessary to do that: the BUG_ON cited in the commit message seems to have happened because unix_stream_sendmsg() expects a minimum of a full page (ie SK_MEM_QUANTUM) and the math broke, not because it had less than SOCK_MIN_SNDBUF allocated. This particular issue doesn't seem to affect TCP however: using a setting of "1 1 1" for tcp_{r,w}mem works, although it's obviously suboptimal. SK_MEM_QUANTUM would be a nice minimum, but it's 64K on some archs, so there would still be breakage. Since a value of one doesn't seem to cause any problems, we can drop the minimum 8133534c added to fix this. This reverts commit 8133534c760d4083f79d2cde42c636ccc0b2792e. Fixes: 8133534c760d4083 ("net: limit tcp/udp rmem/wmem to SOCK_MIN...") Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Sorin Dumitru <sorin@returnze.ro> Signed-off-by: Calvin Owens <calvinowens@fb.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8133534c |
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27-May-2015 |
Sorin Dumitru <sorin@returnze.ro> |
net: limit tcp/udp rmem/wmem to SOCK_{RCV,SND}BUF_MIN This is similar to b1cb59cf2efe(net: sysctl_net_core: check SNDBUF and RCVBUF for min length). I don't think too small values can cause crashes in the case of udp and tcp, but I've seen this set to too small values which triggered awful performance. It also makes the setting consistent across all the wmem/rmem sysctls. Signed-off-by: Sorin Dumitru <sdumitru@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ed2dfd90 |
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27-May-2015 |
Eric Dumazet <edumazet@google.com> |
tcp/dccp: warn user for preferred ip_local_port_range After commit 07f4c90062f8f ("tcp/dccp: try to not exhaust ip_local_port_range in connect()") it is advised to have an even number of ports described in /proc/sys/net/ipv4/ip_local_port_range This means start/end values should have a different parity. Let's warn sysadmins of this, so that they can update their settings if they want to. Suggested-by: David S. Miller <davem@davemloft.net> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
d6a4e26a |
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26-May-2015 |
Eric Dumazet <edumazet@google.com> |
tcp: tcp_tso_autosize() minimum is one packet By making sure sk->sk_gso_max_segs minimal value is one, and sysctl_tcp_min_tso_segs minimal value is one as well, tcp_tso_autosize() will return a non zero value. We can then revert 843925f33fcc293d80acf2c5c8a78adf3344d49b ("tcp: Do not apply TSO segment limit to non-TSO packets") and save few cpu cycles in fast path. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
49213555 |
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19-May-2015 |
Daniel Borkmann <daniel@iogearbox.net> |
tcp: add rfc3168, section 6.1.1.1. fallback This work as a follow-up of commit f7b3bec6f516 ("net: allow setting ecn via routing table") and adds RFC3168 section 6.1.1.1. fallback for outgoing ECN connections. In other words, this work adds a retry with a non-ECN setup SYN packet, as suggested from the RFC on the first timeout: [...] A host that receives no reply to an ECN-setup SYN within the normal SYN retransmission timeout interval MAY resend the SYN and any subsequent SYN retransmissions with CWR and ECE cleared. [...] Schematic client-side view when assuming the server is in tcp_ecn=2 mode, that is, Linux default since 2009 via commit 255cac91c3c9 ("tcp: extend ECN sysctl to allow server-side only ECN"): 1) Normal ECN-capable path: SYN ECE CWR -----> <----- SYN ACK ECE ACK -----> 2) Path with broken middlebox, when client has fallback: SYN ECE CWR ----X crappy middlebox drops packet (timeout, rtx) SYN -----> <----- SYN ACK ACK -----> In case we would not have the fallback implemented, the middlebox drop point would basically end up as: SYN ECE CWR ----X crappy middlebox drops packet (timeout, rtx) SYN ECE CWR ----X crappy middlebox drops packet (timeout, rtx) SYN ECE CWR ----X crappy middlebox drops packet (timeout, rtx) In any case, it's rather a smaller percentage of sites where there would occur such additional setup latency: it was found in end of 2014 that ~56% of IPv4 and 65% of IPv6 servers of Alexa 1 million list would negotiate ECN (aka tcp_ecn=2 default), 0.42% of these webservers will fail to connect when trying to negotiate with ECN (tcp_ecn=1) due to timeouts, which the fallback would mitigate with a slight latency trade-off. Recent related paper on this topic: Brian Trammell, Mirja Kühlewind, Damiano Boppart, Iain Learmonth, Gorry Fairhurst, and Richard Scheffenegger: "Enabling Internet-Wide Deployment of Explicit Congestion Notification." Proc. PAM 2015, New York. http://ecn.ethz.ch/ecn-pam15.pdf Thus, when net.ipv4.tcp_ecn=1 is being set, the patch will perform RFC3168, section 6.1.1.1. fallback on timeout. For users explicitly not wanting this which can be in DC use case, we add a net.ipv4.tcp_ecn_fallback knob that allows for disabling the fallback. tp->ecn_flags are not being cleared in tcp_ecn_clear_syn() on output, but rather we let tcp_ecn_rcv_synack() take that over on input path in case a SYN ACK ECE was delayed. Thus a spurious SYN retransmission will not prevent ECN being negotiated eventually in that case. Reference: https://www.ietf.org/proceedings/92/slides/slides-92-iccrg-1.pdf Reference: https://www.ietf.org/proceedings/89/slides/slides-89-tsvarea-1.pdf Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mirja Kühlewind <mirja.kuehlewind@tik.ee.ethz.ch> Signed-off-by: Brian Trammell <trammell@tik.ee.ethz.ch> Cc: Eric Dumazet <edumazet@google.com> Cc: Dave That <dave.taht@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
51456b29 |
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03-Apr-2015 |
Ian Morris <ipm@chirality.org.uk> |
ipv4: coding style: comparison for equality with NULL The ipv4 code uses a mixture of coding styles. In some instances check for NULL pointer is done as x == NULL and sometimes as !x. !x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
05cbc0db |
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05-Mar-2015 |
Fan Du <fan.du@intel.com> |
ipv4: Create probe timer for tcp PMTU as per RFC4821 As per RFC4821 7.3. Selecting Probe Size, a probe timer should be armed once probing has converged. Once this timer expired, probing again to take advantage of any path PMTU change. The recommended probing interval is 10 minutes per RFC1981. Probing interval could be sysctled by sysctl_tcp_probe_interval. Eric Dumazet suggested to implement pseudo timer based on 32bits jiffies tcp_time_stamp instead of using classic timer for such rare event. Signed-off-by: Fan Du <fan.du@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6b58e0a5 |
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05-Mar-2015 |
Fan Du <fan.du@intel.com> |
ipv4: Use binary search to choose tcp PMTU probe_size Current probe_size is chosen by doubling mss_cache, the probing process will end shortly with a sub-optimal mss size, and the link mtu will not be taken full advantage of, in return, this will make user to tweak tcp_base_mss with care. Use binary search to choose probe_size in a fine granularity manner, an optimal mss will be found to boost performance as its maxmium. In addition, introduce a sysctl_tcp_probe_threshold to control when probing will stop in respect to the width of search range. Test env: Docker instance with vxlan encapuslation(82599EB) iperf -c 10.0.0.24 -t 60 before this patch: 1.26 Gbits/sec After this patch: increase 26% 1.59 Gbits/sec Signed-off-by: Fan Du <fan.du@intel.com> Acked-by: John Heffner <johnwheffner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b0f9ca53 |
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09-Feb-2015 |
Fan Du <fan.du@intel.com> |
ipv4: Namespecify TCP PMTU mechanism Packetization Layer Path MTU Discovery works separately beside Path MTU Discovery at IP level, different net namespace has various requirements on which one to chose, e.g., a virutalized container instance would require TCP PMTU to probe an usable effective mtu for underlying tunnel, while the host would employ classical ICMP based PMTU to function. Hence making TCP PMTU mechanism per net namespace to decouple two functionality. Furthermore the probe base MSS should also be configured separately for each namespace. Signed-off-by: Fan Du <fan.du@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
032ee423 |
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06-Feb-2015 |
Neal Cardwell <ncardwell@google.com> |
tcp: helpers to mitigate ACK loops by rate-limiting out-of-window dupacks Helpers for mitigating ACK loops by rate-limiting dupacks sent in response to incoming out-of-window packets. This patch includes: - rate-limiting logic - sysctl to control how often we allow dupacks to out-of-window packets - SNMP counter for cases where we rate-limited our dupack sending The rate-limiting logic in this patch decides to not send dupacks in response to out-of-window segments if (a) they are SYNs or pure ACKs and (b) the remote endpoint is sending them faster than the configured rate limit. We rate-limit our responses rather than blocking them entirely or resetting the connection, because legitimate connections can rely on dupacks in response to some out-of-window segments. For example, zero window probes are typically sent with a sequence number that is below the current window, and ZWPs thus expect to thus elicit a dupack in response. We allow dupacks in response to TCP segments with data, because these may be spurious retransmissions for which the remote endpoint wants to receive DSACKs. This is safe because segments with data can't realistically be part of ACK loops, which by their nature consist of each side sending pure/data-less ACKs to each other. The dupack interval is controlled by a new sysctl knob, tcp_invalid_ratelimit, given in milliseconds, in case an administrator needs to dial this upward in the face of a high-rate DoS attack. The name and units are chosen to be analogous to the existing analogous knob for ICMP, icmp_ratelimit. The default value for tcp_invalid_ratelimit is 500ms, which allows at most one such dupack per 500ms. This is chosen to be 2x faster than the 1-second minimum RTO interval allowed by RFC 6298 (section 2, rule 2.4). We allow the extra 2x factor because network delay variations can cause packets sent at 1 second intervals to be compressed and arrive much closer. Reported-by: Avery Fay <avery@mixpanel.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
dca145ff |
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27-Oct-2014 |
Eric Dumazet <edumazet@google.com> |
tcp: allow for bigger reordering level While testing upcoming Yaogong patch (converting out of order queue into an RB tree), I hit the max reordering level of linux TCP stack. Reordering level was limited to 127 for no good reason, and some network setups [1] can easily reach this limit and get limited throughput. Allow a new max limit of 300, and add a sysctl to allow admins to even allow bigger (or lower) values if needed. [1] Aggregation of links, per packet load balancing, fabrics not doing deep packet inspections, alternative TCP congestion modules... Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yaogong Wang <wygivan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
7bced397 |
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30-Dec-2013 |
Dan Williams <dan.j.williams@intel.com> |
net_dma: simple removal Per commit "77873803363c net_dma: mark broken" net_dma is no longer used and there is no plan to fix it. This is the mechanical removal of bits in CONFIG_NET_DMA ifdef guards. Reverting the remainder of the net_dma induced changes is deferred to subsequent patches. Marked for stable due to Roman's report of a memory leak in dma_pin_iovec_pages(): https://lkml.org/lkml/2014/9/3/177 Cc: Dave Jiang <dave.jiang@intel.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: David Whipple <whipple@securedatainnovations.ch> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Cc: <stable@vger.kernel.org> Reported-by: Roman Gushchin <klamm@yandex-team.ru> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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#
4cdf507d |
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19-Sep-2014 |
Eric Dumazet <edumazet@google.com> |
icmp: add a global rate limitation Current ICMP rate limiting uses inetpeer cache, which is an RBL tree protected by a lock, meaning that hosts can be stuck hard if all cpus want to check ICMP limits. When say a DNS or NTP server process is restarted, inetpeer tree grows quick and machine comes to its knees. iptables can not help because the bottleneck happens before ICMP messages are even cooked and sent. This patch adds a new global limitation, using a token bucket filter, controlled by two new sysctl : icmp_msgs_per_sec - INTEGER Limit maximal number of ICMP packets sent per second from this host. Only messages whose type matches icmp_ratemask are controlled by this limit. Default: 1000 icmp_msgs_burst - INTEGER icmp_msgs_per_sec controls number of ICMP packets sent per second, while icmp_msgs_burst controls the burst size of these packets. Default: 50 Note that if we really want to send millions of ICMP messages per second, we might extend idea and infra added in commit 04ca6973f7c1a ("ip: make IP identifiers less predictable") : add a token bucket in the ip_idents hash and no longer rely on inetpeer. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
49a60158 |
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05-Sep-2014 |
Vincent Bernat <vincent@bernat.im> |
net/ipv4: bind ip_nonlocal_bind to current netns net.ipv4.ip_nonlocal_bind sysctl was global to all network namespaces. This patch allows to set a different value for each network namespace. Signed-off-by: Vincent Bernat <vincent@bernat.im> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a9fe8e29 |
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02-Sep-2014 |
Hannes Frederic Sowa <hannes@stressinduktion.org> |
ipv4: implement igmp_qrv sysctl to tune igmp robustness variable As in IPv6 people might increase the igmp query robustness variable to make sure unsolicited state change reports aren't lost on the network. Add and document this new knob to igmp code. RFCs allow tuning this parameter back to first IGMP RFC, so we also use this setting for all counters, including source specific multicast. Also take over sysctl value when upping the interface and don't reuse the last one seen on the interface. Cc: Flavio Leitner <fbl@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Flavio Leitner <fbl@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
122ff243 |
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12-May-2014 |
WANG Cong <xiyou.wangcong@gmail.com> |
ipv4: make ip_local_reserved_ports per netns ip_local_port_range is already per netns, so should ip_local_reserved_ports be. And since it is none by default we don't actually need it when we don't enable CONFIG_SYSCTL. By the way, rename inet_is_reserved_local_port() to inet_is_local_reserved_port() Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
84f39b08 |
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13-May-2014 |
Lorenzo Colitti <lorenzo@google.com> |
net: support marking accepting TCP sockets When using mark-based routing, sockets returned from accept() may need to be marked differently depending on the incoming connection request. This is the case, for example, if different socket marks identify different networks: a listening socket may want to accept connections from all networks, but each connection should be marked with the network that the request came in on, so that subsequent packets are sent on the correct network. This patch adds a sysctl to mark TCP sockets based on the fwmark of the incoming SYN packet. If enabled, and an unmarked socket receives a SYN, then the SYN packet's fwmark is written to the connection's inet_request_sock, and later written back to the accepted socket when the connection is established. If the socket already has a nonzero mark, then the behaviour is the same as it is today, i.e., the listening socket's fwmark is used. Black-box tested using user-mode linux: - IPv4/IPv6 SYN+ACK, FIN, etc. packets are routed based on the mark of the incoming SYN packet. - The socket returned by accept() is marked with the mark of the incoming SYN packet. - Tested with syncookies=1 and syncookies=2. Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e110861f |
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13-May-2014 |
Lorenzo Colitti <lorenzo@google.com> |
net: add a sysctl to reflect the fwmark on replies Kernel-originated IP packets that have no user socket associated with them (e.g., ICMP errors and echo replies, TCP RSTs, etc.) are emitted with a mark of zero. Add a sysctl to make them have the same mark as the packet they are replying to. This allows an administrator that wishes to do so to use mark-based routing, firewalling, etc. for these replies by marking the original packets inbound. Tested using user-mode linux: - ICMP/ICMPv6 echo replies and errors. - TCP RST packets (IPv4 and IPv6). Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ba6b918a |
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06-May-2014 |
Cong Wang <xiyou.wangcong@gmail.com> |
ping: move ping_group_range out of CONFIG_SYSCTL Similarly, when CONFIG_SYSCTL is not set, ping_group_range should still work, just that no one can change it. Therefore we should move it out of sysctl_net_ipv4.c. And, it should not share the same seqlock with ip_local_port_range. BTW, rename it to ->ping_group_range instead. Cc: David S. Miller <davem@davemloft.net> Cc: Francois Romieu <romieu@fr.zoreil.com> Reported-by: Stefan de Konink <stefan@konink.de> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c9d8f1a6 |
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06-May-2014 |
Cong Wang <xiyou.wangcong@gmail.com> |
ipv4: move local_port_range out of CONFIG_SYSCTL When CONFIG_SYSCTL is not set, ip_local_port_range should still work, just that no one can change it. Therefore we should move it out of sysctl_inet.c. Also, rename it to ->ip_local_ports instead. Cc: David S. Miller <davem@davemloft.net> Cc: Francois Romieu <romieu@fr.zoreil.com> Reported-by: Stefan de Konink <stefan@konink.de> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f87c10a8 |
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09-Jan-2014 |
Hannes Frederic Sowa <hannes@stressinduktion.org> |
ipv4: introduce ip_dst_mtu_maybe_forward and protect forwarding path against pmtu spoofing While forwarding we should not use the protocol path mtu to calculate the mtu for a forwarded packet but instead use the interface mtu. We mark forwarded skbs in ip_forward with IPSKB_FORWARDED, which was introduced for multicast forwarding. But as it does not conflict with our usage in unicast code path it is perfect for reuse. I moved the functions ip_sk_accept_pmtu, ip_sk_use_pmtu and ip_skb_dst_mtu along with the new ip_dst_mtu_maybe_forward to net/ip.h to fix circular dependencies because of IPSKB_FORWARDED. Because someone might have written a software which does probe destinations manually and expects the kernel to honour those path mtus I introduced a new per-namespace "ip_forward_use_pmtu" knob so someone can disable this new behaviour. We also still use mtus which are locked on a route for forwarding. The reason for this change is, that path mtus information can be injected into the kernel via e.g. icmp_err protocol handler without verification of local sockets. As such, this could cause the IPv4 forwarding path to wrongfully emit fragmentation needed notifications or start to fragment packets along a path. Tunnel and ipsec output paths clear IPCB again, thus IPSKB_FORWARDED won't be set and further fragmentation logic will use the path mtu to determine the fragmentation size. They also recheck packet size with help of path mtu discovery and report appropriate errors. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: John Heffner <johnwheffner@gmail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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5797deb6 |
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22-Dec-2013 |
Weilong Chen <chenweilong@huawei.com> |
ipv4: ERROR: code indent should use tabs where possible Signed-off-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
974eda11 |
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13-Dec-2013 |
Hannes Frederic Sowa <hannes@stressinduktion.org> |
inet: make no_pmtu_disc per namespace and kill ipv4_config The other field in ipv4_config, log_martians, was converted to a per-interface setting, so we can just remove the whole structure. Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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f54b3111 |
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05-Dec-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: auto corking With the introduction of TCP Small Queues, TSO auto sizing, and TCP pacing, we can implement Automatic Corking in the kernel, to help applications doing small write()/sendmsg() to TCP sockets. Idea is to change tcp_push() to check if the current skb payload is under skb optimal size (a multiple of MSS bytes) If under 'size_goal', and at least one packet is still in Qdisc or NIC TX queues, set the TCP Small Queue Throttled bit, so that the push will be delayed up to TX completion time. This delay might allow the application to coalesce more bytes in the skb in following write()/sendmsg()/sendfile() system calls. The exact duration of the delay is depending on the dynamics of the system, and might be zero if no packet for this flow is actually held in Qdisc or NIC TX ring. Using FQ/pacing is a way to increase the probability of autocorking being triggered. Add a new sysctl (/proc/sys/net/ipv4/tcp_autocorking) to control this feature and default it to 1 (enabled) Add a new SNMP counter : nstat -a | grep TcpExtTCPAutoCorking This counter is incremented every time we detected skb was under used and its flush was deferred. Tested: Interesting effects when using line buffered commands under ssh. Excellent performance results in term of cpu usage and total throughput. lpq83:~# echo 1 >/proc/sys/net/ipv4/tcp_autocorking lpq83:~# perf stat ./super_netperf 4 -t TCP_STREAM -H lpq84 -- -m 128 9410.39 Performance counter stats for './super_netperf 4 -t TCP_STREAM -H lpq84 -- -m 128': 35209.439626 task-clock # 2.901 CPUs utilized 2,294 context-switches # 0.065 K/sec 101 CPU-migrations # 0.003 K/sec 4,079 page-faults # 0.116 K/sec 97,923,241,298 cycles # 2.781 GHz [83.31%] 51,832,908,236 stalled-cycles-frontend # 52.93% frontend cycles idle [83.30%] 25,697,986,603 stalled-cycles-backend # 26.24% backend cycles idle [66.70%] 102,225,978,536 instructions # 1.04 insns per cycle # 0.51 stalled cycles per insn [83.38%] 18,657,696,819 branches # 529.906 M/sec [83.29%] 91,679,646 branch-misses # 0.49% of all branches [83.40%] 12.136204899 seconds time elapsed lpq83:~# echo 0 >/proc/sys/net/ipv4/tcp_autocorking lpq83:~# perf stat ./super_netperf 4 -t TCP_STREAM -H lpq84 -- -m 128 6624.89 Performance counter stats for './super_netperf 4 -t TCP_STREAM -H lpq84 -- -m 128': 40045.864494 task-clock # 3.301 CPUs utilized 171 context-switches # 0.004 K/sec 53 CPU-migrations # 0.001 K/sec 4,080 page-faults # 0.102 K/sec 111,340,458,645 cycles # 2.780 GHz [83.34%] 61,778,039,277 stalled-cycles-frontend # 55.49% frontend cycles idle [83.31%] 29,295,522,759 stalled-cycles-backend # 26.31% backend cycles idle [66.67%] 108,654,349,355 instructions # 0.98 insns per cycle # 0.57 stalled cycles per insn [83.34%] 19,552,170,748 branches # 488.244 M/sec [83.34%] 157,875,417 branch-misses # 0.81% of all branches [83.34%] 12.130267788 seconds time elapsed Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
9f9843a7 |
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31-Oct-2013 |
Yuchung Cheng <ycheng@google.com> |
tcp: properly handle stretch acks in slow start Slow start now increases cwnd by 1 if an ACK acknowledges some packets, regardless the number of packets. Consequently slow start performance is highly dependent on the degree of the stretch ACKs caused by receiver or network ACK compression mechanisms (e.g., delayed-ACK, GRO, etc). But slow start algorithm is to send twice the amount of packets of packets left so it should process a stretch ACK of degree N as if N ACKs of degree 1, then exits when cwnd exceeds ssthresh. A follow up patch will use the remainder of the N (if greater than 1) to adjust cwnd in the congestion avoidance phase. In addition this patch retires the experimental limited slow start (LSS) feature. LSS has multiple drawbacks but questionable benefit. The fractional cwnd increase in LSS requires a loop in slow start even though it's rarely used. Configuring such an increase step via a global sysctl on different BDPS seems hard. Finally and most importantly the slow start overshoot concern is now better covered by the Hybrid slow start (hystart) enabled by default. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
fd2d5356 |
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19-Oct-2013 |
Eric W. Biederman <ebiederm@xmission.com> |
ipv4: Allow unprivileged users to use per net sysctls Allow unprivileged users to use: /proc/sys/net/ipv4/icmp_echo_ignore_all /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts /proc/sys/net/ipv4/icmp_ignore_bogus_error_response /proc/sys/net/ipv4/icmp_errors_use_inbound_ifaddr /proc/sys/net/ipv4/icmp_ratelimit /proc/sys/net/ipv4/icmp_ratemask /proc/sys/net/ipv4/ping_group_range /proc/sys/net/ipv4/tcp_ecn /proc/sys/net/ipv4/ip_local_ports_range These are occassionally handy and after a quick review I don't see any problems with unprivileged users using them. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0a6fa23d |
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19-Oct-2013 |
Eric W. Biederman <ebiederm@xmission.com> |
ipv4: Use math to point per net sysctls into the appropriate struct net. Simplify maintenance of ipv4_net_table by using math to point the per net sysctls into the appropriate struct net, instead of manually reassinging all of the variables into hard coded table slots. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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a4fe34bf |
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19-Oct-2013 |
Eric W. Biederman <ebiederm@xmission.com> |
tcp_memcontrol: Remove the per netns control. The code that is implemented is per memory cgroup not per netns, and having per netns bits is just confusing. Remove the per netns bits to make it easier to see what is really going on. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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f594d631 |
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19-Oct-2013 |
Eric W. Biederman <ebiederm@xmission.com> |
tcp_memcontrol: Remove setting cgroup settings via sysctl The code is broken and does not constrain sysctl_tcp_mem as tcp_update_limit does. With the result that it allows the cgroup tcp memory limits to be bypassed. The semantics are broken as the settings are not per netns and are in a per netns table, and instead looks at current. Since the code is broken in both design and implementation and does not implement the functionality for which it was written remove it. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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222e83d2 |
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19-Oct-2013 |
Hannes Frederic Sowa <hannes@stressinduktion.org> |
tcp: switch tcp_fastopen key generation to net_get_random_once Changed key initialization of tcp_fastopen cookies to net_get_random_once. If the user sets a custom key net_get_random_once must be called at least once to ensure we don't overwrite the user provided key when the first cookie is generated later on. Cc: Yuchung Cheng <ycheng@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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0bbf87d8 |
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28-Sep-2013 |
Eric W. Biederman <ebiederm@xmission.com> |
net ipv4: Convert ipv4.ip_local_port_range to be per netns v3 - Move sysctl_local_ports from a global variable into struct netns_ipv4. - Modify inet_get_local_port_range to take a struct net, and update all of the callers. - Move the initialization of sysctl_local_ports into sysctl_net_ipv4.c:ipv4_sysctl_init_net from inet_connection_sock.c v2: - Ensure indentation used tabs - Fixed ip.h so it applies cleanly to todays net-next v3: - Compile fixes of strange callers of inet_get_local_port_range. This patch now successfully passes an allmodconfig build. Removed manual inlining of inet_get_local_port_range in ipv4_local_port_range Originally-by: Samya <samya@twitter.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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95bd09eb |
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27-Aug-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: TSO packets automatic sizing After hearing many people over past years complaining against TSO being bursty or even buggy, we are proud to present automatic sizing of TSO packets. One part of the problem is that tcp_tso_should_defer() uses an heuristic relying on upcoming ACKS instead of a timer, but more generally, having big TSO packets makes little sense for low rates, as it tends to create micro bursts on the network, and general consensus is to reduce the buffering amount. This patch introduces a per socket sk_pacing_rate, that approximates the current sending rate, and allows us to size the TSO packets so that we try to send one packet every ms. This field could be set by other transports. Patch has no impact for high speed flows, where having large TSO packets makes sense to reach line rate. For other flows, this helps better packet scheduling and ACK clocking. This patch increases performance of TCP flows in lossy environments. A new sysctl (tcp_min_tso_segs) is added, to specify the minimal size of a TSO packet (default being 2). A follow-up patch will provide a new packet scheduler (FQ), using sk_pacing_rate as an input to perform optional per flow pacing. This explains why we chose to set sk_pacing_rate to twice the current rate, allowing 'slow start' ramp up. sk_pacing_rate = 2 * cwnd * mss / srtt v2: Neal Cardwell reported a suspect deferring of last two segments on initial write of 10 MSS, I had to change tcp_tso_should_defer() to take into account tp->xmit_size_goal_segs Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Van Jacobson <vanj@google.com> Cc: Tom Herbert <therbert@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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c9bee3b7 |
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22-Jul-2013 |
Eric Dumazet <edumazet@google.com> |
tcp: TCP_NOTSENT_LOWAT socket option Idea of this patch is to add optional limitation of number of unsent bytes in TCP sockets, to reduce usage of kernel memory. TCP receiver might announce a big window, and TCP sender autotuning might allow a large amount of bytes in write queue, but this has little performance impact if a large part of this buffering is wasted : Write queue needs to be large only to deal with large BDP, not necessarily to cope with scheduling delays (incoming ACKS make room for the application to queue more bytes) For most workloads, using a value of 128 KB or less is OK to give applications enough time to react to POLLOUT events in time (or being awaken in a blocking sendmsg()) This patch adds two ways to set the limit : 1) Per socket option TCP_NOTSENT_LOWAT 2) A sysctl (/proc/sys/net/ipv4/tcp_notsent_lowat) for sockets not using TCP_NOTSENT_LOWAT socket option (or setting a zero value) Default value being UINT_MAX (0xFFFFFFFF), meaning this has no effect. This changes poll()/select()/epoll() to report POLLOUT only if number of unsent bytes is below tp->nosent_lowat Note this might increase number of sendmsg()/sendfile() calls when using non blocking sockets, and increase number of context switches for blocking sockets. Note this is not related to SO_SNDLOWAT (as SO_SNDLOWAT is defined as : Specify the minimum number of bytes in the buffer until the socket layer will pass the data to the protocol) Tested: netperf sessions, and watching /proc/net/protocols "memory" column for TCP With 200 concurrent netperf -t TCP_STREAM sessions, amount of kernel memory used by TCP buffers shrinks by ~55 % (20567 pages instead of 45458) lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols TCPv6 1880 2 45458 no 208 yes ipv6 y y y y y y y y y y y y y n y y y y y TCP 1696 508 45458 no 208 yes kernel y y y y y y y y y y y y y n y y y y y lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols TCPv6 1880 2 20567 no 208 yes ipv6 y y y y y y y y y y y y y n y y y y y TCP 1696 508 20567 no 208 yes kernel y y y y y y y y y y y y y n y y y y y Using 128KB has no bad effect on the throughput or cpu usage of a single flow, although there is an increase of context switches. A bonus is that we hold socket lock for a shorter amount of time and should improve latencies of ACK processing. lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3 OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf. Local Remote Local Elapsed Throughput Throughput Local Local Remote Remote Local Remote Service Send Socket Recv Socket Send Time Units CPU CPU CPU CPU Service Service Demand Size Size Size (sec) Util Util Util Util Demand Demand Units Final Final % Method % Method 1651584 6291456 16384 20.00 17447.90 10^6bits/s 3.13 S -1.00 U 0.353 -1.000 usec/KB Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3': 412,514 context-switches 200.034645535 seconds time elapsed lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3 OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf. Local Remote Local Elapsed Throughput Throughput Local Local Remote Remote Local Remote Service Send Socket Recv Socket Send Time Units CPU CPU CPU CPU Service Service Demand Size Size Size (sec) Util Util Util Util Demand Demand Units Final Final % Method % Method 1593240 6291456 16384 20.00 17321.16 10^6bits/s 3.35 S -1.00 U 0.381 -1.000 usec/KB Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3': 2,675,818 context-switches 200.029651391 seconds time elapsed Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-By: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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651e9271 |
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19-Jul-2013 |
Michal Tesar <mtesar@redhat.com> |
sysctl net: Keep tcp_syn_retries inside the boundary Limit the min/max value passed to the /proc/sys/net/ipv4/tcp_syn_retries. Signed-off-by: Michal Tesar <mtesar@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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fe2c6338 |
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12-Jun-2013 |
Joe Perches <joe@perches.com> |
net: Convert uses of typedef ctl_table to struct ctl_table Reduce the uses of this unnecessary typedef. Done via perl script: $ git grep --name-only -w ctl_table net | \ xargs perl -p -i -e '\ sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \ s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge' Reflow the modified lines that now exceed 80 columns. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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9b44190d |
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20-Mar-2013 |
Yuchung Cheng <ycheng@google.com> |
tcp: refactor F-RTO The patch series refactor the F-RTO feature (RFC4138/5682). This is to simplify the loss recovery processing. Existing F-RTO was developed during the experimental stage (RFC4138) and has many experimental features. It takes a separate code path from the traditional timeout processing by overloading CA_Disorder instead of using CA_Loss state. This complicates CA_Disorder state handling because it's also used for handling dubious ACKs and undos. While the algorithm in the RFC does not change the congestion control, the implementation intercepts congestion control in various places (e.g., frto_cwnd in tcp_ack()). The new code implements newer F-RTO RFC5682 using CA_Loss processing path. F-RTO becomes a small extension in the timeout processing and interfaces with congestion control and Eifel undo modules. It lets congestion control (module) determines how many to send independently. F-RTO only chooses what to send in order to detect spurious retranmission. If timeout is found spurious it invokes existing Eifel undo algorithms like DSACK or TCP timestamp based detection. The first patch removes all F-RTO code except the sysctl_tcp_frto is left for the new implementation. Since CA_EVENT_FRTO is removed, TCP westwood now computes ssthresh on regular timeout CA_EVENT_LOSS event. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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1a2c6181 |
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17-Mar-2013 |
Christoph Paasch <christoph.paasch@uclouvain.be> |
tcp: Remove TCPCT TCPCT uses option-number 253, reserved for experimental use and should not be used in production environments. Further, TCPCT does not fully implement RFC 6013. As a nice side-effect, removing TCPCT increases TCP's performance for very short flows: Doing an apache-benchmark with -c 100 -n 100000, sending HTTP-requests for files of 1KB size. before this patch: average (among 7 runs) of 20845.5 Requests/Second after: average (among 7 runs) of 21403.6 Requests/Second Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net>
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6ba8a3b1 |
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11-Mar-2013 |
Nandita Dukkipati <nanditad@google.com> |
tcp: Tail loss probe (TLP) This patch series implement the Tail loss probe (TLP) algorithm described in http://tools.ietf.org/html/draft-dukkipati-tcpm-tcp-loss-probe-01. The first patch implements the basic algorithm. TLP's goal is to reduce tail latency of short transactions. It achieves this by converting retransmission timeouts (RTOs) occuring due to tail losses (losses at end of transactions) into fast recovery. TLP transmits one packet in two round-trips when a connection is in Open state and isn't receiving any ACKs. The transmitted packet, aka loss probe, can be either new or a retransmission. When there is tail loss, the ACK from a loss probe triggers FACK/early-retransmit based fast recovery, thus avoiding a costly RTO. In the absence of loss, there is no change in the connection state. PTO stands for probe timeout. It is a timer event indicating that an ACK is overdue and triggers a loss probe packet. The PTO value is set to max(2*SRTT, 10ms) and is adjusted to account for delayed ACK timer when there is only one oustanding packet. TLP Algorithm On transmission of new data in Open state: -> packets_out > 1: schedule PTO in max(2*SRTT, 10ms). -> packets_out == 1: schedule PTO in max(2*RTT, 1.5*RTT + 200ms) -> PTO = min(PTO, RTO) Conditions for scheduling PTO: -> Connection is in Open state. -> Connection is either cwnd limited or no new data to send. -> Number of probes per tail loss episode is limited to one. -> Connection is SACK enabled. When PTO fires: new_segment_exists: -> transmit new segment. -> packets_out++. cwnd remains same. no_new_packet: -> retransmit the last segment. Its ACK triggers FACK or early retransmit based recovery. ACK path: -> rearm RTO at start of ACK processing. -> reschedule PTO if need be. In addition, the patch includes a small variation to the Early Retransmit (ER) algorithm, such that ER and TLP together can in principle recover any N-degree of tail loss through fast recovery. TLP is controlled by the same sysctl as ER, tcp_early_retrans sysctl. tcp_early_retrans==0; disables TLP and ER. ==1; enables RFC5827 ER. ==2; delayed ER. ==3; TLP and delayed ER. [DEFAULT] ==4; TLP only. The TLP patch series have been extensively tested on Google Web servers. It is most effective for short Web trasactions, where it reduced RTOs by 15% and improved HTTP response time (average by 6%, 99th percentile by 10%). The transmitted probes account for <0.5% of the overall transmissions. Signed-off-by: Nandita Dukkipati <nanditad@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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ca2eb567 |
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05-Feb-2013 |
Stephen Hemminger <stephen@networkplumber.org> |
tcp: remove Appropriate Byte Count support TCP Appropriate Byte Count was added by me, but later disabled. There is no point in maintaining it since it is a potential source of bugs and Linux already implements other better window protection heuristics. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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cdda8891 |
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23-Jan-2013 |
bingtian.ly@taobao.com <bingtian.ly@taobao.com> |
net: avoid to hang up on sending due to sysctl configuration overflow. I found if we write a larger than 4GB value to some sysctl variables, the sending syscall will hang up forever, because these variables are 32 bits, such large values make them overflow to 0 or negative. This patch try to fix overflow or prevent from zero value setup of below sysctl variables: net.core.wmem_default net.core.rmem_default net.core.rmem_max net.core.wmem_max net.ipv4.udp_rmem_min net.ipv4.udp_wmem_min net.ipv4.tcp_wmem net.ipv4.tcp_rmem Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Li Yu <raise.sail@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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5d134f1c |
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05-Jan-2013 |
Hannes Frederic Sowa <hannes@stressinduktion.org> |
tcp: make sysctl_tcp_ecn namespace aware As per suggestion from Eric Dumazet this patch makes tcp_ecn sysctl namespace aware. The reason behind this patch is to ease the testing of ecn problems on the internet and allows applications to tune their own use of ecn. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Cc: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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bb717d76 |
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28-Dec-2012 |
stephen hemminger <shemminger@vyatta.com> |
tcp: make proc_tcp_fastopen_key static Detected by sparse. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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464dc801 |
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15-Nov-2012 |
Eric W. Biederman <ebiederm@xmission.com> |
net: Don't export sysctls to unprivileged users In preparation for supporting the creation of network namespaces by unprivileged users, modify all of the per net sysctl exports and refuse to allow them to unprivileged users. This makes it safe for unprivileged users in general to access per net sysctls, and allows sysctls to be exported to unprivileged users on an individual basis as they are deemed safe. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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0e24c4fc |
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11-Oct-2012 |
Alan Cox <alan@linux.intel.com> |
tcp: sysctl interface leaks 16 bytes of kernel memory If the rc_dereference of tcp_fastopen_ctx ever fails then we copy 16 bytes of kernel stack into the proc result. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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10467163 |
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30-Aug-2012 |
Jerry Chu <hkchu@google.com> |
tcp: TCP Fast Open Server - header & support functions This patch adds all the necessary data structure and support functions to implement TFO server side. It also documents a number of flags for the sysctl_tcp_fastopen knob, and adds a few Linux extension MIBs. In addition, it includes the following: 1. a new TCP_FASTOPEN socket option an application must call to supply a max backlog allowed in order to enable TFO on its listener. 2. A number of key data structures: "fastopen_rsk" in tcp_sock - for a big socket to access its request_sock for retransmission and ack processing purpose. It is non-NULL iff 3WHS not completed. "fastopenq" in request_sock_queue - points to a per Fast Open listener data structure "fastopen_queue" to keep track of qlen (# of outstanding Fast Open requests) and max_qlen, among other things. "listener" in tcp_request_sock - to point to the original listener for book-keeping purpose, i.e., to maintain qlen against max_qlen as part of defense against IP spoofing attack. 3. various data structure and functions, many in tcp_fastopen.c, to support server side Fast Open cookie operations, including /proc/sys/net/ipv4/tcp_fastopen_key to allow manual rekeying. Signed-off-by: H.K. Jerry Chu <hkchu@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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7064d16e |
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24-May-2012 |
Eric W. Biederman <ebiederm@xmission.com> |
userns: Use kgids for sysctl_ping_group_range - Store sysctl_ping_group_range as a paire of kgid_t values instead of a pair of gid_t values. - Move the kgid conversion work from ping_init_sock into ipv4_ping_group_range - For invalid cases reset to the default disabled state. With the kgid_t conversion made part of the original value sanitation from userspace understand how the code will react becomes clearer and it becomes possible to set the sysctl ping group range from something other than the initial user namespace. Cc: Vasiliy Kulikov <segoon@openwall.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
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#
c255a458 |
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31-Jul-2012 |
Andrew Morton <akpm@linux-foundation.org> |
memcg: rename config variables Sanity: CONFIG_CGROUP_MEM_RES_CTLR -> CONFIG_MEMCG CONFIG_CGROUP_MEM_RES_CTLR_SWAP -> CONFIG_MEMCG_SWAP CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED -> CONFIG_MEMCG_SWAP_ENABLED CONFIG_CGROUP_MEM_RES_CTLR_KMEM -> CONFIG_MEMCG_KMEM [mhocko@suse.cz: fix missed bits] Cc: Glauber Costa <glommer@parallels.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
0c7462a2 |
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30-Jul-2012 |
Eric Dumazet <edumazet@google.com> |
ipv4: remove rt_cache_rebuild_count After IP route cache removal, rt_cache_rebuild_count is no longer used. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
2100c8d2 |
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19-Jul-2012 |
Yuchung Cheng <ycheng@google.com> |
net-tcp: Fast Open base This patch impelements the common code for both the client and server. 1. TCP Fast Open option processing. Since Fast Open does not have an option number assigned by IANA yet, it shares the experiment option code 254 by implementing draft-ietf-tcpm-experimental-options with a 16 bits magic number 0xF989. This enables global experiments without clashing the scarce(2) experimental options available for TCP. When the draft status becomes standard (maybe), the client should switch to the new option number assigned while the server supports both numbers for transistion. 2. The new sysctl tcp_fastopen 3. A place holder init function Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
282f23c6 |
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17-Jul-2012 |
Eric Dumazet <edumazet@google.com> |
tcp: implement RFC 5961 3.2 Implement the RFC 5691 mitigation against Blind Reset attack using RST bit. Idea is to validate incoming RST sequence, to match RCV.NXT value, instead of previouly accepted window : (RCV.NXT <= SEG.SEQ < RCV.NXT+RCV.WND) If sequence is in window but not an exact match, send a "challenge ACK", so that the other part can resend an RST with the appropriate sequence. Add a new sysctl, tcp_challenge_ack_limit, to limit number of challenge ACK sent per second. Add a new SNMP counter to count number of challenge acks sent. (netstat -s | grep TCPChallengeACK) Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Kiran Kumar Kella <kkiran@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
46d3ceab |
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10-Jul-2012 |
Eric Dumazet <eric.dumazet@gmail.com> |
tcp: TCP Small Queues This introduce TSQ (TCP Small Queues) TSQ goal is to reduce number of TCP packets in xmit queues (qdisc & device queues), to reduce RTT and cwnd bias, part of the bufferbloat problem. sk->sk_wmem_alloc not allowed to grow above a given limit, allowing no more than ~128KB [1] per tcp socket in qdisc/dev layers at a given time. TSO packets are sized/capped to half the limit, so that we have two TSO packets in flight, allowing better bandwidth use. As a side effect, setting the limit to 40000 automatically reduces the standard gso max limit (65536) to 40000/2 : It can help to reduce latencies of high prio packets, having smaller TSO packets. This means we divert sock_wfree() to a tcp_wfree() handler, to queue/send following frames when skb_orphan() [2] is called for the already queued skbs. Results on my dev machines (tg3/ixgbe nics) are really impressive, using standard pfifo_fast, and with or without TSO/GSO. Without reduction of nominal bandwidth, we have reduction of buffering per bulk sender : < 1ms on Gbit (instead of 50ms with TSO) < 8ms on 100Mbit (instead of 132 ms) I no longer have 4 MBytes backlogged in qdisc by a single netperf session, and both side socket autotuning no longer use 4 Mbytes. As skb destructor cannot restart xmit itself ( as qdisc lock might be taken at this point ), we delegate the work to a tasklet. We use one tasklest per cpu for performance reasons. If tasklet finds a socket owned by the user, it sets TSQ_OWNED flag. This flag is tested in a new protocol method called from release_sock(), to eventually send new segments. [1] New /proc/sys/net/ipv4/tcp_limit_output_bytes tunable [2] skb_orphan() is usually called at TX completion time, but some drivers call it in their start_xmit() handler. These drivers should at least use BQL, or else a single TCP session can still fill the whole NIC TX ring, since TSQ will have no effect. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Dave Taht <dave.taht@bufferbloat.net> Cc: Tom Herbert <therbert@google.com> Cc: Matt Mathis <mattmathis@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Nandita Dukkipati <nanditad@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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6648bd7e |
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21-Jun-2012 |
Alexander Duyck <alexander.h.duyck@intel.com> |
ipv4: Add sysctl knob to control early socket demux This change is meant to add a control for disabling early socket demux. The main motivation behind this patch is to provide an option to disable the feature as it adds an additional cost to routing that reduces overall throughput by up to 5%. For example one of my systems went from 12.1Mpps to 11.6 after the early socket demux was added. It looks like the reason for the regression is that we are now having to perform two lookups, first the one for an established socket, and then the one for the routing table. By adding this patch and toggling the value for ip_early_demux to 0 I am able to get back to the 12.1Mpps I was previously seeing. [ Move local variables in ip_rcv_finish() down into the basic block in which they are actually used. -DaveM ] Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
eed530b6 |
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02-May-2012 |
Yuchung Cheng <ycheng@google.com> |
tcp: early retransmit This patch implements RFC 5827 early retransmit (ER) for TCP. It reduces DUPACK threshold (dupthresh) if outstanding packets are less than 4 to recover losses by fast recovery instead of timeout. While the algorithm is simple, small but frequent network reordering makes this feature dangerous: the connection repeatedly enter false recovery and degrade performance. Therefore we implement a mitigation suggested in the appendix of the RFC that delays entering fast recovery by a small interval, i.e., RTT/4. Currently ER is conservative and is disabled for the rest of the connection after the first reordering event. A large scale web server experiment on the performance impact of ER is summarized in section 6 of the paper "Proportional Rate Reduction for TCP”, IMC 2011. http://conferences.sigcomm.org/imc/2011/docs/p155.pdf Note that Linux has a similar feature called THIN_DUPACK. The differences are THIN_DUPACK do not mitigate reorderings and is only used after slow start. Currently ER is disabled if THIN_DUPACK is enabled. I would be happy to merge THIN_DUPACK feature with ER if people think it's a good idea. ER is enabled by sysctl_tcp_early_retrans: 0: Disables ER 1: Reduce dupthresh to packets_out - 1 when outstanding packets < 4. 2: (Default) reduce dupthresh like mode 1. In addition, delay entering fast recovery by RTT/4. Note: mode 2 is implemented in the third part of this patch series. Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a5347fe3 |
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19-Apr-2012 |
Eric W. Biederman <ebiederm@xmission.com> |
net: Delete all remaining instances of ctl_path We don't use struct ctl_path anymore so delete the exported constants. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
ec8f23ce |
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19-Apr-2012 |
Eric W. Biederman <ebiederm@xmission.com> |
net: Convert all sysctl registrations to register_net_sysctl This results in code with less boiler plate that is a bit easier to read. Additionally stops us from using compatibility code in the sysctl core, hastening the day when the compatibility code can be removed. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5dd3df10 |
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19-Apr-2012 |
Eric W. Biederman <ebiederm@xmission.com> |
net: Move all of the network sysctls without a namespace into init_net. This makes it clearer which sysctls are relative to your current network namespace. This makes it a little less error prone by not exposing sysctls for the initial network namespace in other namespaces. This is the same way we handle all of our other network interfaces to userspace and I can't honestly remember why we didn't do this for sysctls right from the start. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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95c96174 |
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14-Apr-2012 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: cleanup unsigned to unsigned int Use of "unsigned int" is preferred to bare "unsigned" in net tree. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c43b874d |
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01-Feb-2012 |
Jason Wang <jasowang@redhat.com> |
tcp: properly initialize tcp memory limits Commit 4acb4190 tries to fix the using uninitialized value introduced by commit 3dc43e3, but it would make the per-socket memory limits too small. This patch fixes this and also remove the redundant codes introduced in 4acb4190. Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Glauber Costa <glommer@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4acb4190 |
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29-Jan-2012 |
Glauber Costa <glommer@parallels.com> |
net/tcp: Fix tcp memory limits initialization when !CONFIG_SYSCTL sysctl_tcp_mem() initialization was moved to sysctl_tcp_ipv4.c in commit 3dc43e3e4d0b52197d3205214fe8f162f9e0c334, since it became a per-ns value. That code, however, will never run when CONFIG_SYSCTL is disabled, leading to bogus values on those fields - causing hung TCP sockets. This patch fixes it by keeping an initialization code in tcp_init(). It will be overwritten by the first net namespace init if CONFIG_SYSCTL is compiled in, and do the right thing if it is compiled out. It is also named properly as tcp_init_mem(), to properly signal its non-sysctl side effect on TCP limits. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Glauber Costa <glommer@parallels.com> Cc: David S. Miller <davem@davemloft.net> Link: http://lkml.kernel.org/r/4F22D05A.8030604@parallels.com [ renamed the function, tidied up the changelog a bit ] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e6560d4d |
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13-Dec-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: ping: remove some sparse errors net/ipv4/sysctl_net_ipv4.c:78:6: warning: symbol 'inet_get_ping_group_range_table' was not declared. Should it be static? net/ipv4/sysctl_net_ipv4.c:119:31: warning: incorrect type in argument 2 (different signedness) net/ipv4/sysctl_net_ipv4.c:119:31: expected int *range net/ipv4/sysctl_net_ipv4.c:119:31: got unsigned int *<noident> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3aaabe23 |
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11-Dec-2011 |
Glauber Costa <glommer@parallels.com> |
tcp buffer limitation: per-cgroup limit This patch uses the "tcp.limit_in_bytes" field of the kmem_cgroup to effectively control the amount of kernel memory pinned by a cgroup. This value is ignored in the root cgroup, and in all others, caps the value specified by the admin in the net namespaces' view of tcp_sysctl_mem. If namespaces are being used, the admin is allowed to set a value bigger than cgroup's maximum, the same way it is allowed to set pretty much unlimited values in a real box. Signed-off-by: Glauber Costa <glommer@parallels.com> Reviewed-by: Hiroyouki Kamezawa <kamezawa.hiroyu@jp.fujitsu.com> CC: David S. Miller <davem@davemloft.net> CC: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3dc43e3e |
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11-Dec-2011 |
Glauber Costa <glommer@parallels.com> |
per-netns ipv4 sysctl_tcp_mem This patch allows each namespace to independently set up its levels for tcp memory pressure thresholds. This patch alone does not buy much: we need to make this values per group of process somehow. This is achieved in the patches that follows in this patchset. Signed-off-by: Glauber Costa <glommer@parallels.com> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> CC: David S. Miller <davem@davemloft.net> CC: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
4b9d9be8 |
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08-Jun-2011 |
Eric Dumazet <eric.dumazet@gmail.com> |
inetpeer: remove unused list Andi Kleen and Tim Chen reported huge contention on inetpeer unused_peers.lock, on memcached workload on a 40 core machine, with disabled route cache. It appears we constantly flip peers refcnt between 0 and 1 values, and we must insert/remove peers from unused_peers.list, holding a contended spinlock. Remove this list completely and perform a garbage collection on-the-fly, at lookup time, using the expired nodes we met during the tree traversal. This removes a lot of code, makes locking more standard, and obsoletes two sysctls (inet_peer_gc_mintime and inet_peer_gc_maxtime). This also removes two pointers in inet_peer structure. There is still a false sharing effect because refcnt is in first cache line of object [were the links and keys used by lookups are located], we might move it at the end of inet_peer structure to let this first cache line mostly read by cpus. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Andi Kleen <andi@firstfloor.org> CC: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f56e03e8 |
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16-May-2011 |
Vasiliy Kulikov <segoon@openwall.com> |
net: ping: fix build failure If CONFIG_PROC_SYSCTL=n the building process fails: ping.c:(.text+0x52af3): undefined reference to `inet_get_ping_group_range_net' Moved inet_get_ping_group_range_net() to ping.c. Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
c319b4d7 |
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13-May-2011 |
Vasiliy Kulikov <segoon@openwall.com> |
net: ipv4: add IPPROTO_ICMP socket kind This patch adds IPPROTO_ICMP socket kind. It makes it possible to send ICMP_ECHO messages and receive the corresponding ICMP_ECHOREPLY messages without any special privileges. In other words, the patch makes it possible to implement setuid-less and CAP_NET_RAW-less /bin/ping. In order not to increase the kernel's attack surface, the new functionality is disabled by default, but is enabled at bootup by supporting Linux distributions, optionally with restriction to a group or a group range (see below). Similar functionality is implemented in Mac OS X: http://www.manpagez.com/man/4/icmp/ A new ping socket is created with socket(PF_INET, SOCK_DGRAM, PROT_ICMP) Message identifiers (octets 4-5 of ICMP header) are interpreted as local ports. Addresses are stored in struct sockaddr_in. No port numbers are reserved for privileged processes, port 0 is reserved for API ("let the kernel pick a free number"). There is no notion of remote ports, remote port numbers provided by the user (e.g. in connect()) are ignored. Data sent and received include ICMP headers. This is deliberate to: 1) Avoid the need to transport headers values like sequence numbers by other means. 2) Make it easier to port existing programs using raw sockets. ICMP headers given to send() are checked and sanitized. The type must be ICMP_ECHO and the code must be zero (future extensions might relax this, see below). The id is set to the number (local port) of the socket, the checksum is always recomputed. ICMP reply packets received from the network are demultiplexed according to their id's, and are returned by recv() without any modifications. IP header information and ICMP errors of those packets may be obtained via ancillary data (IP_RECVTTL, IP_RETOPTS, and IP_RECVERR). ICMP source quenches and redirects are reported as fake errors via the error queue (IP_RECVERR); the next hop address for redirects is saved to ee_info (in network order). socket(2) is restricted to the group range specified in "/proc/sys/net/ipv4/ping_group_range". It is "1 0" by default, meaning that nobody (not even root) may create ping sockets. Setting it to "100 100" would grant permissions to the single group (to either make /sbin/ping g+s and owned by this group or to grant permissions to the "netadmins" group), "0 4294967295" would enable it for the world, "100 4294967295" would enable it for the users, but not daemons. The existing code might be (in the unlikely case anyone needs it) extended rather easily to handle other similar pairs of ICMP messages (Timestamp/Reply, Information Request/Reply, Address Mask Request/Reply etc.). Userspace ping util & patch for it: http://openwall.info/wiki/people/segoon/ping For Openwall GNU/*/Linux it was the last step on the road to the setuid-less distro. A revision of this patch (for RHEL5/OpenVZ kernels) is in use in Owl-current, such as in the 2011/03/12 LiveCD ISOs: http://mirrors.kernel.org/openwall/Owl/current/iso/ Initially this functionality was written by Pavel Kankovsky for Linux 2.4.32, but unfortunately it was never made public. All ping options (-b, -p, -Q, -R, -s, -t, -T, -M, -I), are tested with the patch. PATCH v3: - switched to flowi4. - minor changes to be consistent with raw sockets code. PATCH v2: - changed ping_debug() to pr_debug(). - removed CONFIG_IP_PING. - removed ping_seq_fops.owner field (unused for procfs). - switched to proc_net_fops_create(). - switched to %pK in seq_printf(). PATCH v1: - fixed checksumming bug. - CAP_NET_RAW may not create icmp sockets anymore. RFC v2: - minor cleanups. - introduced sysctl'able group range to restrict socket(2). Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
192910a6 |
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12-Apr-2011 |
Joakim Tjernlund <Joakim.Tjernlund@transmode.se> |
net: Do not wrap sysctl igmp_max_memberships in IP_MULTICAST controlling igmp_max_membership is useful even when IP_MULTICAST is off. Quagga(an OSPF deamon) uses multicast addresses for all interfaces using a single socket and hits igmp_max_membership limit when there are 20 interfaces or more. Always export sysctl igmp_max_memberships in proc, just like igmp_max_msf Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
249fab77 |
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13-Dec-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: add limits to ip_default_ttl ip_default_ttl should be between 1 and 255 Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
323e126f |
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12-Dec-2010 |
David S. Miller <davem@davemloft.net> |
ipv4: Don't pre-seed hoplimit metric. Always go through a new ip4_dst_hoplimit() helper, just like ipv6. This allowed several simplifications: 1) The interim dst_metric_hoplimit() can go as it's no longer userd. 2) The sysctl_ip_default_ttl entry no longer needs to use ipv4_doint_and_flush, since the sysctl is not cached in routing cache metrics any longer. 3) ipv4_doint_and_flush no longer needs to be exported and therefore can be marked static. When ipv4_doint_and_flush_strategy was removed some time ago, the external declaration in ip.h was mistakenly left around so kill that off too. We have to move the sysctl_ip_default_ttl declaration into ipv4's route cache definition header net/route.h, because currently net/ip.h (where the declaration lives now) has a back dependency on net/route.h Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0147fc05 |
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21-Nov-2010 |
Alexey Dobriyan <adobriyan@gmail.com> |
tcp: restrict net.ipv4.tcp_adv_win_scale (#20312) tcp_win_from_space() does the following: if (sysctl_tcp_adv_win_scale <= 0) return space >> (-sysctl_tcp_adv_win_scale); else return space - (space >> sysctl_tcp_adv_win_scale); "space" is int. As per C99 6.5.7 (3) shifting int for 32 or more bits is undefined behaviour. Indeed, if sysctl_tcp_adv_win_scale is exactly 32, space >> 32 equals space and function returns 0. Which means we busyloop in tcp_fixup_rcvbuf(). Restrict net.ipv4.tcp_adv_win_scale to [-31, 31]. Fix https://bugzilla.kernel.org/show_bug.cgi?id=20312 Steps to reproduce: echo 32 >/proc/sys/net/ipv4/tcp_adv_win_scale wget www.kernel.org [softlockup] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8d987e5c |
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09-Nov-2010 |
Eric Dumazet <eric.dumazet@gmail.com> |
net: avoid limits overflow Robin Holt tried to boot a 16TB machine and found some limits were reached : sysctl_tcp_mem[2], sysctl_udp_mem[2] We can switch infrastructure to use long "instead" of "int", now atomic_long_t primitives are available for free. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Reported-by: Robin Holt <holt@sgi.com> Reviewed-by: Robin Holt <holt@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e3826f1e |
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04-May-2010 |
Amerigo Wang <amwang@redhat.com> |
net: reserve ports for applications using fixed port numbers (Dropped the infiniband part, because Tetsuo modified the related code, I will send a separate patch for it once this is accepted.) This patch introduces /proc/sys/net/ipv4/ip_local_reserved_ports which allows users to reserve ports for third-party applications. The reserved ports will not be used by automatic port assignments (e.g. when calling connect() or bind() with port number 0). Explicit port allocation behavior is unchanged. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: WANG Cong <amwang@redhat.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5a0e3ad6 |
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24-Mar-2010 |
Tejun Heo <tj@kernel.org> |
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
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#
7e380175 |
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17-Feb-2010 |
Andreas Petlund <apetlund@simula.no> |
net: TCP thin dupack This patch enables fast retransmissions after one dupACK for TCP if the stream is identified as thin. This will reduce latencies for thin streams that are not able to trigger fast retransmissions due to high packet interarrival time. This mechanism is only active if enabled by iocontrol or syscontrol and the stream is identified as thin. Signed-off-by: Andreas Petlund <apetlund@simula.no> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
36e31b0a |
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17-Feb-2010 |
Andreas Petlund <apetlund@simula.no> |
net: TCP thin linear timeouts This patch will make TCP use only linear timeouts if the stream is thin. This will help to avoid the very high latencies that thin stream suffer because of exponential backoff. This mechanism is only active if enabled by iocontrol or syscontrol and the stream is identified as thin. A maximum of 6 linear timeouts is tried before exponential backoff is resumed. Signed-off-by: Andreas Petlund <apetlund@simula.no> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
519855c5 |
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02-Dec-2009 |
William Allen Simpson <william.allen.simpson@gmail.com> |
TCPCT part 1c: sysctl_tcp_cookie_size, socket option TCP_COOKIE_TRANSACTIONS Define sysctl (tcp_cookie_size) to turn on and off the cookie option default globally, instead of a compiled configuration option. Define per socket option (TCP_COOKIE_TRANSACTIONS) for setting constant data values, retrieving variable cookie values, and other facilities. Move inline tcp_clear_options() unchanged from net/tcp.h to linux/tcp.h, near its corresponding struct tcp_options_received (prior to changes). This is a straightforward re-implementation of an earlier (year-old) patch that no longer applies cleanly, with permission of the original author (Adam Langley): http://thread.gmane.org/gmane.linux.network/102586 These functions will also be used in subsequent patches that implement additional features. Requires: net: TCP_MSS_DEFAULT, TCP_MSS_DESIRED Signed-off-by: William.Allen.Simpson@gmail.com Signed-off-by: David S. Miller <davem@davemloft.net>
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#
09ad9bc7 |
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25-Nov-2009 |
Octavian Purdila <opurdila@ixiacom.com> |
net: use net_eq to compare nets Generated with the following semantic patch @@ struct net *n1; struct net *n2; @@ - n1 == n2 + net_eq(n1, n2) @@ struct net *n1; struct net *n2; @@ - n1 != n2 + !net_eq(n1, n2) applied over {include,net,drivers/net}. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f8572d8f |
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05-Nov-2009 |
Eric W. Biederman <ebiederm@xmission.com> |
sysctl net: Remove unused binary sysctl code Now that sys_sysctl is a compatiblity wrapper around /proc/sys all sysctl strategy routines, and all ctl_name and strategy entries in the sysctl tables are unused, and can be revmoed. In addition neigh_sysctl_register has been modified to no longer take a strategy argument and it's callers have been modified not to pass one. Cc: "David Miller" <davem@davemloft.net> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: netdev@vger.kernel.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
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#
8d65af78 |
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23-Sep-2009 |
Alexey Dobriyan <adobriyan@gmail.com> |
sysctl: remove "struct file *" argument of ->proc_handler It's unused. It isn't needed -- read or write flag is already passed and sysctl shouldn't care about the rest. It _was_ used in two places at arch/frv for some reason. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
6d9f239a |
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03-Nov-2008 |
Alexey Dobriyan <adobriyan@gmail.com> |
net: '&' redux I want to compile out proc_* and sysctl_* handlers totally and stub them to NULL depending on config options, however usage of & will prevent this, since taking adress of NULL pointer will break compilation. So, drop & in front of every ->proc_handler and every ->strategy handler, it was never needed in fact. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1080d709 |
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27-Oct-2008 |
Neil Horman <nhorman@tuxdriver.com> |
net: implement emergency route cache rebulds when gc_elasticity is exceeded This is a patch to provide on demand route cache rebuilding. Currently, our route cache is rebulid periodically regardless of need. This introduced unneeded periodic latency. This patch offers a better approach. Using code provided by Eric Dumazet, we compute the standard deviation of the average hash bucket chain length while running rt_check_expire. Should any given chain length grow to larger that average plus 4 standard deviations, we trigger an emergency hash table rebuild for that net namespace. This allows for the common case in which chains are well behaved and do not grow unevenly to not incur any latency at all, while those systems (which may be being maliciously attacked), only rebuild when the attack is detected. This patch take 2 other factors into account: 1) chains with multiple entries that differ by attributes that do not affect the hash value are only counted once, so as not to unduly bias system to rebuilding if features like QOS are heavily used 2) if rebuilding crosses a certain threshold (which is adjustable via the added sysctl in this patch), route caching is disabled entirely for that net namespace, since constant rebuilding is less efficient that no caching at all Tested successfully by me. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
f221e726 |
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15-Oct-2008 |
Alexey Dobriyan <adobriyan@gmail.com> |
sysctl: simplify ->strategy name and nlen parameters passed to ->strategy hook are unused, remove them. In general ->strategy hook should know what it's doing, and don't do something tricky for which, say, pointer to original userspace array may be needed (name). Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> [ networking bits ] Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Howells <dhowells@redhat.com> Cc: Matt Mackall <mpm@selenic.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
3c689b73 |
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08-Oct-2008 |
Eric Dumazet <dada1@cosmosbay.com> |
inet: cleanup of local_port_range I noticed sysctl_local_port_range[] and its associated seqlock sysctl_local_port_range_lock were on separate cache lines. Moreover, sysctl_local_port_range[] was close to unrelated variables, highly modified, leading to cache misses. Moving these two variables in a structure can help data locality and moving this structure to read_mostly section helps sharing of this data among cpus. Cleanup of extern declarations (moved in include file where they belong), and use of inet_get_local_port_range() accessor instead of direct access to ports values. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
adf044c8 |
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03-Aug-2008 |
Sven Wegener <sven.wegener@stealer.net> |
net: Add missing extra2 parameter for ip_default_ttl sysctl Commit 76e6ebfb40a2455c18234dcb0f9df37533215461 ("netns: add namespace parameter to rt_cache_flush") acceses the extra2 parameter of the ip_default_ttl ctl_table, but it is never set to a meaningful value. When e84f84f276473dcc673f360e8ff3203148bdf0e2 ("netns: place rt_genid into struct net") is applied, we'll oops in rt_cache_invalidate(). Set extra2 to init_net, to avoid that. Reported-by: Marcin Slusarz <marcin.slusarz@gmail.com> Signed-off-by: Sven Wegener <sven.wegener@stealer.net> Tested-by: Marcin Slusarz <marcin.slusarz@gmail.com> Acked-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
eeb61f71 |
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27-Jul-2008 |
Al Viro <viro@ZenIV.linux.org.uk> |
missing bits of net-namespace / sysctl Piss-poor sysctl registration API strikes again, film at 11... What we really need is _pathname_ required to be present in already registered table, so that kernel could warn about bad order. That's the next target for sysctl stuff (and generally saner and more explicit order of initialization of ipv[46] internals wouldn't hurt either). For the time being, here are full fixups required by ..._rotable() stuff; we make per-net sysctl sets descendents of "ro" one and make sure that sufficient skeleton is there before we start registering per-net sysctls. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
6f9f489a |
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27-Jul-2008 |
Al Viro <viro@zeniv.linux.org.uk> |
net: missing bits of net-namespace / sysctl Piss-poor sysctl registration API strikes again, film at 11... What we really need is _pathname_ required to be present in already registered table, so that kernel could warn about bad order. That's the next target for sysctl stuff (and generally saner and more explicit order of initialization of ipv[46] internals wouldn't hurt either). For the time being, here are full fixups required by ..._rotable() stuff; we make per-net sysctl sets descendents of "ro" one and make sure that sufficient skeleton is there before we start registering per-net sysctls. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bd7b1533 |
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15-Jul-2008 |
Al Viro <viro@zeniv.linux.org.uk> |
[PATCH] sysctl: make sure that /proc/sys/net/ipv4 appears before per-ns ones Massage ipv4 initialization - make sure that net.ipv4 appears as non-per-net-namespace before it shows up in per-net-namespace sysctls. That's the only change outside of sysctl.c needed to get sane ordering rules and data structures for sysctls (esp. for procfs side of that mess). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
6dbf4bca |
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01-Jul-2008 |
Stephen Hemminger <shemminger@vyatta.com> |
icmp: fix units for ratelimit Convert the sysctl values for icmp ratelimit to use milliseconds instead of jiffies which is based on kernel configured HZ. Internal kernel jiffies are not a proper unit for any userspace API. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
0b040829 |
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10-Jun-2008 |
Adrian Bunk <bunk@kernel.org> |
net: remove CVS keywords This patch removes CVS keywords that weren't updated for a long time from comments. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
68528f09 |
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26-Mar-2008 |
Pavel Emelyanov <xemul@openvz.org> |
[NETNS][ICMP]: Make ctl tables for ICMP sysctls per-net. Add some flesh to ipv4_sysctl_init_net and ipv4_sysctl_exit_net, i.e. copy the table, alter .data pointers and register it per-net. Other ipv4_table's sysctls are now global, but this is going to change once sysctl permissions patches migrate from -mm tree to mainline in 2.6.26 merge window :) Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a24022e1 |
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26-Mar-2008 |
Pavel Emelyanov <xemul@openvz.org> |
[NETNS][ICMP]: Move ICMP sysctls on struct net. Initialization is moved to icmp_sk_init, all the places, that refer to them use init_net for now. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1577519d |
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26-Mar-2008 |
Pavel Emelyanov <xemul@openvz.org> |
[NETNS][ICMP]: Register pernet subsys to make ICMP sysctls per-net. This includes adding pernet_operations, empty init and exit hooks and a bit of changes in sysctl_ipv4_init just not to have this part in next patches. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
16ca3f91 |
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31-Jan-2008 |
Shan Wei <shanwei@cn.fujitsu.com> |
[TCP]: Fix a bug in strategy_allowed_congestion_control In strategy_allowed_congestion_control of the 2.6.24 kernel, when sysctl_string return 1 on success,it should call tcp_set_allowed_congestion_control to set the allowed congestion control.But, it don't. the sysctl_string return 1 on success, otherwise return negative, never return 0.The patch fix the problem. Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
8d8354d2 |
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22-Jan-2008 |
Pavel Emelyanov <xemul@openvz.org> |
[NETNS][FRAGS]: Move ctl tables around. This is a preparation for sysctl netns-ization. Move the ctl tables to the files, where the tuning variables reside. Plus make the helpers to register the tables. This will simplify the later patches and will keep similar things closer to each other. ipv4, ipv6 and conntrack_reasm are patched differently, but the result is all the tables are in appropriate files. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3d7cc2ba |
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09-Jan-2008 |
Pavel Emelyanov <xemul@openvz.org> |
[NETFILTER]: Switch to using ctl_paths in nf_queue and conntrack modules This includes the most simple cases for netfilter. The first part is tne queue modules for ipv4 and ipv6, on which the net/ipv4/ and net/ipv6/ paths are reused from the appropriate ipv4 and ipv6 code. The conntrack module is also patched, but this hunk is very small and simple. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
95766fff |
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31-Dec-2007 |
Hideo Aoki <haoki@redhat.com> |
[UDP]: Add memory accounting. Signed-off-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Hideo Aoki <haoki@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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68dd299b |
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05-Dec-2007 |
Pavel Emelyanov <xemul@openvz.org> |
[INET]: Merge sys.net.ipv4.ip_forward and sys.net.ipv4.conf.all.forwarding AFAIS these two entries should do the same thing - change the forwarding state on ipv4_devconf and on all the devices. I propose to merge the handlers together using ctl paths. The inet_forward_change() is static after this and I move it higher to be closer to other "propagation" helpers and to avoid diff making patches based on { and } matching :) i.e. - make them easier to read. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3e37c3f9 |
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05-Dec-2007 |
Pavel Emelyanov <xemul@openvz.org> |
[IPV4]: Use ctl paths to register net/ipv4/ table This is the same as I did for the net/core/ table in the second patch in his series: use the paths and isolate the whole table in the .c file. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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9ba63979 |
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05-Dec-2007 |
Pavel Emelyanov <xemul@openvz.org> |
[IPV4]: Cleanup the sysctl_net_ipv4.c file This includes several cleanups: * tune Makefile to compile out this file when SYSCTL=n. Now it looks like net/core/sysctl_net_core.c one; * move the ipv4_config to af_inet.c to exist all the time; * remove additional sysctl_ip_nonlocal_bind declaration (it is already declared in net/ip.h); * remove no nonger needed ifdefs from this file. This is a preparation for using ctl paths for net/ipv4/ sysctl table. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
5487796f |
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20-Nov-2007 |
Sam Jansen <sjansen@google.com> |
[TCP]: Problem bug with sysctl_tcp_congestion_control function From: "Sam Jansen" <sjansen@google.com> sysctl_tcp_congestion_control seems to have a bug that prevents it from actually calling the tcp_set_default_congestion_control function. This is not so apparent because it does not return an error and generally the /proc interface is used to configure the default TCP congestion control algorithm. This is present in 2.6.18 onwards and probably earlier, though I have not inspected 2.6.15--2.6.17. sysctl_tcp_congestion_control calls sysctl_string and expects a successful return code of 0. In such a case it actually sets the congestion control algorithm with tcp_set_default_congestion_control. Otherwise, it returns the value returned by sysctl_string. This was correct in 2.6.14, as sysctl_string returned 0 on success. However, sysctl_string was updated to return 1 on success around about 2.6.15 and sysctl_tcp_congestion_control was not updated. Even though sysctl_tcp_congestion_control returns 1, do_sysctl_strategy converts this return code to '0', so the caller never notices the error. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
a25de534 |
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18-Oct-2007 |
Anton Arapov <aarapov@redhat.com> |
[INET]: Justification for local port range robustness. There is a justifying patch for Stephen's patches. Stephen's patches disallows using a port range of one single port and brakes the meaning of the 'remaining' variable, in some places it has different meaning. My patch gives back the sense of 'remaining' variable. It should mean how many ports are remaining and nothing else. Also my patch allows using a single port. I sure we must be able to use mentioned port range, this does not restricted by documentation and does not brake current behavior. usefull links: Patches posted by Stephen Hemminger http://marc.info/?l=linux-netdev&m=119206106218187&w=2 http://marc.info/?l=linux-netdev&m=119206109918235&w=2 Andrew Morton's comment http://marc.info/?l=linux-kernel&m=119248225007737&w=2 1. Allows using a port range of one single port. 2. Gives back sense of 'remaining' variable. Signed-off-by: Anton Arapov <aarapov@redhat.com> Acked-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
49641b58 |
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18-Oct-2007 |
Eric W. Biederman <ebiederm@xmission.com> |
sysctl: ipv4 remove binary sysctl paths where they are broken Currently tcp_available_congestion_control does not even attempt being read from sys_sysctl, and ipfrag_max_dist while it works allows setting of invalid values using sys_sysctl. So just kill the binary sys_sysctl support for these sysctls. If the support is not important enough to test and get right it probably isn't important enough to keep. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Alexey Dobriyan <adobriyan@sw.ru> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
04128f23 |
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15-Oct-2007 |
Pavel Emelyanov <xemul@openvz.org> |
[INET]: Collect common frag sysctl variables together Some sysctl variables are used to tune the frag queues management and it will be useful to work with them in a common way in the future, so move them into one structure, moreover they are the same for all the frag management codes. I don't place them in the existing inet_frags object, introduced in the previous patch for two reasons: 1. to keep them in the __read_mostly section; 2. not to export the whole inet_frags objects outside. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
227b60f5 |
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10-Oct-2007 |
Stephen Hemminger <shemminger@linux-foundation.org> |
[INET]: local port range robustness Expansion of original idea from Denis V. Lunev <den@openvz.org> Add robustness and locking to the local_port_range sysctl. 1. Enforce that low < high when setting. 2. Use seqlock to ensure atomic update. The locking might seem like overkill, but there are cases where sysadmin might want to change value in the middle of a DoS attack. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
42f811b8 |
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05-Jun-2007 |
Herbert Xu <herbert@gondor.apana.org.au> |
[IPV4]: Convert IPv4 devconf to an array This patch converts the ipv4_devconf config members (everything except sysctl) to an array. This allows easier manipulation which will be needed later on to provide better management of default config values. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
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3cfe3baa |
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27-Feb-2007 |
Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> |
[TCP]: Add two new spurious RTO responses to FRTO New sysctl tcp_frto_response is added to select amongst these responses: - Rate halving based; reuses CA_CWR state (default) - Very conservative; used to be the only one available (=1) - Undo cwr; undoes ssthresh and cwnd reductions (=2) The response with rate halving requires a new parameter to tcp_enter_cwr because FRTO has already reduced ssthresh and doing a second reduction there has to be prevented. In addition, to keep things nice on 80 cols screen, a local variable was added. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
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886236c1 |
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25-Mar-2007 |
John Heffner <jheffner@psc.edu> |
[TCP]: Add RFC3742 Limited Slow-Start, controlled by variable sysctl_tcp_max_ssthresh. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
e905a9ed |
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09-Feb-2007 |
YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> |
[NET] IPV4: Fix whitespace errors. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
1f29bcd7 |
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10-Dec-2006 |
Alexey Dobriyan <adobriyan@gmail.com> |
[PATCH] sysctl: remove unused "context" param Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andi Kleen <ak@suse.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: David Howells <dhowells@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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ce7bc3bf |
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09-Nov-2006 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: Restrict congestion control choices. Allow normal users to only choose among a restricted set of congestion control choices. The default is reno and what ever has been configured as default. But the policy can be changed by administrator at any time. For example, to allow any choice: cp /proc/sys/net/ipv4/tcp_available_congestion_control \ /proc/sys/net/ipv4/tcp_allowed_congestion_control Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3ff825b2 |
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09-Nov-2006 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: Add tcp_available_congestion_control sysctl. Create /proc/sys/net/ipv4/tcp_available_congestion_control that reflects currently available TCP choices. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
b1736a71 |
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31-Oct-2006 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: Set default congestion control when no sysctl. The setting of the default congestion control was buried in the sysctl code so it would not be done properly if SYSCTL was not enabled. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
3d2573f7 |
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24-Sep-2006 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: default congestion control menu Change how default TCP congestion control is chosen. Don't just use last installed module, instead allow selection during configuration, and make sure and use the default regardless of load order. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
446fda4f |
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03-Aug-2006 |
Paul Moore <paul.moore@hp.com> |
[NetLabel]: CIPSOv4 engine Add support for the Commercial IP Security Option (CIPSO) to the IPv4 network stack. CIPSO has become a de-facto standard for trusted/labeled networking amongst existing Trusted Operating Systems such as Trusted Solaris, HP-UX CMW, etc. This implementation is designed to be used with the NetLabel subsystem to provide explicit packet labeling to LSM developers. The CIPSO/IPv4 packet labeling works by the LSM calling a NetLabel API function which attaches a CIPSO label (IPv4 option) to a given socket; this in turn attaches the CIPSO label to every packet leaving the socket without any extra processing on the outbound side. On the inbound side the individual packet's sk_buff is examined through a call to a NetLabel API function to determine if a CIPSO/IPv4 label is present and if so the security attributes of the CIPSO label are returned to the caller of the NetLabel API function. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
6ab3d562 |
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30-Jun-2006 |
Jörn Engel <joern@wohnheim.fh-wedel.de> |
Remove obsolete #include <linux/config.h> Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
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#
35089bb2 |
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13-Jun-2006 |
David S. Miller <davem@sunset.davemloft.net> |
[TCP]: Add tcp_slow_start_after_idle sysctl. A lot of people have asked for a way to disable tcp_cwnd_restart(), and it seems reasonable to add a sysctl to do that. Signed-off-by: David S. Miller <davem@davemloft.net>
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#
bdeb04c6 |
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11-Jun-2006 |
Stephen Hemminger <shemminger@osdl.org> |
[NET]: net.ipv4.ip_autoconfig sysctl removal The sysctl net.ipv4.ip_autoconfig is a legacy value that is not used. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
95937825 |
|
23-May-2006 |
Chris Leech <christopher.leech@intel.com> |
[I/OAT]: Add a sysctl for tuning the I/OAT offloaded I/O threshold Any socket recv of less than this ammount will not be offloaded Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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#
15d99e02 |
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20-Mar-2006 |
Rick Jones <rick.jones2@hp.com> |
[TCP]: sysctl to allow TCP window > 32767 sans wscale Back in the dark ages, we had to be conservative and only allow 15-bit window fields if the window scale option was not negotiated. Some ancient stacks used a signed 16-bit quantity for the window field of the TCP header and would get confused. Those days are long gone, so we can use the full 16-bits by default now. There is a sysctl added so that we can still interact with such old stacks Signed-off-by: Rick Jones <rick.jones2@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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5d424d5a |
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20-Mar-2006 |
John Heffner <jheffner@psc.edu> |
[TCP]: MTU probing Implementation of packetization layer path mtu discovery for TCP, based on the internet-draft currently found at <http://www.ietf.org/internet-drafts/draft-ietf-pmtud-method-05.txt>. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
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14c85021 |
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26-Dec-2005 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[INET_SOCK]: Move struct inet_sock & helper functions to net/inet_sock.h To help in reducing the number of include dependencies, several files were touched as they were getting needed headers indirectly for stuff they use. Thanks also to Alan Menegotto for pointing out that net/dccp/proto.c had linux/dccp.h include twice. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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89cee8b1 |
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14-Dec-2005 |
Herbert Xu <herbert@gondor.apana.org.au> |
[IPV4]: Safer reassembly Another spin of Herbert Xu's "safer ip reassembly" patch for 2.6.16. (The original patch is here: http://marc.theaimsgroup.com/?l=linux-netdev&m=112281936522415&w=2 and my only contribution is to have tested it.) This patch (optionally) does additional checks before accepting IP fragments, which can greatly reduce the possibility of reassembling fragments which originated from different IP datagrams. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Arthur Kepner <akepner@sgi.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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9772efb9 |
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10-Nov-2005 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: Appropriate Byte Count support This is an updated version of the RFC3465 ABC patch originally for Linux 2.6.11-rc4 by Yee-Ting Li. ABC is a way of counting bytes ack'd rather than packets when updating congestion control. The orignal ABC described in the RFC applied to a Reno style algorithm. For advanced congestion control there is little change after leaving slow start. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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20380731 |
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15-Aug-2005 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[NET]: Fix sparse warnings Of this type, mostly: CHECK net/ipv6/netfilter.c net/ipv6/netfilter.c:96:12: warning: symbol 'ipv6_netfilter_init' was not declared. Should it be static? net/ipv6/netfilter.c:101:6: warning: symbol 'ipv6_netfilter_fini' was not declared. Should it be static? Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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295ff7ed |
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09-Aug-2005 |
Arnaldo Carvalho de Melo <acme@mandriva.com> |
[TIMEWAIT]: Introduce inet_timewait_death_row That groups all of the tables and variables associated to the TCP timewait schedulling/recycling/killing code, that now can be isolated from the TCP specific code and used by other transport protocols, such as DCCP. Next changeset will move this code to net/ipv4/inet_timewait_sock.c Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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317a76f9 |
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23-Jun-2005 |
Stephen Hemminger <shemminger@osdl.org> |
[TCP]: Add pluggable congestion control algorithm infrastructure. Allow TCP to have multiple pluggable congestion control algorithms. Algorithms are defined by a set of operations and can be built in or modules. The legacy "new RENO" algorithm is used as a starting point and fallback. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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1c2fb7f9 |
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13-Jun-2005 |
J. Simonetti <jeroen@simonetti.nl> |
[IPV4]: Sysctl configurable icmp error source address. This patch alows you to change the source address of icmp error messages. It applies cleanly to 2.6.11.11 and retains the default behaviour. In the old (default) behaviour icmp error messages are sent with the ip of the exiting interface. The new behaviour (when the sysctl variable is toggled on), it will send the message with the ip of the interface that received the packet that caused the icmp error. This is the behaviour network administrators will expect from a router. It makes debugging complicated network layouts much easier. Also, all 'vendor routers' I know of have the later behaviour. Signed-off-by: David S. Miller <davem@davemloft.net>
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1da177e4 |
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16-Apr-2005 |
Linus Torvalds <torvalds@ppc970.osdl.org> |
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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