openvswitch: reduce stack usage in do_execute_actions

do_execute_actions() function can be called recursively multiple
times while executing actions that require pipeline forking or
recirculations. It may also be re-entered multiple times if the packet
leaves openvswitch module and re-enters it through a different port.

Currently, there is a 256-byte array allocated on stack in this
function that is supposed to hold NSH header. Compilers tend to
pre-allocate that space right at the beginning of the function:

a88: 48 81 ec b0 01 00 00 sub $0x1b0,%rsp

NSH is not a very common protocol, but the space is allocated on every
recursive call or re-entry multiplying the wasted stack space.

Move the stack allocation to push_nsh() function that is only used
if NSH actions are actually present. push_nsh() is also a simple
function without a possibility for re-entry, so the stack is returned
right away.

With this change the preallocated space is reduced by 256 B per call:

b18: 48 81 ec b0 00 00 00 sub $0xb0,%rsp

Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Eelco Chaudron echaudro@redhat.com
Reviewed-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: dst: remove unnecessary input parameter in dst_alloc and dst_init

Since commit 1202cdd66531("Remove DECnet support from kernel") has been
merged, all callers pass in the initial_ref value of 1 when they call
dst_alloc(). Therefore, remove initial_ref when the dst_alloc() is
declared and replace initial_ref with 1 in dst_alloc().
Also when all callers call dst_init(), the value of initial_ref is 1.
Therefore, remove the input parameter initial_ref of the dst_init() and
replace initial_ref with the value 1 in dst_init.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Link: https://lore.kernel.org/r/20230911125045.346390-1-shaozhengchao@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: openvswitch: add misc error drop reasons

Use drop reasons from include/net/dropreason-core.h when a reasonable
candidate exists.

Acked-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: add meter drop reason

By using an independent drop reason it makes it easy to distinguish
between QoS-triggered or flow-triggered drop.

Acked-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: add explicit drop action

From: Eric Garver <eric@garver.life>

This adds an explicit drop action. This is used by OVS to drop packets
for which it cannot determine what to do. An explicit action in the
kernel allows passing the reason _why_ the packet is being dropped or
zero to indicate no particular error happened (i.e: OVS intentionally
dropped the packet).

Since the error codes coming from userspace mean nothing for the kernel,
we squash all of them into only two drop reasons:
- OVS_DROP_EXPLICIT_WITH_ERROR to indicate a non-zero value was passed
- OVS_DROP_EXPLICIT to indicate a zero value was passed (no error)

e.g. trace all OVS dropped skbs

# perf trace -e skb:kfree_skb --filter="reason >= 0x30000"
[..]
106.023 ping/2465 skb:kfree_skb(skbaddr: 0xffffa0e8765f2000, \
location:0xffffffffc0d9b462, protocol: 2048, reason: 196611)

reason: 196611 --> 0x30003 (OVS_DROP_EXPLICIT)

Also, this patch allows ovs-dpctl.py to add explicit drop actions as:
"drop" -> implicit empty-action drop
"drop(0)" -> explicit non-error action drop
"drop(42)" -> explicit error action drop

Signed-off-by: Eric Garver <eric@garver.life>
Co-developed-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: add action error drop reason

Add a drop reason for packets that are dropped because an action
returns a non-zero error code.

Acked-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: add last-action drop reason

Create a new drop reason subsystem for openvswitch and add the first
drop reason to represent last-action drops.

Last-action drops happen when a flow has an empty action list or there
is no action that consumes the packet (output, userspace, recirc, etc).
It is the most common way in which OVS drops packets.

Implementation-wise, most of these skb-consuming actions already call
"consume_skb" internally and return directly from within the
do_execute_actions() loop so with minimal changes we can assume that
any skb that exits the loop normally is a packet drop.

Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: add support for l4 symmetric hashing

Since its introduction, the ovs module execute_hash action allowed
hash algorithms other than the skb->l4_hash to be used. However,
additional hash algorithms were not implemented. This means flows
requiring different hash distributions weren't able to use the
kernel datapath.

Now, introduce support for symmetric hashing algorithm as an
alternative hash supported by the ovs module using the flow
dissector.

Output of flow using l4_sym hash:

recirc_id(0),in_port(3),eth(),eth_type(0x0800),
ipv4(dst=64.0.0.0/192.0.0.0,proto=6,frag=no), packets:30473425,
bytes:45902883702, used:0.000s, flags:SP.,
actions:hash(sym_l4(0)),recirc(0xd)

Some performance testing with no GRO/GSO, two veths, single flow:

hash(l4(0)): 4.35 GBits/s
hash(l4_sym(0)): 4.24 GBits/s

Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: move gso declarations and functions to their own files

Move declarations into include/net/gso.h and code into net/core/gso.c

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230608191738.3947077-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: openvswitch: fix race on port output

assume the following setup on a single machine:
1. An openvswitch instance with one bridge and default flows
2. two network namespaces "server" and "client"
3. two ovs interfaces "server" and "client" on the bridge
4. for each ovs interface a veth pair with a matching name and 32 rx and
tx queues
5. move the ends of the veth pairs to the respective network namespaces
6. assign ip addresses to each of the veth ends in the namespaces (needs
to be the same subnet)
7. start some http server on the server network namespace
8. test if a client in the client namespace can reach the http server

when following the actions below the host has a chance of getting a cpu
stuck in a infinite loop:
1. send a large amount of parallel requests to the http server (around
3000 curls should work)
2. in parallel delete the network namespace (do not delete interfaces or
stop the server, just kill the namespace)

there is a low chance that this will cause the below kernel cpu stuck
message. If this does not happen just retry.
Below there is also the output of bpftrace for the functions mentioned
in the output.

The series of events happening here is:
1. the network namespace is deleted calling
`unregister_netdevice_many_notify` somewhere in the process
2. this sets first `NETREG_UNREGISTERING` on both ends of the veth and
then runs `synchronize_net`
3. it then calls `call_netdevice_notifiers` with `NETDEV_UNREGISTER`
4. this is then handled by `dp_device_event` which calls
`ovs_netdev_detach_dev` (if a vport is found, which is the case for
the veth interface attached to ovs)
5. this removes the rx_handlers of the device but does not prevent
packages to be sent to the device
6. `dp_device_event` then queues the vport deletion to work in
background as a ovs_lock is needed that we do not hold in the
unregistration path
7. `unregister_netdevice_many_notify` continues to call
`netdev_unregister_kobject` which sets `real_num_tx_queues` to 0
8. port deletion continues (but details are not relevant for this issue)
9. at some future point the background task deletes the vport

If after 7. but before 9. a packet is send to the ovs vport (which is
not deleted at this point in time) which forwards it to the
`dev_queue_xmit` flow even though the device is unregistering.
In `skb_tx_hash` (which is called in the `dev_queue_xmit`) path there is
a while loop (if the packet has a rx_queue recorded) that is infinite if
`dev->real_num_tx_queues` is zero.

To prevent this from happening we update `do_output` to handle devices
without carrier the same as if the device is not found (which would
be the code path after 9. is done).

Additionally we now produce a warning in `skb_tx_hash` if we will hit
the infinite loop.

bpftrace (first word is function name):

__dev_queue_xmit server: real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1
netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1
dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 2, reg_state: 1
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 6, reg_state: 2
ovs_netdev_detach_dev server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, reg_state: 2
netdev_rx_handler_unregister server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
netdev_rx_handler_unregister ret server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2
dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 27, reg_state: 2
dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 22, reg_state: 2
dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 18, reg_state: 2
netdev_unregister_kobject: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024
synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024
ovs_vport_send server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2
__dev_queue_xmit server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2
netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2
broken device server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024
ovs_dp_detach_port server: real_num_tx_queues: 0 cpu 9, pid: 9124, tid: 9124, reg_state: 2
synchronize_rcu_expedited: cpu 9, pid: 33604, tid: 33604

stuck message:

watchdog: BUG: soft lockup - CPU#5 stuck for 26s! [curl:1929279]
Modules linked in: veth pktgen bridge stp llc ip_set_hash_net nft_counter xt_set nft_compat nf_tables ip_set_hash_ip ip_set nfnetlink_cttimeout nfnetlink openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 tls binfmt_misc nls_iso8859_1 input_leds joydev serio_raw dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua sch_fq_codel drm efi_pstore virtio_rng ip_tables x_tables autofs4 btrfs blake2b_generic zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear hid_generic usbhid hid crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel virtio_net ahci net_failover crypto_simd cryptd psmouse libahci virtio_blk failover
CPU: 5 PID: 1929279 Comm: curl Not tainted 5.15.0-67-generic #74-Ubuntu
Hardware name: OpenStack Foundation OpenStack Nova, BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:netdev_pick_tx+0xf1/0x320
Code: 00 00 8d 48 ff 0f b7 c1 66 39 ca 0f 86 e9 01 00 00 45 0f b7 ff 41 39 c7 0f 87 5b 01 00 00 44 29 f8 41 39 c7 0f 87 4f 01 00 00 <eb> f2 0f 1f 44 00 00 49 8b 94 24 28 04 00 00 48 85 d2 0f 84 53 01
RSP: 0018:ffffb78b40298820 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff9c8773adc2e0 RCX: 000000000000083f
RDX: 0000000000000000 RSI: ffff9c8773adc2e0 RDI: ffff9c870a25e000
RBP: ffffb78b40298858 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff9c870a25e000
R13: ffff9c870a25e000 R14: ffff9c87fe043480 R15: 0000000000000000
FS: 00007f7b80008f00(0000) GS:ffff9c8e5f740000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7b80f6a0b0 CR3: 0000000329d66000 CR4: 0000000000350ee0
Call Trace:
<IRQ>
netdev_core_pick_tx+0xa4/0xb0
__dev_queue_xmit+0xf8/0x510
? __bpf_prog_exit+0x1e/0x30
dev_queue_xmit+0x10/0x20
ovs_vport_send+0xad/0x170 [openvswitch]
do_output+0x59/0x180 [openvswitch]
do_execute_actions+0xa80/0xaa0 [openvswitch]
? kfree+0x1/0x250
? kfree+0x1/0x250
? kprobe_perf_func+0x4f/0x2b0
? flow_lookup.constprop.0+0x5c/0x110 [openvswitch]
ovs_execute_actions+0x4c/0x120 [openvswitch]
ovs_dp_process_packet+0xa1/0x200 [openvswitch]
? ovs_ct_update_key.isra.0+0xa8/0x120 [openvswitch]
? ovs_ct_fill_key+0x1d/0x30 [openvswitch]
? ovs_flow_key_extract+0x2db/0x350 [openvswitch]
ovs_vport_receive+0x77/0xd0 [openvswitch]
? __htab_map_lookup_elem+0x4e/0x60
? bpf_prog_680e8aff8547aec1_kfree+0x3b/0x714
? trace_call_bpf+0xc8/0x150
? kfree+0x1/0x250
? kfree+0x1/0x250
? kprobe_perf_func+0x4f/0x2b0
? kprobe_perf_func+0x4f/0x2b0
? __mod_memcg_lruvec_state+0x63/0xe0
netdev_port_receive+0xc4/0x180 [openvswitch]
? netdev_port_receive+0x180/0x180 [openvswitch]
netdev_frame_hook+0x1f/0x40 [openvswitch]
__netif_receive_skb_core.constprop.0+0x23d/0xf00
__netif_receive_skb_one_core+0x3f/0xa0
__netif_receive_skb+0x15/0x60
process_backlog+0x9e/0x170
__napi_poll+0x33/0x180
net_rx_action+0x126/0x280
? ttwu_do_activate+0x72/0xf0
__do_softirq+0xd9/0x2e7
? rcu_report_exp_cpu_mult+0x1b0/0x1b0
do_softirq+0x7d/0xb0
</IRQ>
<TASK>
__local_bh_enable_ip+0x54/0x60
ip_finish_output2+0x191/0x460
__ip_finish_output+0xb7/0x180
ip_finish_output+0x2e/0xc0
ip_output+0x78/0x100
? __ip_finish_output+0x180/0x180
ip_local_out+0x5e/0x70
__ip_queue_xmit+0x184/0x440
? tcp_syn_options+0x1f9/0x300
ip_queue_xmit+0x15/0x20
__tcp_transmit_skb+0x910/0x9c0
? __mod_memcg_state+0x44/0xa0
tcp_connect+0x437/0x4e0
? ktime_get_with_offset+0x60/0xf0
tcp_v4_connect+0x436/0x530
__inet_stream_connect+0xd4/0x3a0
? kprobe_perf_func+0x4f/0x2b0
? aa_sk_perm+0x43/0x1c0
inet_stream_connect+0x3b/0x60
__sys_connect_file+0x63/0x70
__sys_connect+0xa6/0xd0
? setfl+0x108/0x170
? do_fcntl+0xe8/0x5a0
__x64_sys_connect+0x18/0x20
do_syscall_64+0x5c/0xc0
? __x64_sys_fcntl+0xa9/0xd0
? exit_to_user_mode_prepare+0x37/0xb0
? syscall_exit_to_user_mode+0x27/0x50
? do_syscall_64+0x69/0xc0
? __sys_setsockopt+0xea/0x1e0
? exit_to_user_mode_prepare+0x37/0xb0
? syscall_exit_to_user_mode+0x27/0x50
? __x64_sys_setsockopt+0x1f/0x30
? do_syscall_64+0x69/0xc0
? irqentry_exit+0x1d/0x30
? exc_page_fault+0x89/0x170
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f7b8101c6a7
Code: 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 18 89 54 24 0c 48 89 34 24 89
RSP: 002b:00007ffffd6b2198 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7b8101c6a7
RDX: 0000000000000010 RSI: 00007ffffd6b2360 RDI: 0000000000000005
RBP: 0000561f1370d560 R08: 00002795ad21d1ac R09: 0030312e302e302e
R10: 00007ffffd73f080 R11: 0000000000000246 R12: 0000561f1370c410
R13: 0000000000000000 R14: 0000000000000005 R15: 0000000000000000
</TASK>

Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action")
Co-developed-by: Luca Czesla <luca.czesla@mail.schwarz>
Signed-off-by: Luca Czesla <luca.czesla@mail.schwarz>
Signed-off-by: Felix Huettner <felix.huettner@mail.schwarz>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/ZC0pBXBAgh7c76CA@kernel-bug-kernel-bug
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

treewide: use get_random_u32() when possible

The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. The same also applies to get_random_int(), which is
just a wrapper around get_random_u32(). This was done as a basic find
and replace.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake
Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Acked-by: Helge Deller <deller@gmx.de> # for parisc
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

net: openvswitch: fix misuse of the cached connection on tuple changes

If packet headers changed, the cached nfct is no longer relevant
for the packet and attempt to re-use it leads to the incorrect packet
classification.

This issue is causing broken connectivity in OpenStack deployments
with OVS/OVN due to hairpin traffic being unexpectedly dropped.

The setup has datapath flows with several conntrack actions and tuple
changes between them:

actions:ct(commit,zone=8,mark=0/0x1,nat(src)),
set(eth(src=00:00:00:00:00:01,dst=00:00:00:00:00:06)),
set(ipv4(src=172.18.2.10,dst=192.168.100.6,ttl=62)),
ct(zone=8),recirc(0x4)

After the first ct() action the packet headers are almost fully
re-written. The next ct() tries to re-use the existing nfct entry
and marks the packet as invalid, so it gets dropped later in the
pipeline.

Clearing the cached conntrack entry whenever packet tuple is changed
to avoid the issue.

The flow key should not be cleared though, because we should still
be able to match on the ct_state if the recirculation happens after
the tuple change but before the next ct() action.

Cc: stable@vger.kernel.org
Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action")
Reported-by: Frode Nordahl <frode.nordahl@canonical.com>
Link: https://mail.openvswitch.org/pipermail/ovs-discuss/2022-May/051829.html
Link: https://bugs.launchpad.net/ubuntu/+source/ovn/+bug/1967856
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Link: https://lore.kernel.org/r/20220606221140.488984-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: openvswitch: don't send internal clone attribute to the userspace.

'OVS_CLONE_ATTR_EXEC' is an internal attribute that is used for
performance optimization inside the kernel. It's added by the kernel
while parsing user-provided actions and should not be sent during the
flow dump as it's not part of the uAPI.

The issue doesn't cause any significant problems to the ovs-vswitchd
process, because reported actions are not really used in the
application lifecycle and only supposed to be shown to a human via
ovs-dpctl flow dump. However, the action list is still incorrect
and causes the following error if the user wants to look at the
datapath flows:

# ovs-dpctl add-dp system@ovs-system
# ovs-dpctl add-flow "<flow match>" "clone(ct(commit),0)"
# ovs-dpctl dump-flows
<flow match>, packets:0, bytes:0, used:never,
actions:clone(bad length 4, expected -1 for: action0(01 00 00 00),
ct(commit),0)

With the fix:

# ovs-dpctl dump-flows
<flow match>, packets:0, bytes:0, used:never,
actions:clone(ct(commit),0)

Additionally fixed an incorrect attribute name in the comment.

Fixes: b233504033db ("openvswitch: kernel datapath clone action")
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Acked-by: Aaron Conole <aconole@redhat.com>
Link: https://lore.kernel.org/r/20220404104150.2865736-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

openvswitch: Add recirc_id to recirc warning

When hitting the recirculation limit, the kernel would currently log
something like this:

[ 58.586597] openvswitch: ovs-system: deferred action limit reached, drop recirc action

Which isn't all that useful to debug as we only have the interface name
to go on but can't track it down to a specific flow.

With this change, we now instead get:

[ 58.586597] openvswitch: ovs-system: deferred action limit reached, drop recirc action (recirc_id=0x9e)

Which can now be correlated with the flow entries from OVS.

Suggested-by: Frode Nordahl <frode.nordahl@canonical.com>
Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Tested-by: Stephane Graber <stgraber@ubuntu.com>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Link: https://lore.kernel.org/r/20220330194244.3476544-1-stgraber@ubuntu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

openvswitch: Fix setting ipv6 fields causing hw csum failure

Ipv6 ttl, label and tos fields are modified without first
pulling/pushing the ipv6 header, which would have updated
the hw csum (if available). This might cause csum validation
when sending the packet to the stack, as can be seen in
the trace below.

Fix this by updating skb->csum if available.

Trace resulted by ipv6 ttl dec and then sending packet
to conntrack [actions: set(ipv6(hlimit=63)),ct(zone=99)]:
[295241.900063] s_pf0vf2: hw csum failure
[295241.923191] Call Trace:
[295241.925728] <IRQ>
[295241.927836] dump_stack+0x5c/0x80
[295241.931240] __skb_checksum_complete+0xac/0xc0
[295241.935778] nf_conntrack_tcp_packet+0x398/0xba0 [nf_conntrack]
[295241.953030] nf_conntrack_in+0x498/0x5e0 [nf_conntrack]
[295241.958344] __ovs_ct_lookup+0xac/0x860 [openvswitch]
[295241.968532] ovs_ct_execute+0x4a7/0x7c0 [openvswitch]
[295241.979167] do_execute_actions+0x54a/0xaa0 [openvswitch]
[295242.001482] ovs_execute_actions+0x48/0x100 [openvswitch]
[295242.006966] ovs_dp_process_packet+0x96/0x1d0 [openvswitch]
[295242.012626] ovs_vport_receive+0x6c/0xc0 [openvswitch]
[295242.028763] netdev_frame_hook+0xc0/0x180 [openvswitch]
[295242.034074] __netif_receive_skb_core+0x2ca/0xcb0
[295242.047498] netif_receive_skb_internal+0x3e/0xc0
[295242.052291] napi_gro_receive+0xba/0xe0
[295242.056231] mlx5e_handle_rx_cqe_mpwrq_rep+0x12b/0x250 [mlx5_core]
[295242.062513] mlx5e_poll_rx_cq+0xa0f/0xa30 [mlx5_core]
[295242.067669] mlx5e_napi_poll+0xe1/0x6b0 [mlx5_core]
[295242.077958] net_rx_action+0x149/0x3b0
[295242.086762] __do_softirq+0xd7/0x2d6
[295242.090427] irq_exit+0xf7/0x100
[295242.093748] do_IRQ+0x7f/0xd0
[295242.096806] common_interrupt+0xf/0xf
[295242.100559] </IRQ>
[295242.102750] RIP: 0033:0x7f9022e88cbd
[295242.125246] RSP: 002b:00007f9022282b20 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffda
[295242.132900] RAX: 0000000000000005 RBX: 0000000000000010 RCX: 0000000000000000
[295242.140120] RDX: 00007f9022282ba8 RSI: 00007f9022282a30 RDI: 00007f9014005c30
[295242.147337] RBP: 00007f9014014d60 R08: 0000000000000020 R09: 00007f90254a8340
[295242.154557] R10: 00007f9022282a28 R11: 0000000000000246 R12: 0000000000000000
[295242.161775] R13: 00007f902308c000 R14: 000000000000002b R15: 00007f9022b71f40

Fixes: 3fdbd1ce11e5 ("openvswitch: add ipv6 'set' action")
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Link: https://lore.kernel.org/r/20220223163416.24096-1-paulb@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

openvswitch: fix alignment issues

Signed-off-by: Mark Gray <mark.d.gray@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Introduce per-cpu upcall dispatch

The Open vSwitch kernel module uses the upcall mechanism to send
packets from kernel space to user space when it misses in the kernel
space flow table. The upcall sends packets via a Netlink socket.
Currently, a Netlink socket is created for every vport. In this way,
there is a 1:1 mapping between a vport and a Netlink socket.
When a packet is received by a vport, if it needs to be sent to
user space, it is sent via the corresponding Netlink socket.

This mechanism, with various iterations of the corresponding user
space code, has seen some limitations and issues:

* On systems with a large number of vports, there is a correspondingly
large number of Netlink sockets which can limit scaling.
(https://bugzilla.redhat.com/show_bug.cgi?id=1526306)
* Packet reordering on upcalls.
(https://bugzilla.redhat.com/show_bug.cgi?id=1844576)
* A thundering herd issue.
(https://bugzilla.redhat.com/show_bug.cgi?id=1834444)

This patch introduces an alternative, feature-negotiated, upcall
mode using a per-cpu dispatch rather than a per-vport dispatch.

In this mode, the Netlink socket to be used for the upcall is
selected based on the CPU of the thread that is executing the upcall.
In this way, it resolves the issues above as:

a) The number of Netlink sockets scales with the number of CPUs
rather than the number of vports.
b) Ordering per-flow is maintained as packets are distributed to
CPUs based on mechanisms such as RSS and flows are distributed
to a single user space thread.
c) Packets from a flow can only wake up one user space thread.

The corresponding user space code can be found at:
https://mail.openvswitch.org/pipermail/ovs-dev/2021-July/385139.html

Bugzilla: https://bugzilla.redhat.com/1844576
Signed-off-by: Mark Gray <mark.d.gray@redhat.com>
Acked-by: Flavio Leitner <fbl@sysclose.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: add trace points

This makes openvswitch module use the event tracing framework
to log the upcall interface and action execution pipeline. When
using openvswitch as the packet forwarding engine, some types of
debugging are made possible simply by using the ovs-vswitchd's
ofproto/trace command. However, such a command has some
limitations:

1. When trying to trace packets that go through the CT action,
the state of the packet can't be determined, and probably
would be potentially wrong.

2. Deducing problem packets can sometimes be difficult as well
even if many of the flows are known

3. It's possible to use the openvswitch module even without
the ovs-vswitchd (although, not common use).

Introduce the event tracing points here to make it possible for
working through these problems in kernel space. The style is
copied from the mac80211 driver-trace / trace code for
consistency - this creates some checkpatch splats, but the
official 'guide' for adding tracepoints, as well as the existing
examples all add the same splats so it seems acceptable.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: fix stack OOB read while fragmenting IPv4 packets

running openvswitch on kernels built with KASAN, it's possible to see the
following splat while testing fragmentation of IPv4 packets:

BUG: KASAN: stack-out-of-bounds in ip_do_fragment+0x1b03/0x1f60
Read of size 1 at addr ffff888112fc713c by task handler2/1367

CPU: 0 PID: 1367 Comm: handler2 Not tainted 5.12.0-rc6+ #418
Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
Call Trace:
dump_stack+0x92/0xc1
print_address_description.constprop.7+0x1a/0x150
kasan_report.cold.13+0x7f/0x111
ip_do_fragment+0x1b03/0x1f60
ovs_fragment+0x5bf/0x840 [openvswitch]
do_execute_actions+0x1bd5/0x2400 [openvswitch]
ovs_execute_actions+0xc8/0x3d0 [openvswitch]
ovs_packet_cmd_execute+0xa39/0x1150 [openvswitch]
genl_family_rcv_msg_doit.isra.15+0x227/0x2d0
genl_rcv_msg+0x287/0x490
netlink_rcv_skb+0x120/0x380
genl_rcv+0x24/0x40
netlink_unicast+0x439/0x630
netlink_sendmsg+0x719/0xbf0
sock_sendmsg+0xe2/0x110
____sys_sendmsg+0x5ba/0x890
___sys_sendmsg+0xe9/0x160
__sys_sendmsg+0xd3/0x170
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f957079db07
Code: c3 66 90 41 54 41 89 d4 55 48 89 f5 53 89 fb 48 83 ec 10 e8 eb ec ff ff 44 89 e2 48 89 ee 89 df 41 89 c0 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 48 89 44 24 08 e8 24 ed ff ff 48
RSP: 002b:00007f956ce35a50 EFLAGS: 00000293 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000019 RCX: 00007f957079db07
RDX: 0000000000000000 RSI: 00007f956ce35ae0 RDI: 0000000000000019
RBP: 00007f956ce35ae0 R08: 0000000000000000 R09: 00007f9558006730
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f956ce37308 R14: 00007f956ce35f80 R15: 00007f956ce35ae0

The buggy address belongs to the page:
page:00000000af2a1d93 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x112fc7
flags: 0x17ffffc0000000()
raw: 0017ffffc0000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

addr ffff888112fc713c is located in stack of task handler2/1367 at offset 180 in frame:
ovs_fragment+0x0/0x840 [openvswitch]

this frame has 2 objects:
[32, 144) 'ovs_dst'
[192, 424) 'ovs_rt'

Memory state around the buggy address:
ffff888112fc7000: f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888112fc7080: 00 f1 f1 f1 f1 00 00 00 00 00 00 00 00 00 00 00
>ffff888112fc7100: 00 00 00 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00
^
ffff888112fc7180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888112fc7200: 00 00 00 00 00 00 f2 f2 f2 00 00 00 00 00 00 00

for IPv4 packets, ovs_fragment() uses a temporary struct dst_entry. Then,
in the following call graph:

ip_do_fragment()
ip_skb_dst_mtu()
ip_dst_mtu_maybe_forward()
ip_mtu_locked()

the pointer to struct dst_entry is used as pointer to struct rtable: this
turns the access to struct members like rt_mtu_locked into an OOB read in
the stack. Fix this changing the temporary variable used for IPv4 packets
in ovs_fragment(), similarly to what is done for IPv6 few lines below.

Fixes: d52e5a7e7ca4 ("ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmt")
Cc: <stable@vger.kernel.org>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: add log message for error case

As requested by upstream OVS, added some error messages in the
validate_and_copy_dec_ttl function.

Includes a small cleanup, which removes an unnecessary parameter
from the dec_ttl_exception_handler() function.

Reported-by: Flavio Leitner <fbl@sysclose.org>
Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Acked-by: Flavio Leitner <fbl@sysclose.org>
Link: https://lore.kernel.org/r/161054576573.26637.18396634650212670580.stgit@ebuild
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: openvswitch: fix TTL decrement exception action execution

Currently, the exception actions are not processed correctly as the wrong
dataset is passed. This change fixes this, including the misleading
comment.

In addition, a check was added to make sure we work on an IPv4 packet,
and not just assume if it's not IPv6 it's IPv4.

This was all tested using OVS with patch,
https://patchwork.ozlabs.org/project/openvswitch/list/?series=21639,
applied and sending packets with a TTL of 1 (and 0), both with IPv4
and IPv6.

Fixes: 69929d4c49e1 ("net: openvswitch: fix TTL decrement action netlink message format")
Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Link: https://lore.kernel.org/r/160733569860.3007.12938188180387116741.stgit@wsfd-netdev64.ntdv.lab.eng.bos.redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: openvswitch: ensure LSE is pullable before reading it

when openvswitch is configured to mangle the LSE, the current value is
read from the packet dereferencing 4 bytes at mpls_hdr(): ensure that
the label is contained in the skb "linear" area.

Found by code inspection.

Fixes: d27cf5c59a12 ("net: core: add MPLS update core helper and use in OvS")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Link: https://lore.kernel.org/r/aa099f245d93218b84b5c056b67b6058ccf81a66.1606987185.git.dcaratti@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: openvswitch: fix TTL decrement action netlink message format

Currently, the openvswitch module is not accepting the correctly formated
netlink message for the TTL decrement action. For both setting and getting
the dec_ttl action, the actions should be nested in the
OVS_DEC_TTL_ATTR_ACTION attribute as mentioned in the openvswitch.h uapi.

When the original patch was sent, it was tested with a private OVS userspace
implementation. This implementation was unfortunately not upstreamed and
reviewed, hence an erroneous version of this patch was sent out.

Leaving the patch as-is would cause problems as the kernel module could
interpret additional attributes as actions and vice-versa, due to the
actions not being encapsulated/nested within the actual attribute, but
being concatinated after it.

Fixes: 744676e77720 ("openvswitch: add TTL decrement action")
Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Link: https://lore.kernel.org/r/160622121495.27296.888010441924340582.stgit@wsfd-netdev64.ntdv.lab.eng.bos.redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/sched: act_vlan: Add {POP,PUSH}_ETH actions

Implement TCA_VLAN_ACT_POP_ETH and TCA_VLAN_ACT_PUSH_ETH, to
respectively pop and push a base Ethernet header at the beginning of a
frame.

POP_ETH is just a matter of pulling ETH_HLEN bytes. VLAN tags, if any,
must be stripped before calling POP_ETH.

PUSH_ETH is restricted to skbs with no mac_header, and only the MAC
addresses can be configured. The Ethertype is automatically set from
skb->protocol. These restrictions ensure that all skb's fields remain
consistent, so that this action can't confuse other part of the
networking stack (like GSO).

Since openvswitch already had these actions, consolidate the code in
skbuff.c (like for vlan and mpls push/pop).

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: improve the coding style

Not change the logic, just improve the coding style.

Cc: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: using ip6_fragment in ipv6_stub

Using ipv6_stub->ipv6_fragment to avoid the netfilter dependency

Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: take into account de-fragmentation/gso_size in execute_check_pkt_len

ovs connection tracking module performs de-fragmentation on incoming
fragmented traffic. Take info account if traffic has been de-fragmented
in execute_check_pkt_len action otherwise we will perform the wrong
nested action considering the original packet size. This issue typically
occurs if ovs-vswitchd adds a rule in the pipeline that requires connection
tracking (e.g. OVN stateful ACLs) before execute_check_pkt_len action.
Moreover take into account GSO fragment size for GSO packet in
execute_check_pkt_len routine

Fixes: 4d5ec89fc8d14 ("net: openvswitch: Add a new action check_pkt_len")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: add TTL decrement action

New action to decrement TTL instead of setting it to a fixed value.
This action will decrement the TTL and, in case of expired TTL, drop it
or execute an action passed via a nested attribute.
The default TTL expired action is to drop the packet.

Supports both IPv4 and IPv6 via the ttl and hop_limit fields, respectively.

Tested with a corresponding change in the userspace:

# ovs-dpctl dump-flows
in_port(2),eth(),eth_type(0x0800), packets:0, bytes:0, used:never, actions:dec_ttl{ttl<=1 action:(drop)},1
in_port(1),eth(),eth_type(0x0800), packets:0, bytes:0, used:never, actions:dec_ttl{ttl<=1 action:(drop)},2
in_port(1),eth(),eth_type(0x0806), packets:0, bytes:0, used:never, actions:2
in_port(2),eth(),eth_type(0x0806), packets:0, bytes:0, used:never, actions:1

# ping -c1 192.168.0.2 -t 42
IP (tos 0x0, ttl 41, id 61647, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.0.1 > 192.168.0.2: ICMP echo request, id 386, seq 1, length 64
# ping -c1 192.168.0.2 -t 120
IP (tos 0x0, ttl 119, id 62070, offset 0, flags [DF], proto ICMP (1), length 84)
192.168.0.1 > 192.168.0.2: ICMP echo request, id 388, seq 1, length 64
# ping -c1 192.168.0.2 -t 1
#

Co-developed-by: Bindiya Kurle <bindiyakurle@gmail.com>
Signed-off-by: Bindiya Kurle <bindiyakurle@gmail.com>
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: New MPLS actions for layer 2 tunnelling

The existing PUSH MPLS action inserts MPLS header between ethernet header
and the IP header. Though this behaviour is fine for L3 VPN where an IP
packet is encapsulated inside a MPLS tunnel, it does not suffice the L2
VPN (l2 tunnelling) requirements. In L2 VPN the MPLS header should
encapsulate the ethernet packet.

The new mpls action ADD_MPLS inserts MPLS header at the start of the
packet or at the start of the l3 header depending on the value of l3 tunnel
flag in the ADD_MPLS arguments.

POP_MPLS action is extended to support ethertype 0x6558.

Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Fixed updating of ethertype in skb_mpls_push()

The skb_mpls_push was not updating ethertype of an ethernet packet if
the packet was originally received from a non ARPHRD_ETHER device.

In the below OVS data path flow, since the device corresponding to
port 7 is an l3 device (ARPHRD_NONE) the skb_mpls_push function does
not update the ethertype of the packet even though the previous
push_eth action had added an ethernet header to the packet.

recirc_id(0),in_port(7),eth_type(0x0800),ipv4(tos=0/0xfc,ttl=64,frag=no),
actions:push_eth(src=00:00:00:00:00:00,dst=00:00:00:00:00:00),
push_mpls(label=13,tc=0,ttl=64,bos=1,eth_type=0x8847),4

Fixes: 8822e270d697 ("net: core: move push MPLS functionality from OvS to core helper")
Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixed updating of ethertype in function skb_mpls_pop

The skb_mpls_pop was not updating ethertype of an ethernet packet if the
packet was originally received from a non ARPHRD_ETHER device.

In the below OVS data path flow, since the device corresponding to port 7
is an l3 device (ARPHRD_NONE) the skb_mpls_pop function does not update
the ethertype of the packet even though the previous push_eth action had
added an ethernet header to the packet.

recirc_id(0),in_port(7),eth_type(0x8847),
mpls(label=12/0xfffff,tc=0/0,ttl=0/0x0,bos=1/1),
actions:push_eth(src=00:00:00:00:00:00,dst=00:00:00:00:00:00),
pop_mpls(eth_type=0x800),4

Fixes: ed246cee09b9 ("net: core: move pop MPLS functionality from OvS to core helper")
Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Change in Openvswitch to support MPLS label depth of 3 in ingress direction

The openvswitch was supporting a MPLS label depth of 1 in the ingress
direction though the userspace OVS supports a max depth of 3 labels.
This change enables openvswitch module to support a max depth of
3 labels in the ingress.

Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sched: fix corrupted L2 header with MPLS 'push' and 'pop' actions

the following script:

# tc qdisc add dev eth0 clsact
# tc filter add dev eth0 egress protocol ip matchall \
> action mpls push protocol mpls_uc label 0x355aa bos 1

causes corruption of all IP packets transmitted by eth0. On TC egress, we
can't rely on the value of skb->mac_len, because it's 0 and a MPLS 'push'
operation will result in an overwrite of the first 4 octets in the packet
L2 header (e.g. the Destination Address if eth0 is an Ethernet); the same
error pattern is present also in the MPLS 'pop' operation. Fix this error
in act_mpls data plane, computing 'mac_len' as the difference between the
network header and the mac header (when not at TC ingress), and use it in
MPLS 'push'/'pop' core functions.

v2: unbreak 'make htmldocs' because of missing documentation of 'mac_len'
in skb_mpls_pop(), reported by kbuild test robot

CC: Lorenzo Bianconi <lorenzo@kernel.org>
Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC")
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: core: add MPLS update core helper and use in OvS

Open vSwitch allows the updating of an existing MPLS header on a packet.
In preparation for supporting similar functionality in TC, move this to a
common skb helper function.

Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: core: move pop MPLS functionality from OvS to core helper

Open vSwitch provides code to pop an MPLS header to a packet. In
preparation for supporting this in TC, move the pop code to an skb helper
that can be reused.

Remove the, now unused, update_ethertype static function from OvS.

Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: core: move push MPLS functionality from OvS to core helper

Open vSwitch provides code to push an MPLS header to a packet. In
preparation for supporting this in TC, move the push code to an skb helper
that can be reused.

Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: fix csum updates for MPLS actions

Skbs may have their checksum value populated by HW. If this is a checksum
calculated over the entire packet then the CHECKSUM_COMPLETE field is
marked. Changes to the data pointer on the skb throughout the network
stack still try to maintain this complete csum value if it is required
through functions such as skb_postpush_rcsum.

The MPLS actions in Open vSwitch modify a CHECKSUM_COMPLETE value when
changes are made to packet data without a push or a pull. This occurs when
the ethertype of the MAC header is changed or when MPLS lse fields are
modified.

The modification is carried out using the csum_partial function to get the
csum of a buffer and add it into the larger checksum. The buffer is an
inversion of the data to be removed followed by the new data. Because the
csum is calculated over 16 bits and these values align with 16 bits, the
effect is the removal of the old value from the CHECKSUM_COMPLETE and
addition of the new value.

However, the csum fed into the function and the outcome of the
calculation are also inverted. This would only make sense if it was the
new value rather than the old that was inverted in the input buffer.

Fix the issue by removing the bit inverts in the csum_partial calculation.

The bug was verified and the fix tested by comparing the folded value of
the updated CHECKSUM_COMPLETE value with the folded value of a full
software checksum calculation (reset skb->csum to 0 and run
skb_checksum_complete(skb)). Prior to the fix the outcomes differed but
after they produce the same result.

Fixes: 25cd9ba0abc0 ("openvswitch: Add basic MPLS support to kernel")
Fixes: bc7cc5999fd3 ("openvswitch: update checksum in {push,pop}_mpls")
Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 269

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of version 2 of the gnu general public license as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 51 franklin street fifth floor boston ma
02110 1301 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 21 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141334.228102212@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: openvswitch: Add a new action check_pkt_len

This patch adds a new action - 'check_pkt_len' which checks the
packet length and executes a set of actions if the packet
length is greater than the specified length or executes
another set of actions if the packet length is lesser or equal to.

This action takes below nlattrs
* OVS_CHECK_PKT_LEN_ATTR_PKT_LEN - 'pkt_len' to check for

* OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER - Nested actions
to apply if the packet length is greater than the specified 'pkt_len'

* OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL - Nested
actions to apply if the packet length is lesser or equal to the
specified 'pkt_len'.

The main use case for adding this action is to solve the packet
drops because of MTU mismatch in OVN virtual networking solution.
When a VM (which belongs to a logical switch of OVN) sends a packet
destined to go via the gateway router and if the nic which provides
external connectivity, has a lesser MTU, OVS drops the packet
if the packet length is greater than this MTU.

With the help of this action, OVN will check the packet length
and if it is greater than the MTU size, it will generate an
ICMP packet (type 3, code 4) and includes the next hop mtu in it
so that the sender can fragment the packets.

Reported-at:
https://mail.openvswitch.org/pipermail/ovs-discuss/2018-July/047039.html
Suggested-by: Ben Pfaff <blp@ovn.org>
Signed-off-by: Numan Siddique <nusiddiq@redhat.com>
CC: Gregory Rose <gvrose8192@gmail.com>
CC: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

OVS: remove use of VLAN_TAG_PRESENT

This is a minimal change to allow removing of VLAN_TAG_PRESENT.
It leaves OVS unable to use CFI bit, as fixing this would need
a deeper surgery involving userspace interface.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: kernel datapath clone action

Add 'clone' action to kernel datapath by using existing functions.
When actions within clone don't modify the current flow, the flow
key is not cloned before executing clone actions.

This is a follow up patch for this incomplete work:
https://patchwork.ozlabs.org/patch/722096/

v1 -> v2:
Refactor as advised by reviewer.

Signed-off-by: Yifeng Sun <pkusunyifeng@gmail.com>
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Add meter action support

Implements OVS kernel meter action support.

Signed-off-by: Andy Zhou <azhou@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: enable NSH support

v16->17
- Fixed disputed check code: keep them in nsh_push and nsh_pop
but also add them in __ovs_nla_copy_actions

v15->v16
- Add csum recalculation for nsh_push, nsh_pop and set_nsh
pointed out by Pravin
- Move nsh key into the union with ipv4 and ipv6 and add
check for nsh key in match_validate pointed out by Pravin
- Add nsh check in validate_set and __ovs_nla_copy_actions

v14->v15
- Check size in nsh_hdr_from_nlattr
- Fixed four small issues pointed out By Jiri and Eric

v13->v14
- Rename skb_push_nsh to nsh_push per Dave's comment
- Rename skb_pop_nsh to nsh_pop per Dave's comment

v12->v13
- Fix NSH header length check in set_nsh

v11->v12
- Fix missing changes old comments pointed out
- Fix new comments for v11

v10->v11
- Fix the left three disputable comments for v9
but not fixed in v10.

v9->v10
- Change struct ovs_key_nsh to
struct ovs_nsh_key_base base;
__be32 context[NSH_MD1_CONTEXT_SIZE];
- Fix new comments for v9

v8->v9
- Fix build error reported by daily intel build
because nsh module isn't selected by openvswitch

v7->v8
- Rework nested value and mask for OVS_KEY_ATTR_NSH
- Change pop_nsh to adapt to nsh kernel module
- Fix many issues per comments from Jiri Benc

v6->v7
- Remove NSH GSO patches in v6 because Jiri Benc
reworked it as another patch series and they have
been merged.
- Change it to adapt to nsh kernel module added by NSH
GSO patch series

v5->v6
- Fix the rest comments for v4.
- Add NSH GSO support for VxLAN-gpe + NSH and
Eth + NSH.

v4->v5
- Fix many comments by Jiri Benc and Eric Garver
for v4.

v3->v4
- Add new NSH match field ttl
- Update NSH header to the latest format
which will be final format and won't change
per its author's confirmation.
- Fix comments for v3.

v2->v3
- Change OVS_KEY_ATTR_NSH to nested key to handle
length-fixed attributes and length-variable
attriubte more flexibly.
- Remove struct ovs_action_push_nsh completely
- Add code to handle nested attribute for SET_MASKED
- Change PUSH_NSH to use the nested OVS_KEY_ATTR_NSH
to transfer NSH header data.
- Fix comments and coding style issues by Jiri and Eric

v1->v2
- Change encap_nsh and decap_nsh to push_nsh and pop_nsh
- Dynamically allocate struct ovs_action_push_nsh for
length-variable metadata.

OVS master and 2.8 branch has merged NSH userspace
patch series, this patch is to enable NSH support
in kernel data path in order that OVS can support
NSH in compat mode by porting this.

Signed-off-by: Yi Yang <yi.y.yang@intel.com>
Acked-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Eric Garver <e@erig.me>
Acked-by: Pravin Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: add ct_clear action

This adds a ct_clear action for clearing conntrack state. ct_clear is
currently implemented in OVS userspace, but is not backed by an action
in the kernel datapath. This is useful for flows that may modify a
packet tuple after a ct lookup has already occurred.

Signed-off-by: Eric Garver <e@erig.me>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: fix skb_panic due to the incorrect actions attrlen

For sw_flow_actions, the actions_len only represents the kernel part's
size, and when we dump the actions to the userspace, we will do the
convertions, so it's true size may become bigger than the actions_len.

But unfortunately, for OVS_PACKET_ATTR_ACTIONS, we use the actions_len
to alloc the skbuff, so the user_skb's size may become insufficient and
oops will happen like this:
skbuff: skb_over_panic: text:ffffffff8148fabf len:1749 put:157 head:
ffff881300f39000 data:ffff881300f39000 tail:0x6d5 end:0x6c0 dev:<NULL>
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:129!
[...]
Call Trace:
<IRQ>
[<ffffffff8148be82>] skb_put+0x43/0x44
[<ffffffff8148fabf>] skb_zerocopy+0x6c/0x1f4
[<ffffffffa0290d36>] queue_userspace_packet+0x3a3/0x448 [openvswitch]
[<ffffffffa0292023>] ovs_dp_upcall+0x30/0x5c [openvswitch]
[<ffffffffa028d435>] output_userspace+0x132/0x158 [openvswitch]
[<ffffffffa01e6890>] ? ip6_rcv_finish+0x74/0x77 [ipv6]
[<ffffffffa028e277>] do_execute_actions+0xcc1/0xdc8 [openvswitch]
[<ffffffffa028e3f2>] ovs_execute_actions+0x74/0x106 [openvswitch]
[<ffffffffa0292130>] ovs_dp_process_packet+0xe1/0xfd [openvswitch]
[<ffffffffa0292b77>] ? key_extract+0x63c/0x8d5 [openvswitch]
[<ffffffffa029848b>] ovs_vport_receive+0xa1/0xc3 [openvswitch]
[...]

Also we can find that the actions_len is much little than the orig_len:
crash> struct sw_flow_actions 0xffff8812f539d000
struct sw_flow_actions {
rcu = {
next = 0xffff8812f5398800,
func = 0xffffe3b00035db32
},
orig_len = 1384,
actions_len = 592,
actions = 0xffff8812f539d01c
}

So as a quick fix, use the orig_len instead of the actions_len to alloc
the user_skb.

Last, this oops happened on our system running a relative old kernel, but
the same risk still exists on the mainline, since we use the wrong
actions_len from the beginning.

Fixes: ccea74457bbd ("openvswitch: include datapath actions with sampled-packet upcall to userspace")
Cc: Neil McKee <neil.mckee@inmon.com>
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Openvswitch: Refactor sample and recirc actions implementation

Added clone_execute() that both the sample and the recirc
action implementation can use.

Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Optimize sample action for the clone use cases

With the introduction of open flow 'clone' action, the OVS user space
can now translate the 'clone' action into kernel datapath 'sample'
action, with 100% probability, to ensure that the clone semantics,
which is that the packet seen by the clone action is the same as the
packet seen by the action after clone, is faithfully carried out
in the datapath.

While the sample action in the datpath has the matching semantics,
its implementation is only optimized for its original use.
Specifically, there are two limitation: First, there is a 3 level of
nesting restriction, enforced at the flow downloading time. This
limit turns out to be too restrictive for the 'clone' use case.
Second, the implementation avoid recursive call only if the sample
action list has a single userspace action.

The main optimization implemented in this series removes the static
nesting limit check, instead, implement the run time recursion limit
check, and recursion avoidance similar to that of the 'recirc' action.
This optimization solve both #1 and #2 issues above.

One related optimization attempts to avoid copying flow key as
long as the actions enclosed does not change the flow key. The
detection is performed only once at the flow downloading time.

Another related optimization is to rewrite the action list
at flow downloading time in order to save the fast path from parsing
the sample action list in its original form repeatedly.

Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Refactor recirc key allocation.

The logic of allocating and copy key for each 'exec_actions_level'
was specific to execute_recirc(). However, future patches will reuse
as well. Refactor the logic into its own function clone_key().

Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Deferred fifo API change.

add_deferred_actions() API currently requires actions to be passed in
as a fully encoded netlink message. So far both 'sample' and 'recirc'
actions happens to carry actions as fully encoded netlink messages.
However, this requirement is more restrictive than necessary, future
patch will need to pass in action lists that are not fully encoded
by themselves.

Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: actions: fixed a brace coding style warning

Fixed a brace coding style warning reported by checkpatch.pl

Signed-off-by: Peter Downs <padowns@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Add original direction conntrack tuple to sw_flow_key.

Add the fields of the conntrack original direction 5-tuple to struct
sw_flow_key. The new fields are initially marked as non-existent, and
are populated whenever a conntrack action is executed and either finds
or generates a conntrack entry. This means that these fields exist
for all packets that were not rejected by conntrack as untrackable.

The original tuple fields in the sw_flow_key are filled from the
original direction tuple of the conntrack entry relating to the
current packet, or from the original direction tuple of the master
conntrack entry, if the current conntrack entry has a master.
Generally, expected connections of connections having an assigned
helper (e.g., FTP), have a master conntrack entry.

The main purpose of the new conntrack original tuple fields is to
allow matching on them for policy decision purposes, with the premise
that the admissibility of tracked connections reply packets (as well
as original direction packets), and both direction packets of any
related connections may be based on ACL rules applying to the master
connection's original direction 5-tuple. This also makes it easier to
make policy decisions when the actual packet headers might have been
transformed by NAT, as the original direction 5-tuple represents the
packet headers before any such transformation.

When using the original direction 5-tuple the admissibility of return
and/or related packets need not be based on the mere existence of a
conntrack entry, allowing separation of admission policy from the
established conntrack state. While existence of a conntrack entry is
required for admission of the return or related packets, policy
changes can render connections that were initially admitted to be
rejected or dropped afterwards. If the admission of the return and
related packets was based on mere conntrack state (e.g., connection
being in an established state), a policy change that would make the
connection rejected or dropped would need to find and delete all
conntrack entries affected by such a change. When using the original
direction 5-tuple matching the affected conntrack entries can be
allowed to time out instead, as the established state of the
connection would not need to be the basis for packet admission any
more.

It should be noted that the directionality of related connections may
be the same or different than that of the master connection, and
neither the original direction 5-tuple nor the conntrack state bits
carry this information. If needed, the directionality of the master
connection can be stored in master's conntrack mark or labels, which
are automatically inherited by the expected related connections.

The fact that neither ARP nor ND packets are trackable by conntrack
allows mutual exclusion between ARP/ND and the new conntrack original
tuple fields. Hence, the IP addresses are overlaid in union with ARP
and ND fields. This allows the sw_flow_key to not grow much due to
this patch, but it also means that we must be careful to never use the
new key fields with ARP or ND packets. ARP is easy to distinguish and
keep mutually exclusive based on the ethernet type, but ND being an
ICMPv6 protocol requires a bit more attention.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Simplify do_execute_actions().

do_execute_actions() implements a worthwhile optimization: in case
an output action is the last action in an action list, skb_clone()
can be avoided by outputing the current skb. However, the
implementation is more complicated than necessary. This patch
simplify this logic.

Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: add Ethernet push and pop actions

It's not allowed to push Ethernet header in front of another Ethernet
header.

It's not allowed to pop Ethernet header if there's a vlan tag. This
preserves the invariant that L3 packet never has a vlan tag.

Based on previous versions by Lorand Jakab and Simon Horman.

Signed-off-by: Lorand Jakab <lojakab@cisco.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: support MPLS push and pop for L3 packets

Update Ethernet header only if there is one.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: pass mac_proto to ovs_vport_send

We'll need it to alter packets sent to ARPHRD_NONE interfaces.

Change do_output() to use the actual L2 header size of the packet when
deciding on the minimum cutlen. The assumption here is that what matters is
not the output interface hard_header_len but rather the L2 header of the
particular packet. For example, ARPHRD_NONE tunnels that encapsulate
Ethernet should get at least the Ethernet header.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: add mac_proto field to the flow key

Use a hole in the structure. We support only Ethernet so far and will add
a support for L2-less packets shortly. We could use a bool to indicate
whether the Ethernet header is present or not but the approach with the
mac_proto field is more generic and occupies the same number of bytes in the
struct, while allowing later extensibility. It also makes the code in the
next patches more self explaining.

It would be nice to use ARPHRD_ constants but those are u16 which would be
waste. Thus define our own constants.

Another upside of this is that we can overload this new field to also denote
whether the flow key is valid. This has the advantage that on
refragmentation, we don't have to reparse the packet but can rely on the
stored eth.type. This is especially important for the next patches in this
series - instead of adding another branch for L2-less packets before calling
ovs_fragment, we can just remove all those branches completely.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: use hard_header_len instead of hardcoded ETH_HLEN

On tx, use hard_header_len while deciding whether to refragment or drop the
packet. That way, all combinations are calculated correctly:

* L2 packet going to L2 interface (the L2 header len is subtracted),
* L2 packet going to L3 interface (the L2 header is included in the packet
lenght),
* L3 packet going to L3 interface.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: correctly fragment packet with mpls headers

If mpls headers were pushed to a defragmented packet, the refragmentation no
longer works correctly after 48d2ab609b6b ("net: mpls: Fixups for GSO"). The
network header has to be shifted after the mpls headers for the
fragmentation and restored afterwards.

Fixes: 48d2ab609b6b ("net: mpls: Fixups for GSO")
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: use mpls_hdr

skb_mpls_header is equivalent to mpls_hdr now. Use the existing helper
instead.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: avoid deferred execution of recirc actions

The ovs kernel data path currently defers the execution of all
recirc actions until stack utilization is at a minimum.
This is too limiting for some packet forwarding scenarios due to
the small size of the deferred action FIFO (10 entries). For
example, broadcast traffic sent out more than 10 ports with
recirculation results in packet drops when the deferred action
FIFO becomes full, as reported here:

http://openvswitch.org/pipermail/dev/2016-March/067672.html

Since the current recursion depth is available (it is already tracked
by the exec_actions_level pcpu variable), we can use it to determine
whether to execute recirculation actions immediately (safe when
recursion depth is low) or defer execution until more stack space is
available.

With this change, the deferred action fifo size becomes a non-issue
for currently failing scenarios because it is no longer used when
there are three or fewer recursions through ovs_execute_actions().

Suggested-by: Pravin Shelar <pshelar@ovn.org>
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: 802.1AD Flow handling, actions, vlan parsing, netlink attributes

Add support for 802.1ad including the ability to push and pop double
tagged vlans. Add support for 802.1ad to netlink parsing and flow
conversion. Uses double nested encap attributes to represent double
tagged vlan. Inner TPID encoded along with ctci in nested attributes.

This is based on Thomas F Herbert's original v20 patch. I made some
small clean ups and bug fixes.

Signed-off-by: Thomas F Herbert <thomasfherbert@gmail.com>
Signed-off-by: Eric Garver <e@erig.me>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: mpls: Fixups for GSO

As reported by Lennert the MPLS GSO code is failing to properly segment
large packets. There are a couple of problems:

1. the inner protocol is not set so the gso segment functions for inner
protocol layers are not getting run, and

2 MPLS labels for packets that use the "native" (non-OVS) MPLS code
are not properly accounted for in mpls_gso_segment.

The MPLS GSO code was added for OVS. It is re-using skb_mac_gso_segment
to call the gso segment functions for the higher layer protocols. That
means skb_mac_gso_segment is called twice -- once with the network
protocol set to MPLS and again with the network protocol set to the
inner protocol.

This patch sets the inner skb protocol addressing item 1 above and sets
the network_header and inner_network_header to mark where the MPLS labels
start and end. The MPLS code in OVS is also updated to set the two
network markers.

>From there the MPLS GSO code uses the difference between the network
header and the inner network header to know the size of the MPLS header
that was pushed. It then pulls the MPLS header, resets the mac_len and
protocol for the inner protocol and then calls skb_mac_gso_segment
to segment the skb.

Afterward the inner protocol segmentation is done the skb protocol
is set to mpls for each segment and the network and mac headers
restored.

Reported-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Add packet truncation support.

The patch adds a new OVS action, OVS_ACTION_ATTR_TRUNC, in order to
truncate packets. A 'max_len' is added for setting up the maximum
packet size, and a 'cutlen' field is to record the number of bytes
to trim the packet when the packet is outputting to a port, or when
the packet is sent to userspace.

Signed-off-by: William Tu <u9012063@gmail.com>
Cc: Pravin Shelar <pshelar@nicira.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: update checksum in {push,pop}_mpls

In the case of CHECKSUM_COMPLETE the skb checksum should be updated in
{push,pop}_mpls() as they the type in the ethernet header.

As suggested by Pravin Shelar.

Cc: Pravin Shelar <pshelar@nicira.com>
Fixes: 25cd9ba0abc0 ("openvswitch: Add basic MPLS support to kernel")
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: use flow protocol when recalculating ipv6 checksums

When using masked actions the ipv6_proto field of an action
to set IPv6 fields may be zero rather than the prevailing protocol
which will result in skipping checksum recalculation.

This patch resolves the problem by relying on the protocol
in the flow key rather than that in the set field action.

Fixes: 83d2b9ba1abc ("net: openvswitch: Support masked set actions.")
Cc: Jarno Rajahalme <jrajahalme@nicira.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: use skb_postpush_rcsum instead of own implementations

Replace individual implementations with the recently introduced
skb_postpush_rcsum() helper.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Tom Herbert <tom@herbertland.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

ovs: limit ovs recursions in ovs_execute_actions to not corrupt stack

It was seen that defective configurations of openvswitch could overwrite
the STACK_END_MAGIC and cause a hard crash of the kernel because of too
many recursions within ovs.

This problem arises due to the high stack usage of openvswitch. The rest
of the kernel is fine with the current limit of 10 (RECURSION_LIMIT).

We use the already existing recursion counter in ovs_execute_actions to
implement an upper bound of 5 recursions.

Cc: Pravin Shelar <pshelar@ovn.org>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Fix double-free on ip_defrag() errors

If ip_defrag() returns an error other than -EINPROGRESS, then the skb is
freed. When handle_fragments() passes this back up to
do_execute_actions(), it will be freed again. Prevent this double free
by never freeing the skb in do_execute_actions() for errors returned by
ovs_ct_execute. Always free it in ovs_ct_execute() error paths instead.

Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action")
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Fix egress tunnel info.

While transitioning to netdev based vport we broke OVS
feature which allows user to retrieve tunnel packet egress
information for lwtunnel devices. Following patch fixes it
by introducing ndo operation to get the tunnel egress info.
Same ndo operation can be used for lwtunnel devices and compat
ovs-tnl-vport devices. So after adding such device operation
we can remove similar operation from ovs-vport.

Fixes: 614732eaa12d ("openvswitch: Use regular VXLAN net_device device").
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Ensure flow is valid before executing ct

The ct action uses parts of the flow key, so we need to ensure that it
is valid before executing that action.

Fixes: 7f8a436eaa2c "openvswitch: Add conntrack action"
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Fix skb leak in ovs_fragment()

If ovs_fragment() was unable to fragment the skb due to an L2 header
that exceeds the supported length, skbs would be leaked. Fix the bug.

Fixes: 7f8a436eaa2c "openvswitch: Add conntrack action"
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Rename LABEL->LABELS

Conntrack LABELS (plural) are exposed by conntrack; rename the OVS name
for these to be consistent with conntrack.

Fixes: c2ac667 "openvswitch: Allow matching on conntrack label"
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Remove ovs_vport_output_sk

This was a compatibility function needed while the ipv4 and ipv6
fragmentation code was being modified to pass a struct net through
them. Now that is complete this function has no more users so remove
it.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

ipv6: Pass struct net through ip6_fragment

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

ipv4: Pass struct net through ip_fragment

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

openvswitch: Pass net into ovs_fragment

In preparation for the ipv4 and ipv6 fragmentation code taking a net
parameter pass a struct net into ovs_fragment where the v4 and v6
fragmentation code is called.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

openvswitch: Pass net into ovs_vport_output

When struct net starts being passed through the ipv4 and ipv6 fragment
routines ovs_vport_output will need to take a net parameter.
Prepare ovs_vport_output before that is needed and introduce
ovs_vport_output_skk for the call sites that still need the old
calling conventions.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

ip-tunnel: Use API to access tunnel metadata options.

Currently tun-info options pointer is used in few cases to
pass options around. But tunnel options can be accessed using
ip_tunnel_info_opts() API without using the pointer. Following
patch removes the redundant pointer and consistently make use
of API.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Reviewed-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Remove egress_tun_info.

tun info is passed using skb-dst pointer. Now we have
converted all vports to netdev based implementation so
Now we can remove redundant pointer to tun-info from OVS_CB.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Include ip6_fib.h.

kbuild test robot reports that certain configurations will not
automatically pick up on the "struct rt6_info" definition, so explicitly
include the header for this structure.

Fixes: 7f8a436 "openvswitch: Add conntrack action"
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Allow matching on conntrack label

Allow matching and setting the ct_label field. As with ct_mark, this is
populated by executing the CT action. The label field may be modified by
specifying a label and mask nested under the CT action. It is stored as
metadata attached to the connection. Label modification occurs after
lookup, and will only persist when the conntrack entry is committed by
providing the COMMIT flag to the CT action. Labels are currently fixed
to 128 bits in size.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Allow matching on conntrack mark

Allow matching and setting the ct_mark field. As with ct_state and
ct_zone, these fields are populated when the CT action is executed. To
write to this field, a value and mask can be specified as a nested
attribute under the CT action. This data is stored with the conntrack
entry, and is executed after the lookup occurs for the CT action. The
conntrack entry itself must be committed using the COMMIT flag in the CT
action flags for this change to persist.

Signed-off-by: Justin Pettit <jpettit@nicira.com>
Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Add conntrack action

Expose the kernel connection tracker via OVS. Userspace components can
make use of the CT action to populate the connection state (ct_state)
field for a flow. This state can be subsequently matched.

Exposed connection states are OVS_CS_F_*:
- NEW (0x01) - Beginning of a new connection.
- ESTABLISHED (0x02) - Part of an existing connection.
- RELATED (0x04) - Related to an established connection.
- INVALID (0x20) - Could not track the connection for this packet.
- REPLY_DIR (0x40) - This packet is in the reply direction for the flow.
- TRACKED (0x80) - This packet has been sent through conntrack.

When the CT action is executed by itself, it will send the packet
through the connection tracker and populate the ct_state field with one
or more of the connection state flags above. The CT action will always
set the TRACKED bit.

When the COMMIT flag is passed to the conntrack action, this specifies
that information about the connection should be stored. This allows
subsequent packets for the same (or related) connections to be
correlated with this connection. Sending subsequent packets for the
connection through conntrack allows the connection tracker to consider
the packets as ESTABLISHED, RELATED, and/or REPLY_DIR.

The CT action may optionally take a zone to track the flow within. This
allows connections with the same 5-tuple to be kept logically separate
from connections in other zones. If the zone is specified, then the
"ct_zone" match field will be subsequently populated with the zone id.

IP fragments are handled by transparently assembling them as part of the
CT action. The maximum received unit (MRU) size is tracked so that
refragmentation can occur during output.

IP frag handling contributed by Andy Zhou.

Based on original design by Justin Pettit.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Justin Pettit <jpettit@nicira.com>
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Move MASKED* macros to datapath.h

This will allow the ovs-conntrack code to reuse these macros.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool

inet_proto_csum_replace4,2,16 take a pseudohdr argument which indicates
the checksum field carries a pseudo header. This argument should be a
boolean instead of an int.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Make 100 percents packets sampled when sampling rate is 1.

When sampling rate is 1, the sampling probability is UINT32_MAX. The packet
should be sampled even the prandom32() generate the number of UINT32_MAX.
And none packet need be sampled when the probability is 0.

Signed-off-by: Wenyu Zhang <wenyuz@vmware.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Fix L4 checksum handling when dealing with IP fragments

openvswitch modifies the L4 checksum of a packet when modifying
the ip address. When an IP packet is fragmented only the first
fragment contains an L4 header and checksum. Prior to this change
openvswitch would modify all fragments, modifying application data
in non-first fragments, causing checksum failures in the
reassembled packet.

Signed-off-by: Glenn Griffin <ggriffin.kernel@gmail.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Make tunnel set action attach a metadata dst

Utilize the new metadata dst to attach encapsulation instructions to
the skb. The existing egress_tun_info via the OVS_CB() is left in
place until all tunnel vports have been converted to the new method.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ip_tunnel: Make ovs_tunnel_info and ovs_key_ipv4_tunnel generic

Rename the tunnel metadata data structures currently internal to
OVS and make them generic for use by all IP tunnels.

Both structures are kernel internal and will stay that way. Their
members are exposed to user space through individual Netlink
attributes by OVS. It will therefore be possible to extend/modify
these structures without affecting user ABI.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: include datapath actions with sampled-packet upcall to userspace

If new optional attribute OVS_USERSPACE_ATTR_ACTIONS is added to an
OVS_ACTION_ATTR_USERSPACE action, then include the datapath actions
in the upcall.

This Directly associates the sampled packet with the path it takes
through the virtual switch. Path information currently includes mangling,
encapsulation and decapsulation actions for tunneling protocols GRE,
VXLAN, Geneve, MPLS and QinQ, but this extension requires no further
changes to accommodate datapath actions that may be added in the
future.

Adding path information enhances visibility into complex virtual
networks.

Signed-off-by: Neil McKee <neil.mckee@inmon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: openvswitch: Support masked set actions.

OVS userspace already probes the openvswitch kernel module for
OVS_ACTION_ATTR_SET_MASKED support. This patch adds the kernel module
implementation of masked set actions.

The existing set action sets many fields at once. When only a subset
of the IP header fields, for example, should be modified, all the IP
fields need to be exact matched so that the other field values can be
copied to the set action. A masked set action allows modification of
an arbitrary subset of the supported header bits without requiring the
rest to be matched.

Masked set action is now supported for all writeable key types, except
for the tunnel key. The set tunnel action is an exception as any
input tunnel info is cleared before action processing starts, so there
is no tunnel info to mask.

The kernel module converts all (non-tunnel) set actions to masked set
actions. This makes action processing more uniform, and results in
less branching and duplicating the action processing code. When
returning actions to userspace, the fully masked set actions are
converted back to normal set actions. We use a kernel internal action
code to be able to tell the userspace provided and converted masked
set actions apart.

Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rename vlan_tx_* helpers since "tx" is misleading there

The same macros are used for rx as well. So rename it.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Fix GSO with multiple MPLS label.

MPLS GSO needs to know inner most protocol to process GSO packets.

Fixes: 25cd9ba0abc ("openvswitch: Add basic MPLS support to
kernel").

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: move vlan pop/push functions into common code

So it can be used from out of openvswitch code.
Did couple of cosmetic changes on the way, namely variable naming and
adding support for 8021AD proto.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: move make_writable helper into common code

note that skb_make_writable already exists in net/netfilter/core.c
but does something slightly different.

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vlan: rename __vlan_put_tag to vlan_insert_tag_set_proto

Name fits better. Plus there's going to be introduced
__vlan_insert_tag later on.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: actions: use skb_postpull_rcsum when possible

Replace duplicated code by calling skb_postpull_rcsum

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Fix checksum calculation when modifying ICMPv6 packets.

The checksum of ICMPv6 packets uses the IP pseudoheader as part of
the calculation, unlike ICMP in IPv4. This was not implemented,
which means that modifying the IP addresses of an ICMPv6 packet
would cause the checksum to no longer be correct as the psuedoheader
did not match.
Introduced by commit 3fdbd1ce11e5 ("openvswitch: add ipv6 'set' action").

Reported-by: Neal Shrader <icosahedral@gmail.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Fix memory leak.

Need to free memory in case of sample action error.

Introduced by commit 651887b0c22cffcfce7eb9c ("openvswitch: Sample
action without side effects").

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Constify various function arguments

Help produce better optimized code.

Signed-off-by: Thomas Graf <tgraf@noironetworks.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Remove redundant key ref from upcall_info.

struct dp_upcall_info has pointer to pkt_key which is already
available in OVS_CB. This also simplifies upcall handling
for gso packet.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Andy Zhou <azhou@nicira.com>

openvswitch: Optimize recirc action.

OVS need to flow key for flow lookup in recic action. OVS
does key extract in recic action. Most of cases we could
use OVS_CB packet key directly and can avoid packet flow key
extract. SET action we can update flow-key along with packet
to keep it consistent. But there are some action like MPLS
pop which forces OVS to do flow-extract. In such cases we
can mark flow key as invalid so that subsequent recirc
action can do full flow extract.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Andy Zhou <azhou@nicira.com>

openvswitch: Extend packet attribute for egress tunnel info

OVS vswitch has extended IPFIX exporter to export tunnel headers
to improve network visibility.
To export this information userspace needs to know egress tunnel
for given packet. By extending packet attributes datapath can
export egress tunnel info for given packet. So that userspace
can ask for egress tunnel info in userspace action. This
information is used to build IPFIX data for given flow.

Signed-off-by: Wenyu Zhang <wenyuz@vmware.com>
Acked-by: Romain Lenglet <rlenglet@vmware.com>
Acked-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Remove flow member from struct ovs_skb_cb

The 'flow' memeber was chosen for removal because it's only used
in ovs_execute_actions() we can pass it as argument to this
function.

Signed-off-by: Lorand Jakab <lojakab@cisco.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: refactor do_output() to move NULL check out of fast path

skb_clone() NULL check is implemented in do_output(), as past of the
common (fast) path. Refactoring so that NULL check is done in the
slow path, immediately after skb_clone() is called.

Besides optimization, this change also improves code readability by
making the skb_clone() NULL check consistent within OVS datapath
module.

Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Add basic MPLS support to kernel

Allow datapath to recognize and extract MPLS labels into flow keys
and execute actions which push, pop, and set labels on packets.

Based heavily on work by Leo Alterman, Ravi K, Isaku Yamahata and Joe Stringer.

Cc: Ravi K <rkerur@gmail.com>
Cc: Leo Alterman <lalterman@nicira.com>
Cc: Isaku Yamahata <yamahata@valinux.co.jp>
Cc: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

datapath: Rename last_action() as nla_is_last() and move to netlink.h

The original motivation for this change was to allow the helper to be used
in files other than actions.c as part of work on an odp select group
action.

It was as pointed out by Thomas Graf that this helper would be best off
living in netlink.h. Furthermore, I think that the generic nature of this
helper means it is best off in netlink.h regardless of if it is used more
than one .c file or not. Thus, I would like it considered independent of
the work on an odp select group action.

Cc: Thomas Graf <tgraf@suug.ch>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Andy Zhou <azhou@nicira.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Thomas Graf <tgraf@noironetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Wrap struct ovs_key_ipv4_tunnel in a new structure.

Currently, the flow information that is matched for tunnels and
the tunnel data passed around with packets is the same. However,
as additional information is added this is not necessarily desirable,
as in the case of pointers.

This adds a new structure for tunnel metadata which currently contains
only the existing struct. This change is purely internal to the kernel
since the current OVS_KEY_ATTR_IPV4_TUNNEL is simply a compressed version
of OVS_KEY_ATTR_TUNNEL that is translated at flow setup.

Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Add recirc and hash action.

Recirc action allows a packet to reenter openvswitch processing.
currently openvswitch lookup flow for packet received and execute
set of actions on that packet, with help of recirc action we can
process/modify the packet and recirculate it back in openvswitch
for another pass.

OVS hash action calculates 5-tupple hash and set hash in flow-key
hash. This can be used along with recirculation for distributing
packets among different ports for bond devices.
For example:
OVS bonding can use following actions:
Match on: bond flow; Action: hash, recirc(id)
Match on: recirc-id == id and hash lower bits == a;
Action: output port_bond_a

Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: simplify sample action implementation

The current sample() function implementation is more complicated
than necessary in handling single user space action optimization
and skb reference counting. There is no functional changes.

Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Use tun_key only for egress tunnel path.

Currently tun_key is used for passing tunnel information
on ingress and egress path, this cause confusion. Following
patch removes its use on ingress path make it egress only parameter.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Andy Zhou <azhou@nicira.com>

openvswitch: Remove pkt_key from OVS_CB

OVS keeps pointer to packet key in skb->cb, but the packet key is
store on stack. This could make code bit tricky. So it is better to
get rid of the pointer.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: fix panic with multiple vlan headers

When there are multiple vlan headers present in a received frame, the first
one is put into vlan_tci and protocol is set to ETH_P_8021Q. Anything in the
skb beyond the VLAN TPID may be still non-linear, including the inner TCI
and ethertype. While ovs_flow_extract takes care of IP and IPv6 headers, it
does nothing with ETH_P_8021Q. Later, if OVS_ACTION_ATTR_POP_VLAN is
executed, __pop_vlan_tci pulls the next vlan header into vlan_tci.

This leads to two things:

1. Part of the resulting ethernet header is in the non-linear part of the
skb. When eth_type_trans is called later as the result of
OVS_ACTION_ATTR_OUTPUT, kernel BUGs in __skb_pull. Also, __pop_vlan_tci
is in fact accessing random data when it reads past the TPID.

2. network_header points into the ethernet header instead of behind it.
mac_len is set to a wrong value (10), too.

Reported-by: Yulong Pei <ypei@redhat.com>
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Add skb_clone NULL check for the sampling action.

Fix a bug where skb_clone() NULL check is missing in sample action
implementation.

Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Sample action without side effects

The sample action is rather generic, allowing arbitrary actions to be
executed based on a probability. However its use, within the Open
vSwitch
code-base is limited: only a single user-space action is ever nested.

A consequence of the current implementation of sample actions is that
depending on weather the sample action executed (due to its probability)
any side-effects of nested actions may or may not be present before
executing subsequent actions. This has the potential to complicate
verification of valid actions by the (kernel) datapath. And indeed
adding support for push and pop MPLS actions inside sample actions
is one case where such case.

In order to allow all supported actions to be continue to be nested
inside sample actions without the potential need for complex
verification code this patch changes the implementation of the sample
action in the kernel datapath so that sample actions are more like
a function call and any side effects of nested actions are not
present when executing subsequent actions.

With the above in mind the motivation for this change is twofold:

* To contain side-effects the sample action in the hope of making it
easier to deal with in the future and;
* To avoid some rather complex verification code introduced in the MPLS
datapath patch.

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Fix a double free bug for the sample action

When sample action returns with an error, the skb has already been
freed. This patch fix a bug to make sure we don't free it again.
This bug introduced by commit ccb1352e76cff05 (net: Add Open vSwitch
kernel components.)

Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>

openvswitch: Use ether_addr_copy

It's slightly smaller/faster for some architectures.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

net: replace macros net_random and net_srandom with direct calls to prandom

This patch removes the net_random and net_srandom macros and replaces
them with direct calls to the prandom ones. As new commits only seem to
use prandom_u32 there is no use to keep them around.
This change makes it easier to grep for users of prandom_u32.

Signed-off-by: Aruna-Hewapathirane <aruna.hewapathirane@gmail.com>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Add utility functions to clear rxhash

In several places 'skb->rxhash = 0' is being done to clear the
rxhash value in an skb. This does not clear l4_rxhash which could
still be set so that the rxhash wouldn't be recalculated on subsequent
call to skb_get_rxhash. This patch adds an explict function to clear
all the rxhash related information in the skb properly.

skb_clear_hash_if_not_l4 clears the rxhash only if it is not marked as
l4_rxhash.

Fixed up places where 'skb->rxhash = 0' was being called.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Add SCTP support

This patch adds support for rewriting SCTP src,dst ports similar to the
functionality already available for TCP/UDP.

Rewriting SCTP ports is expensive due to double-recalculation of the
SCTP checksums; this is performed to ensure that packets traversing OVS
with invalid checksums will continue to the destination with any
checksum corruption intact.

Reviewed-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

openvswitch: Mega flow implementation

Add wildcarded flow support in kernel datapath.

Wildcarded flow can improve OVS flow set up performance by avoid sending
matching new flows to the user space program. The exact performance boost
will largely dependent on wildcarded flow hit rate.

In case all new flows hits wildcard flows, the flow set up rate is
within 5% of that of linux bridge module.

Pravin has made significant contributions to this patch. Including API
clean ups and bug fixes.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

openvswitch: Reset tunnel key between input and output.

It doesn't make sense to output a tunnel packet using the same
parameters that it was received with since that will generally
just result in the packet going back to us. As a result, userspace
assumes that the tunnel key is cleared when transitioning through
the switch. In the majority of cases this doesn't matter since a
packet is either going to a tunnel port (in which the key is
overwritten with new values) or to a non-tunnel port (in which
case the key is ignored). However, it's theoreticaly possible that
userspace could rely on the documented behavior, so this corrects
it.

Signed-off-by: Jesse Gross <jesse@nicira.com>

openvswitch: Add tunneling interface.

Add ovs tunnel interface for set tunnel action for userspace.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: make skb->csum consistent with rest of networking stack.

Following patch keeps skb->csum correct across ovs.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

net: vlan: add protocol argument to packet tagging functions

Add a protocol argument to the VLAN packet tagging functions. In case of HW
tagging, we need that protocol available in the ndo_start_xmit functions,
so it is stored in a new field in the skb. The new field fits into a hole
(on 64 bit) and doesn't increase the sks's size.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: fix the calculation of checksum for vlan header

In vlan_insert_tag(), we insert a 4-byte VLAN header _after_
mac header:

memmove(skb->data, skb->data + VLAN_HLEN, 2 * ETH_ALEN);
...
veth->h_vlan_proto = htons(ETH_P_8021Q);
...
veth->h_vlan_TCI = htons(vlan_tci);

so after it, we should recompute the checksum to include these 4 bytes.
skb->data still points to the mac header, therefore VLAN header is at
(2 * ETH_ALEN = 12) bytes after it, not (ETH_HLEN = 14) bytes.

This can also be observed via tcpdump:

0x0000: ffff ffff ffff 5254 005d 6f6e 8100 000a
0x0010: 0806 0001 0800 0604 0001 5254 005d 6f6e
0x0020: c0a8 026e 0000 0000 0000 c0a8 0282

Similar for __pop_vlan_tci(), the vlan header we remove is the one
overwritten in:

memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN);

Therefore the VLAN_HLEN = 4 bytes after 2 * ETH_ALEN is the part
we want to sub from checksum.

Cc: David S. Miller <davem@davemloft.net>
Cc: Jesse Gross <jesse@nicira.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

openvswitch: add skb mark matching and set action

This patch adds support for skb mark matching and set action.

Signed-off-by: Ansis Atteka <aatteka@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

openvswitch: add ipv6 'set' action

This patch adds ipv6 set action functionality. It allows to change
traffic class, flow label, hop-limit, ipv6 source and destination
address fields.

Signed-off-by: Ansis Atteka <aatteka@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

netlink: Rename pid to portid to avoid confusion

It is a frequent mistake to confuse the netlink port identifier with a
process identifier. Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.

I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.

I have successfully built an allyesconfig kernel with this change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Increase maximum number of datapath ports.

Use hash table to store ports of datapath. Allow 64K ports per switch.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

openvswitch: Fix typo

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Jesse Gross <jesse@nicira.com>

Revert "openvswitch: potential NULL deref in sample()"

This reverts commit 5b3e7e6cb5771bedda51cdb6f715d1da8cd9e644.

The problem that the original commit was attempting to fix can
never happen in practice because validation is done one a per-flow
basis rather than a per-packet basis. Adding additional checks at
runtime is unnecessary and inconsistent with the rest of the code.

CC: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: potential NULL deref in sample()

If there is no OVS_SAMPLE_ATTR_ACTIONS set then "acts_list" is NULL and
it leads to a NULL dereference when we call nla_len(acts_list). This
is a static checker fix, not something I have seen in testing.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Replace Nicira Networks.

Replaced all instances of Nicira Networks(, Inc) to Nicira, Inc.

Signed-off-by: Raju Subramanian <rsubramanian@nicira.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

openvswitch: Fix checksum update for actions on UDP packets.

When modifying IP addresses or ports on a UDP packet we don't
correctly follow the rules for unchecksummed packets. This meant
that packets without a checksum can be given a incorrect new checksum
and packets with a checksum can become marked as being unchecksummed.
This fixes it to handle those requirements.

Signed-off-by: Jesse Gross <jesse@nicira.com>

net: Add Open vSwitch kernel components.

Open vSwitch is a multilayer Ethernet switch targeted at virtualized
environments. In addition to supporting a variety of features
expected in a traditional hardware switch, it enables fine-grained
programmatic extension and flow-based control of the network.
This control is useful in a wide variety of applications but is
particularly important in multi-server virtualization deployments,
which are often characterized by highly dynamic endpoints and the need
to maintain logical abstractions for multiple tenants.

The Open vSwitch datapath provides an in-kernel fast path for packet
forwarding. It is complemented by a userspace daemon, ovs-vswitchd,
which is able to accept configuration from a variety of sources and
translate it into packet processing rules.

See http://openvswitch.org for more information and userspace
utilities.

Signed-off-by: Jesse Gross <jesse@nicira.com>