sctp: handle invalid error codes without calling BUG()

The sctp_sf_eat_auth() function is supposed to return enum sctp_disposition
values but if the call to sctp_ulpevent_make_authkey() fails, it returns
-ENOMEM.

This results in calling BUG() inside the sctp_side_effects() function.
Calling BUG() is an over reaction and not helpful. Call WARN_ON_ONCE()
instead.

This code predates git.

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

sctp: delete the nested flexible array variable

This patch deletes the flexible-array variable[] from the structure
sctp_sackhdr and sctp_errhdr to avoid some sparse warnings:

# make C=2 CF="-Wflexible-array-nested" M=./net/sctp/
net/sctp/sm_statefuns.c: note: in included file (through include/net/sctp/structs.h, include/net/sctp/sctp.h):
./include/linux/sctp.h:451:28: warning: nested flexible array
./include/linux/sctp.h:393:29: warning: nested flexible array

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: check asoc strreset_chunk in sctp_generate_reconf_event

A null pointer reference issue can be triggered when the response of a
stream reconf request arrives after the timer is triggered, such as:

send Incoming SSN Reset Request --->
CPU0:
reconf timer is triggered,
go to the handler code before hold sk lock
<--- reply with Outgoing SSN Reset Request
CPU1:
process Outgoing SSN Reset Request,
and set asoc->strreset_chunk to NULL
CPU0:
continue the handler code, hold sk lock,
and try to hold asoc->strreset_chunk, crash!

In Ying Xu's testing, the call trace is:

[ ] BUG: kernel NULL pointer dereference, address: 0000000000000010
[ ] RIP: 0010:sctp_chunk_hold+0xe/0x40 [sctp]
[ ] Call Trace:
[ ] <IRQ>
[ ] sctp_sf_send_reconf+0x2c/0x100 [sctp]
[ ] sctp_do_sm+0xa4/0x220 [sctp]
[ ] sctp_generate_reconf_event+0xbd/0xe0 [sctp]
[ ] call_timer_fn+0x26/0x130

This patch is to fix it by returning from the timer handler if asoc
strreset_chunk is already set to NULL.

Fixes: 7b9438de0cd4 ("sctp: add stream reconf timer")
Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: add the probe timer in transport for PLPMTUD

There are 3 timers described in rfc8899#section-5.1.1:

PROBE_TIMER, PMTU_RAISE_TIMER, CONFIRMATION_TIMER

This patches adds a 'probe_timer' in transport, and it works as either
PROBE_TIMER or PMTU_RAISE_TIMER. At most time, it works as PROBE_TIMER
and expires every a 'probe_interval' time to send the HB probe packet.
When transport pl enters COMPLETE state, it works as PMTU_RAISE_TIMER
and expires in 'probe_interval * 30' time to go back to SEARCH state
and do searching again.

SCTP HB is an acknowledged packet, CONFIRMATION_TIMER is not needed.

The timer will start when transport pl enters BASE state and stop
when it enters DISABLED state.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: do asoc update earlier in sctp_sf_do_dupcook_b

The same thing should be done for sctp_sf_do_dupcook_b().
Meanwhile, SCTP_CMD_UPDATE_ASSOC cmd can be removed.

v1->v2:
- Fix the return value in sctp_sf_do_assoc_update().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: change to hold/put transport for proto_unreach_timer

A call trace was found in Hangbin's Codenomicon testing with debug kernel:

[ 2615.981988] ODEBUG: free active (active state 0) object type: timer_list hint: sctp_generate_proto_unreach_event+0x0/0x3a0 [sctp]
[ 2615.995050] WARNING: CPU: 17 PID: 0 at lib/debugobjects.c:328 debug_print_object+0x199/0x2b0
[ 2616.095934] RIP: 0010:debug_print_object+0x199/0x2b0
[ 2616.191533] Call Trace:
[ 2616.194265] <IRQ>
[ 2616.202068] debug_check_no_obj_freed+0x25e/0x3f0
[ 2616.207336] slab_free_freelist_hook+0xeb/0x140
[ 2616.220971] kfree+0xd6/0x2c0
[ 2616.224293] rcu_do_batch+0x3bd/0xc70
[ 2616.243096] rcu_core+0x8b9/0xd00
[ 2616.256065] __do_softirq+0x23d/0xacd
[ 2616.260166] irq_exit+0x236/0x2a0
[ 2616.263879] smp_apic_timer_interrupt+0x18d/0x620
[ 2616.269138] apic_timer_interrupt+0xf/0x20
[ 2616.273711] </IRQ>

This is because it holds asoc when transport->proto_unreach_timer starts
and puts asoc when the timer stops, and without holding transport the
transport could be freed when the timer is still running.

So fix it by holding/putting transport instead for proto_unreach_timer
in transport, just like other timers in transport.

v1->v2:
- Also use sctp_transport_put() for the "out_unlock:" path in
sctp_generate_proto_unreach_event(), as Marcelo noticed.

Fixes: 50b5d6ad6382 ("sctp: Fix a race between ICMP protocol unreachable and connect()")
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://lore.kernel.org/r/102788809b554958b13b95d33440f5448113b8d6.1605331373.git.lucien.xin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

sctp: Fix COMM_LOST/CANT_STR_ASSOC err reporting on big-endian platforms

Commit 978aa0474115 ("sctp: fix some type cast warnings introduced since
very beginning")' broke err reading from sctp_arg, because it reads the
value as 32-bit integer, although the value is stored as 16-bit integer.
Later this value is passed to the userspace in 16-bit variable, thus the
user always gets 0 on big-endian platforms. Fix it by reading the __u16
field of sctp_arg union, as reading err field would produce a sparse
warning.

Fixes: 978aa0474115 ("sctp: fix some type cast warnings introduced since very beginning")
Signed-off-by: Petr Malat <oss@malat.biz>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://lore.kernel.org/r/20201030132633.7045-1-oss@malat.biz
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

sctp: Don't add the shutdown timer if its already been added

This BUG halt was reported a while back, but the patch somehow got
missed:

PID: 2879 TASK: c16adaa0 CPU: 1 COMMAND: "sctpn"
#0 [f418dd28] crash_kexec at c04a7d8c
#1 [f418dd7c] oops_end at c0863e02
#2 [f418dd90] do_invalid_op at c040aaca
#3 [f418de28] error_code (via invalid_op) at c08631a5
EAX: f34baac0 EBX: 00000090 ECX: f418deb0 EDX: f5542950 EBP: 00000000
DS: 007b ESI: f34ba800 ES: 007b EDI: f418dea0 GS: 00e0
CS: 0060 EIP: c046fa5e ERR: ffffffff EFLAGS: 00010286
#4 [f418de5c] add_timer at c046fa5e
#5 [f418de68] sctp_do_sm at f8db8c77 [sctp]
#6 [f418df30] sctp_primitive_SHUTDOWN at f8dcc1b5 [sctp]
#7 [f418df48] inet_shutdown at c080baf9
#8 [f418df5c] sys_shutdown at c079eedf
#9 [f418df70] sys_socketcall at c079fe88
EAX: ffffffda EBX: 0000000d ECX: bfceea90 EDX: 0937af98
DS: 007b ESI: 0000000c ES: 007b EDI: b7150ae4
SS: 007b ESP: bfceea7c EBP: bfceeaa8 GS: 0033
CS: 0073 EIP: b775c424 ERR: 00000066 EFLAGS: 00000282

It appears that the side effect that starts the shutdown timer was processed
multiple times, which can happen as multiple paths can trigger it. This of
course leads to the BUG halt in add_timer getting called.

Fix seems pretty straightforward, just check before the timer is added if its
already been started. If it has mod the timer instead to min(current
expiration, new expiration)

Its been tested but not confirmed to fix the problem, as the issue has only
occured in production environments where test kernels are enjoined from being
installed. It appears to be a sane fix to me though. Also, recentely,
Jere found a reproducer posted on list to confirm that this resolves the
issues

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: jere.leppanen@nokia.com
CC: marcelo.leitner@gmail.com
CC: netdev@vger.kernel.org
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: free cmd->obj.chunk for the unprocessed SCTP_CMD_REPLY

This patch is to fix a memleak caused by no place to free cmd->obj.chunk
for the unprocessed SCTP_CMD_REPLY. This issue occurs when failing to
process a cmd while there're still SCTP_CMD_REPLY cmds on the cmd seq
with an allocated chunk in cmd->obj.chunk.

So fix it by freeing cmd->obj.chunk for each SCTP_CMD_REPLY cmd left on
the cmd seq when any cmd returns error. While at it, also remove 'nomem'
label.

Reported-by: syzbot+107c4aff5f392bf1517f@syzkaller.appspotmail.com
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: get netns from asoc and ep base

Commit 312434617cb1 ("sctp: cache netns in sctp_ep_common") set netns
in asoc and ep base since they're created, and it will never change.
It's a better way to get netns from asoc and ep base, comparing to
calling sock_net().

This patch is to replace them.

v1->v2:
- no change.

Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: add support for Primary Path Switchover

This is a new feature defined in section 5 of rfc7829: "Primary Path
Switchover". By introducing a new tunable parameter:

Primary.Switchover.Max.Retrans (PSMR)

The primary path will be changed to another active path when the path
error counter on the old primary path exceeds PSMR, so that "the SCTP
sender is allowed to continue data transmission on a new working path
even when the old primary destination address becomes active again".

This patch is to add this tunable parameter, 'ps_retrans' per netns,
sock, asoc and transport. It also allows a user to change ps_retrans
per netns by sysctl, and ps_retrans per sock/asoc/transport will be
initialized with it.

The check will be done in sctp_do_8_2_transport_strike() when this
feature is enabled.

Note this feature is disabled by initializing 'ps_retrans' per netns
as 0xffff by default, and its value can't be less than 'pf_retrans'
when changing by sysctl.

v3->v4:
- add define SCTP_PS_RETRANS_MAX 0xffff, and use it on extra2 of
sysctl 'ps_retrans'.
- add a new entry for ps_retrans on ip-sysctl.txt.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: use transport pf_retrans in sctp_do_8_2_transport_strike

Transport should use its own pf_retrans to do the error_count
check, instead of asoc's. Otherwise, it's meaningless to make
pf_retrans per transport.

Fixes: 5aa93bcf66f4 ("sctp: Implement quick failover draft from tsvwg")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fix the transport error_count check

As the annotation says in sctp_do_8_2_transport_strike():

"If the transport error count is greater than the pf_retrans
threshold, and less than pathmaxrtx ..."

It should be transport->error_count checked with pathmaxrxt,
instead of asoc->pf_retrans.

Fixes: 5aa93bcf66f4 ("sctp: Implement quick failover draft from tsvwg")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>

Fix memory leak in sctp_process_init

syzbot found the following leak in sctp_process_init
BUG: memory leak
unreferenced object 0xffff88810ef68400 (size 1024):
comm "syz-executor273", pid 7046, jiffies 4294945598 (age 28.770s)
hex dump (first 32 bytes):
1d de 28 8d de 0b 1b e3 b5 c2 f9 68 fd 1a 97 25 ..(........h...%
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000a02cebbd>] kmemleak_alloc_recursive include/linux/kmemleak.h:55
[inline]
[<00000000a02cebbd>] slab_post_alloc_hook mm/slab.h:439 [inline]
[<00000000a02cebbd>] slab_alloc mm/slab.c:3326 [inline]
[<00000000a02cebbd>] __do_kmalloc mm/slab.c:3658 [inline]
[<00000000a02cebbd>] __kmalloc_track_caller+0x15d/0x2c0 mm/slab.c:3675
[<000000009e6245e6>] kmemdup+0x27/0x60 mm/util.c:119
[<00000000dfdc5d2d>] kmemdup include/linux/string.h:432 [inline]
[<00000000dfdc5d2d>] sctp_process_init+0xa7e/0xc20
net/sctp/sm_make_chunk.c:2437
[<00000000b58b62f8>] sctp_cmd_process_init net/sctp/sm_sideeffect.c:682
[inline]
[<00000000b58b62f8>] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1384
[inline]
[<00000000b58b62f8>] sctp_side_effects net/sctp/sm_sideeffect.c:1194
[inline]
[<00000000b58b62f8>] sctp_do_sm+0xbdc/0x1d60 net/sctp/sm_sideeffect.c:1165
[<0000000044e11f96>] sctp_assoc_bh_rcv+0x13c/0x200
net/sctp/associola.c:1074
[<00000000ec43804d>] sctp_inq_push+0x7f/0xb0 net/sctp/inqueue.c:95
[<00000000726aa954>] sctp_backlog_rcv+0x5e/0x2a0 net/sctp/input.c:354
[<00000000d9e249a8>] sk_backlog_rcv include/net/sock.h:950 [inline]
[<00000000d9e249a8>] __release_sock+0xab/0x110 net/core/sock.c:2418
[<00000000acae44fa>] release_sock+0x37/0xd0 net/core/sock.c:2934
[<00000000963cc9ae>] sctp_sendmsg+0x2c0/0x990 net/sctp/socket.c:2122
[<00000000a7fc7565>] inet_sendmsg+0x64/0x120 net/ipv4/af_inet.c:802
[<00000000b732cbd3>] sock_sendmsg_nosec net/socket.c:652 [inline]
[<00000000b732cbd3>] sock_sendmsg+0x54/0x70 net/socket.c:671
[<00000000274c57ab>] ___sys_sendmsg+0x393/0x3c0 net/socket.c:2292
[<000000008252aedb>] __sys_sendmsg+0x80/0xf0 net/socket.c:2330
[<00000000f7bf23d1>] __do_sys_sendmsg net/socket.c:2339 [inline]
[<00000000f7bf23d1>] __se_sys_sendmsg net/socket.c:2337 [inline]
[<00000000f7bf23d1>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2337
[<00000000a8b4131f>] do_syscall_64+0x76/0x1a0 arch/x86/entry/common.c:3

The problem was that the peer.cookie value points to an skb allocated
area on the first pass through this function, at which point it is
overwritten with a heap allocated value, but in certain cases, where a
COOKIE_ECHO chunk is included in the packet, a second pass through
sctp_process_init is made, where the cookie value is re-allocated,
leaking the first allocation.

Fix is to always allocate the cookie value, and free it when we are done
using it.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reported-by: syzbot+f7e9153b037eac9b1df8@syzkaller.appspotmail.com
CC: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: netdev@vger.kernel.org
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104

Based on 1 normalized pattern(s):

this sctp implementation is free software you can redistribute it
and or modify it under the terms of the gnu general public license
as published by the free software foundation either version 2 or at
your option any later version this sctp implementation 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 gnu cc see the file copying if not see
http www gnu org licenses

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 42 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091649.683323110@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sctp: avoid running the sctp state machine recursively

Ying triggered a call trace when doing an asconf testing:

BUG: scheduling while atomic: swapper/12/0/0x10000100
Call Trace:
<IRQ> [<ffffffffa4375904>] dump_stack+0x19/0x1b
[<ffffffffa436fcaf>] __schedule_bug+0x64/0x72
[<ffffffffa437b93a>] __schedule+0x9ba/0xa00
[<ffffffffa3cd5326>] __cond_resched+0x26/0x30
[<ffffffffa437bc4a>] _cond_resched+0x3a/0x50
[<ffffffffa3e22be8>] kmem_cache_alloc_node+0x38/0x200
[<ffffffffa423512d>] __alloc_skb+0x5d/0x2d0
[<ffffffffc0995320>] sctp_packet_transmit+0x610/0xa20 [sctp]
[<ffffffffc098510e>] sctp_outq_flush+0x2ce/0xc00 [sctp]
[<ffffffffc098646c>] sctp_outq_uncork+0x1c/0x20 [sctp]
[<ffffffffc0977338>] sctp_cmd_interpreter.isra.22+0xc8/0x1460 [sctp]
[<ffffffffc0976ad1>] sctp_do_sm+0xe1/0x350 [sctp]
[<ffffffffc099443d>] sctp_primitive_ASCONF+0x3d/0x50 [sctp]
[<ffffffffc0977384>] sctp_cmd_interpreter.isra.22+0x114/0x1460 [sctp]
[<ffffffffc0976ad1>] sctp_do_sm+0xe1/0x350 [sctp]
[<ffffffffc097b3a4>] sctp_assoc_bh_rcv+0xf4/0x1b0 [sctp]
[<ffffffffc09840f1>] sctp_inq_push+0x51/0x70 [sctp]
[<ffffffffc099732b>] sctp_rcv+0xa8b/0xbd0 [sctp]

As it shows, the first sctp_do_sm() running under atomic context (NET_RX
softirq) invoked sctp_primitive_ASCONF() that uses GFP_KERNEL flag later,
and this flag is supposed to be used in non-atomic context only. Besides,
sctp_do_sm() was called recursively, which is not expected.

Vlad tried to fix this recursive call in Commit c0786693404c ("sctp: Fix
oops when sending queued ASCONF chunks") by introducing a new command
SCTP_CMD_SEND_NEXT_ASCONF. But it didn't work as this command is still
used in the first sctp_do_sm() call, and sctp_primitive_ASCONF() will
be called in this command again.

To avoid calling sctp_do_sm() recursively, we send the next queued ASCONF
not by sctp_primitive_ASCONF(), but by sctp_sf_do_prm_asconf() in the 1st
sctp_do_sm() directly.

Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: rename enum sctp_event to sctp_event_type

sctp_event is a structure name defined in RFC for sockopt
SCTP_EVENT. To avoid the conflict, rename it.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: whitespace fixes

Remove blank line at EOF and trailing whitespace.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: add SCTP_AUTH_NO_AUTH type for AUTHENTICATION_EVENT

This patch is to add SCTP_AUTH_NO_AUTH type for AUTHENTICATION_EVENT,
as described in section 6.1.8 of RFC6458.

SCTP_AUTH_NO_AUTH: This report indicates that the peer does not
support SCTP authentication as defined in [RFC4895].

Note that the implementation is quite similar as that of
SCTP_ADAPTATION_INDICATION.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: tracepoint: using sock_set_state tracepoint to trace SCTP state transition

With changes in inet_ files, SCTP state transitions are traced with
inet_sock_set_state tracepoint.
As SCTP state names, i.e. SCTP_SS_CLOSED, SCTP_SS_ESTABLISHED,
have the same value with TCP state names. So the output info still print
the TCP state names, that makes the code easy.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: implement handle_ftsn for sctp_stream_interleave

handle_ftsn is added as a member of sctp_stream_interleave, used to skip
ssn for data or mid for idata, called for SCTP_CMD_PROCESS_FWDTSN cmd.

sctp_handle_iftsn works for ifwdtsn, and sctp_handle_fwdtsn works for
fwdtsn. Note that different from sctp_handle_fwdtsn, sctp_handle_iftsn
could do stream abort pd.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo R. Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: implement report_ftsn for sctp_stream_interleave

report_ftsn is added as a member of sctp_stream_interleave, used to
skip tsn from tsnmap, remove old events from reasm or lobby queue,
and abort pd for data or idata, called for SCTP_CMD_REPORT_FWDTSN
cmd and asoc reset.

sctp_report_iftsn works for ifwdtsn, and sctp_report_fwdtsn works
for fwdtsn. Note that sctp_report_iftsn doesn't do asoc abort_pd,
as stream abort_pd will be done when handling ifwdtsn. But when
ftsn is equal with ftsn, which means asoc reset, asoc abort_pd has
to be done.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo R. Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: implement abort_pd for sctp_stream_interleave

abort_pd is added as a member of sctp_stream_interleave, used to abort
partial delivery for data or idata, called in sctp_cmd_assoc_failed.

Since stream interleave allows to do partial delivery for each stream
at the same time, sctp_intl_abort_pd for idata would be very different
from the old function sctp_ulpq_abort_pd for data.

Note that sctp_ulpevent_make_pdapi will support per stream in this
patch by adding pdapi_stream and pdapi_seq in sctp_pdapi_event, as
described in section 6.1.7 of RFC6458.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: implement start_pd for sctp_stream_interleave

start_pd is added as a member of sctp_stream_interleave, used to
do partial_delivery for data or idata when datalen >= asoc->rwnd
in sctp_eat_data. The codes have been done in last patches, but
they need to be extracted into start_pd, so that it could be used
for SCTP_CMD_PART_DELIVER cmd as well.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: implement renege_events for sctp_stream_interleave

renege_events is added as a member of sctp_stream_interleave, used to
renege some old data or idata in reasm or lobby queue properly to free
some memory for the new data when there's memory stress.

It defines sctp_renege_events for idata, and leaves sctp_ulpq_renege
as it is for data.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: implement enqueue_event for sctp_stream_interleave

enqueue_event is added as a member of sctp_stream_interleave, used to
enqueue either data, idata or notification events into user socket rx
queue.

It replaces sctp_ulpq_tail_event used in the other places with
enqueue_event.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: implement ulpevent_data for sctp_stream_interleave

ulpevent_data is added as a member of sctp_stream_interleave, used to
do the most process in ulpq, including to convert data or idata chunk
to event, reasm them in reasm queue and put them in lobby queue in
right order, and deliver them up to user sk rx queue.

This procedure is described in section 2.2.3 of RFC8260.

It adds most functions for idata here to do the similar process as
the old functions for data. But since the details are very different
between them, the old functions can not be reused for idata.

event->ssn and event->ppid settings are moved to ulpevent_data from
sctp_ulpevent_make_rcvmsg, so that sctp_ulpevent_make_rcvmsg could
work for both data and idata.

Note that mid is added in sctp_ulpevent for idata, __packed has to
be used for defining sctp_ulpevent, or it would exceeds the skb cb
that saves a sctp_ulpevent variable for ulp layer process.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fix some type cast warnings introduced since very beginning

These warnings were found by running 'make C=2 M=net/sctp/'.
They are there since very beginning.

Note after this patch, there still one warning left in
sctp_outq_flush():
sctp_chunk_fail(chunk, SCTP_ERROR_INV_STRM)

Since it has been moved to sctp_stream_outq_migrate on net-next,
to avoid the extra job when merging net-next to net, I will post
the fix for it after the merging is done.

Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fix a type cast warnings that causes a_rwnd gets the wrong value

These warnings were found by running 'make C=2 M=net/sctp/'.

Commit d4d6fb5787a6 ("sctp: Try not to change a_rwnd when faking a
SACK from SHUTDOWN.") expected to use the peers old rwnd and add
our flight size to the a_rwnd. But with the wrong Endian, it may
not work as well as expected.

So fix it by converting to the right value.

Fixes: d4d6fb5787a6 ("sctp: Try not to change a_rwnd when faking a SACK from SHUTDOWN.")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-sctp@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: introduce stream scheduler foundations

This patch introduces the hooks necessary to do stream scheduling, as
per RFC Draft ndata. It also introduces the first scheduler, which is
what we do today but now factored out: first come first served (FCFS).

With stream scheduling now we have to track which chunk was enqueued on
which stream and be able to select another other than the in front of
the main outqueue. So we introduce a list on sctp_stream_out_ext
structure for this purpose.

We reuse sctp_chunk->transmitted_list space for the list above, as the
chunk cannot belong to the two lists at the same time. By using the
union in there, we can have distinct names for these moments.

sctp_sched_ops are the operations expected to be implemented by each
scheduler. The dequeueing is a bit particular to this implementation but
it is to match how we dequeue packets today. We first dequeue and then
check if it fits the packet and if not, we requeue it at head. Thus why
we don't have a peek operation but have dequeue_done instead, which is
called once the chunk can be safely considered as transmitted.

The check removed from sctp_outq_flush is now performed by
sctp_stream_outq_migrate, which is only called during assoc setup.
(sctp_sendmsg() also checks for it)

The only operation that is foreseen but not yet added here is a way to
signalize that a new packet is starting or that the packet is done, for
round robin scheduler per packet, but is intentionally left to the
patch that actually implements it.

Support for I-DATA chunks, also described in this RFC, with user message
interleaving is straightforward as it just requires the schedulers to
probe for the feature and ignore datamsg boundaries when dequeueing.

See-also: https://tools.ietf.org/html/draft-ietf-tsvwg-sctp-ndata-13
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_disposition_t

This patch is to remove the typedef sctp_disposition_t, and
replace with enum sctp_disposition in the places where it's
using this typedef.

It's also to fix the indent for many functions' defination.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_sm_table_entry_t

This patch is to remove the typedef sctp_sm_table_entry_t, and
replace with struct sctp_sm_table_entry in the places where it's
using this typedef.

It is also to fix some indents.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_cmd_seq_t

This patch is to remove the typedef sctp_cmd_seq_t, and
replace with struct sctp_cmd_seq in the places where it's
using this typedef.

Note that it doesn't fix many indents although it should,
as sctp_disposition_t's removal would mess them up again.
So better to fix them when removing sctp_disposition_t in
the later patch.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_cmd_t

This patch is to remove the typedef sctp_cmd_t, and
replace with enum sctp_cmd in the places where it's
using this typedef.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_sender_hb_info_t

This patch is to remove the typedef sctp_sender_hb_info_t, and
replace with struct sctp_sender_hb_info in the places where it's
using this typedef.

It is also to use sizeof(variable) instead of sizeof(type).

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_subtype_t

This patch is to remove the typedef sctp_subtype_t, and
replace with union sctp_subtype in the places where it's
using this typedef.

Note that it doesn't fix many indents although it should,
as sctp_disposition_t's removal would mess them up again.
So better to fix them when removing sctp_disposition_t in
later patch.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_event_t

This patch is to remove the typedef sctp_event_t, and
replace with enum sctp_event in the places where it's
using this typedef.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_event_timeout_t

This patch is to remove the typedef sctp_event_timeout_t, and
replace with enum sctp_event_timeout in the places where it's
using this typedef.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_state_t

This patch is to remove the typedef sctp_state_t, and
replace with enum sctp_state in the places where it's
using this typedef.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_errhdr_t

This patch is to remove the typedef sctp_errhdr_t, and replace
with struct sctp_errhdr in the places where it's using this
typedef.

It is also to use sizeof(variable) instead of sizeof(type).

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_init_chunk_t

This patch is to remove the typedef sctp_init_chunk_t, and replace
with struct sctp_init_chunk in the places where it's using this
typedef.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the typedef sctp_chunkhdr_t

This patch is to remove the typedef sctp_chunkhdr_t, and replace
with struct sctp_chunkhdr in the places where it's using this
typedef.

It is also to fix some indents and use sizeof(variable) instead
of sizeof(type)., especially in sctp_new.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: handle errors when updating asoc

It's a bad thing not to handle errors when updating asoc. The memory
allocation failure in any of the functions called in sctp_assoc_update()
would cause sctp to work unexpectedly.

This patch is to fix it by aborting the asoc and reporting the error when
any of these functions fails.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: uncork the old asoc before changing to the new one

local_cork is used to decide if it should uncork asoc outq after processing
some cmds, and it is set when replying or sending msgs. local_cork should
always have the same value with current asoc q->cork in some way.

The thing is when changing to a new asoc by cmd SET_ASOC, local_cork may
not be consistent with the current asoc any more. The cmd seqs can be:

SCTP_CMD_UPDATE_ASSOC (asoc)
SCTP_CMD_REPLY (asoc)
SCTP_CMD_SET_ASOC (new_asoc)
SCTP_CMD_DELETE_TCB (new_asoc)
SCTP_CMD_SET_ASOC (asoc)
SCTP_CMD_REPLY (asoc)

The 1st REPLY makes OLD asoc q->cork and local_cork both are 1, and the cmd
DELETE_TCB clears NEW asoc q->cork and local_cork. After asoc goes back to
OLD asoc, q->cork is still 1 while local_cork is 0. The 2nd REPLY will not
set local_cork because q->cork is already set and it can't be uncorked and
sent out because of this.

To keep local_cork consistent with the current asoc q->cork, this patch is
to uncork the old asoc if local_cork is set before changing to the new one.

Note that the above cmd seqs will be used in the next patch when updating
asoc and handling errors in it.

Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: flush out queue once assoc state falls into SHUTDOWN_PENDING

This patch is to flush out queue when assoc state falls into
SHUTDOWN_PENDING if there are still chunks in it, so that the
data can be sent out as soon as possible before sending SHUTDOWN
chunk.

When sctp supports MSG_MORE flag in next patch, this improvement
can also solve the problem that the chunks with MSG_MORE flag
may be stuck in queue when closing an assoc.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: add dst_pending_confirm flag

Add new transport flag to allow sockets to confirm neighbour.
When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.
The flag is propagated from transport to every packet.
It is reset when cached dst is reset.

Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 5110effee8fd ("net: Do delayed neigh confirmation.")
Fixes: f2bb4bedf35d ("ipv4: Cache output routes in fib_info nexthops.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: add stream reconf timer

This patch is to add a per transport timer based on sctp timer frame
for stream reconf chunk retransmission. It would start after sending
a reconf request chunk, and stop after receiving the response chunk.

If the timer expires, besides retransmitting the reconf request chunk,
it would also do the same thing with data RTO timer. like to increase
the appropriate error counts, and perform threshold management, possibly
destroying the asoc if sctp retransmission thresholds are exceeded, just
as section 5.1.1 describes.

This patch is also to add asoc strreset_chunk, it is used to save the
reconf request chunk, so that it can be retransmitted, and to check if
the response is really for this request by comparing the information
inside with the response chunk as well.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: make sctp_outq_flush/tail/uncork return void

sctp_outq_flush return value is meaningless now, this patch is
to make sctp_outq_flush return void, as well as sctp_outq_fail
and sctp_outq_uncork.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: do not return the transmit err back to sctp_sendmsg

Once a chunk is enqueued successfully, sctp queues can take care of it.
Even if it is failed to transmit (like because of nomem), it should be
put into retransmit queue.

If sctp report this error to users, it confuses them, they may resend
that msg, but actually in kernel sctp stack is in charge of retransmit
it already.

Besides, this error probably is not from the failure of transmitting
current msg, but transmitting or retransmitting another msg's chunks,
as sctp_outq_flush just tries to send out all transports' chunks.

This patch is to make sctp_cmd_send_msg return avoid, and not return the
transmit err back to sctp_sendmsg

Fixes: 8b570dc9f7b6 ("sctp: only drop the reference on the datamsg after sending a msg")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: sctp should change socket state when shutdown is received

Now sctp doesn't change socket state upon shutdown reception. It changes
just the assoc state, even though it's a TCP-style socket.

For some cases, if we really need to check sk->sk_state, it's necessary to
fix this issue, at least when we use ss or netstat to dump, we can get a
more exact information.

As an improvement, we will change sk->sk_state when we change asoc->state
to SHUTDOWN_RECEIVED, and also do it in sctp_shutdown to keep consistent
with sctp_close.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo R. Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: signal sk_data_ready earlier on data chunks reception

Dave Miller pointed out that fb586f25300f ("sctp: delay calls to
sk_data_ready() as much as possible") may insert latency specially if
the receiving application is running on another CPU and that it would be
better if we signalled as early as possible.

This patch thus basically inverts the logic on fb586f25300f and signals
it as early as possible, similar to what we had before.

Fixes: fb586f25300f ("sctp: delay calls to sk_data_ready() as much as possible")
Reported-by: Dave Miller <davem@davemloft.net>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: delay calls to sk_data_ready() as much as possible

Currently processing of multiple chunks in a single SCTP packet leads to
multiple calls to sk_data_ready, causing multiple wake up signals which
are costy and doesn't make it wake up any faster.

With this patch it will note that the wake up is pending and will do it
before leaving the state machine interpreter, latest place possible to
do it realiably and cleanly.

Note that sk_data_ready events are not dependent on asocs, unlike waking
up writers.

v2: series re-checked
v3: use local vars to cleanup the code, suggested by Jakub Sitnicki
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: avoid refreshing heartbeat timer too often

Currently on high rate SCTP streams the heartbeat timer refresh can
consume quite a lot of resources as timer updates are costly and it
contains a random factor, which a) is also costly and b) invalidates
mod_timer() optimization for not editing a timer to the same value.
It may even cause the timer to be slightly advanced, for no good reason.

As suggested by David Laight this patch now removes this timer update
from hot path by leaving the timer on and re-evaluating upon its
expiration if the heartbeat is still needed or not, similarly to what is
done for TCP. If it's not needed anymore the timer is re-scheduled to
the new timeout, considering the time already elapsed.

For this, we now record the last tx timestamp per transport, updated in
the same spots as hb timer was restarted on tx. Also split up
sctp_transport_reset_timers into sctp_transport_reset_t3_rtx and
sctp_transport_reset_hb_timer, so we can re-arm T3 without re-arming the
heartbeat one.

On loopback with MTU of 65535 and data chunks with 1636, so that we
have a considerable amount of chunks without stressing system calls,
netperf -t SCTP_STREAM -l 30, perf looked like this before:

Samples: 103K of event 'cpu-clock', Event count (approx.): 25833000000
Overhead Command Shared Object Symbol
+ 6,15% netperf [kernel.vmlinux] [k] copy_user_enhanced_fast_string
- 5,43% netperf [kernel.vmlinux] [k] _raw_write_unlock_irqrestore
- _raw_write_unlock_irqrestore
- 96,54% _raw_spin_unlock_irqrestore
- 36,14% mod_timer
+ 97,24% sctp_transport_reset_timers
+ 2,76% sctp_do_sm
+ 33,65% __wake_up_sync_key
+ 28,77% sctp_ulpq_tail_event
+ 1,40% del_timer
- 1,84% mod_timer
+ 99,03% sctp_transport_reset_timers
+ 0,97% sctp_do_sm
+ 1,50% sctp_ulpq_tail_event

And after this patch, now with netperf -l 60:

Samples: 230K of event 'cpu-clock', Event count (approx.): 57707250000
Overhead Command Shared Object Symbol
+ 5,65% netperf [kernel.vmlinux] [k] memcpy_erms
+ 5,59% netperf [kernel.vmlinux] [k] copy_user_enhanced_fast_string
- 5,05% netperf [kernel.vmlinux] [k] _raw_spin_unlock_irqrestore
- _raw_spin_unlock_irqrestore
+ 49,89% __wake_up_sync_key
+ 45,68% sctp_ulpq_tail_event
- 2,85% mod_timer
+ 76,51% sctp_transport_reset_t3_rtx
+ 23,49% sctp_do_sm
+ 1,55% del_timer
+ 2,50% netperf [sctp] [k] sctp_datamsg_from_user
+ 2,26% netperf [sctp] [k] sctp_sendmsg

Throughput-wise, from 6800mbps without the patch to 7050mbps with it,
~3.7%.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: do not update a_rwnd if we are not issuing a sack

The SACK can be lost pretty much elsewhere, but if its allocation fail,
we know we are not sending it, so it is better to revert a_rwnd to its
previous value as this may give it a chance to issue a window update
later.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: allow sctp_transmit_packet and others to use gfp

Currently sctp_sendmsg() triggers some calls that will allocate memory
with GFP_ATOMIC even when not necessary. In the case of
sctp_packet_transmit it will allocate a linear skb that will be used to
construct the packet and this may cause sends to fail due to ENOMEM more
often than anticipated specially with big MTUs.

This patch thus allows it to inherit gfp flags from upper calls so that
it can use GFP_KERNEL if it was triggered by a sctp_sendmsg call or
similar. All others, like retransmits or flushes started from BH, are
still allocated using GFP_ATOMIC.

In netperf tests this didn't result in any performance drawbacks when
memory is not too fragmented and made it trigger ENOMEM way less often.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove the dead field of sctp_transport

After we use refcnt to check if transport is alive, the dead can be
removed from sctp_transport.

The traversal of transport_addr_list in procfs dump is using
list_for_each_entry_rcu, no need to check if it has been freed.

sctp_generate_t3_rtx_event and sctp_generate_heartbeat_event is
protected by sock lock, it's not necessary to check dead, either.
also, the timers are cancelled when sctp_transport_free() is
called, that it doesn't wait for refcnt to reach 0 to cancel them.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fix use-after-free in pr_debug statement

Dmitry Vyukov reported a use-after-free in the code expanded by the
macro debug_post_sfx, which is caused by the use of the asoc pointer
after it was freed within sctp_side_effect() scope.

This patch fixes it by allowing sctp_side_effect to clear that asoc
pointer when the TCB is freed.

As Vlad explained, we also have to cover the SCTP_DISPOSITION_ABORT case
because it will trigger DELETE_TCB too on that same loop.

Also, there were places issuing SCTP_CMD_INIT_FAILED and ASSOC_FAILED
but returning SCTP_DISPOSITION_CONSUME, which would fool the scheme
above. Fix it by returning SCTP_DISPOSITION_ABORT instead.

The macro is already prepared to handle such NULL pointer.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: drop the old assoc hashtable of sctp

transport hashtable will replace the association hashtable,
so association hashtable is not used in sctp any more, so
drop the codes about that.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: dynamically enable or disable pf state

As we all know, the value of pf_retrans >= max_retrans_path can
disable pf state. The variables of pf_retrans and max_retrans_path
can be changed by the userspace application.

Sometimes the user expects to disable pf state while the 2
variables are changed to enable pf state. So it is necessary to
introduce a new variable to disable pf state.

According to the suggestions from Vlad Yasevich, extra1 and extra2
are removed. The initialization of pf_enable is added.

Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Prevent soft lockup when sctp_accept() is called during a timeout event

A case can occur when sctp_accept() is called by the user during
a heartbeat timeout event after the 4-way handshake. Since
sctp_assoc_migrate() changes both assoc->base.sk and assoc->ep, the
bh_sock_lock in sctp_generate_heartbeat_event() will be taken with
the listening socket but released with the new association socket.
The result is a deadlock on any future attempts to take the listening
socket lock.

Note that this race can occur with other SCTP timeouts that take
the bh_lock_sock() in the event sctp_accept() is called.

BUG: soft lockup - CPU#9 stuck for 67s! [swapper:0]
...
RIP: 0010:[<ffffffff8152d48e>] [<ffffffff8152d48e>] _spin_lock+0x1e/0x30
RSP: 0018:ffff880028323b20 EFLAGS: 00000206
RAX: 0000000000000002 RBX: ffff880028323b20 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff880028323be0 RDI: ffff8804632c4b48
RBP: ffffffff8100bb93 R08: 0000000000000000 R09: 0000000000000000
R10: ffff880610662280 R11: 0000000000000100 R12: ffff880028323aa0
R13: ffff8804383c3880 R14: ffff880028323a90 R15: ffffffff81534225
FS: 0000000000000000(0000) GS:ffff880028320000(0000) knlGS:0000000000000000
CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 00000000006df528 CR3: 0000000001a85000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process swapper (pid: 0, threadinfo ffff880616b70000, task ffff880616b6cab0)
Stack:
ffff880028323c40 ffffffffa01c2582 ffff880614cfb020 0000000000000000
<d> 0100000000000000 00000014383a6c44 ffff8804383c3880 ffff880614e93c00
<d> ffff880614e93c00 0000000000000000 ffff8804632c4b00 ffff8804383c38b8
Call Trace:
<IRQ>
[<ffffffffa01c2582>] ? sctp_rcv+0x492/0xa10 [sctp]
[<ffffffff8148c559>] ? nf_iterate+0x69/0xb0
[<ffffffff814974a0>] ? ip_local_deliver_finish+0x0/0x2d0
[<ffffffff8148c716>] ? nf_hook_slow+0x76/0x120
[<ffffffff814974a0>] ? ip_local_deliver_finish+0x0/0x2d0
[<ffffffff8149757d>] ? ip_local_deliver_finish+0xdd/0x2d0
[<ffffffff81497808>] ? ip_local_deliver+0x98/0xa0
[<ffffffff81496ccd>] ? ip_rcv_finish+0x12d/0x440
[<ffffffff81497255>] ? ip_rcv+0x275/0x350
[<ffffffff8145cfeb>] ? __netif_receive_skb+0x4ab/0x750
...

With lockdep debugging:

=====================================
[ BUG: bad unlock balance detected! ]
-------------------------------------
CslRx/12087 is trying to release lock (slock-AF_INET) at:
[<ffffffffa01bcae0>] sctp_generate_timeout_event+0x40/0xe0 [sctp]
but there are no more locks to release!

other info that might help us debug this:
2 locks held by CslRx/12087:
#0: (&asoc->timers[i]){+.-...}, at: [<ffffffff8108ce1f>] run_timer_softirq+0x16f/0x3e0
#1: (slock-AF_INET){+.-...}, at: [<ffffffffa01bcac3>] sctp_generate_timeout_event+0x23/0xe0 [sctp]

Ensure the socket taken is also the same one that is released by
saving a copy of the socket before entering the timeout event
critical section.

Signed-off-by: Karl Heiss <kheiss@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Whitespace fix

Fix indentation in sctp_generate_heartbeat_event.

Signed-off-by: Karl Heiss <kheiss@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Do not try to search for the transport twice

When removing an non-primary transport during ASCONF
processing, we end up traversing the transport list
twice: once in sctp_cmd_del_non_primary, and once in
sctp_assoc_del_peer. We can avoid the second
search and call sctp_assoc_rm_peer() instead.
Found by code inspection during code reviews.

Signed-off-by: Vladislav Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: donot reset the overall_error_count in SHUTDOWN_RECEIVE state

Commit f8d960524328 ("sctp: Enforce retransmission limit during shutdown")
fixed a problem with excessive retransmissions in the SHUTDOWN_PENDING by not
resetting the association overall_error_count. This allowed the association
to better enforce assoc.max_retrans limit.

However, the same issue still exists when the association is in SHUTDOWN_RECEIVED
state. In this state, HB-ACKs will continue to reset the overall_error_count
for the association would extend the lifetime of association unnecessarily.

This patch solves this by resetting the overall_error_count whenever the current
state is small then SCTP_STATE_SHUTDOWN_PENDING. As a small side-effect, we
end up also handling SCTP_STATE_SHUTDOWN_ACK_SENT and SCTP_STATE_SHUTDOWN_SENT
states, but they are not really impacted because we disable Heartbeats in those
states.

Fixes: Commit f8d960524328 ("sctp: Enforce retransmission limit during shutdown")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: Don't transition to PF state when transport has exhausted 'Path.Max.Retrans'.

Don't transition to the PF state on every strike after 'Path.Max.Retrans'.
Per draft-ietf-tsvwg-sctp-failover-03 Section 5.1.6:

Additional (PMR - PFMR) consecutive timeouts on a PF destination
confirm the path failure, upon which the destination transitions to the
Inactive state. As described in [RFC4960], the sender (i) SHOULD notify
ULP about this state transition, and (ii) transmit heartbeats to the
Inactive destination at a lower frequency as described in Section 8.3 of
[RFC4960].

This also prevents sending SCTP_ADDR_UNREACHABLE to the user as the state
bounces between SCTP_INACTIVE and SCTP_PF for each subsequent strike.

Signed-off-by: Karl Heiss <kheiss@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: Potentially-Failed state should not be reached from unconfirmed state

In current implementation it is possible to reach PF state from unconfirmed.
We can interpret sctp-failover-02 in a way that PF state is meant to be reached
only from active state, in the end, this is when entering PF state makes sense.
Here are few quotes from sctp-failover-02, but regardless of these, same
understanding can be reached from whole section 5:

Section 5.1, quickfailover guide:
"The PF state is an intermediate state between Active and Failed states."

"Each time the T3-rtx timer expires on an active or idle
destination, the error counter of that destination address will
be incremented. When the value in the error counter exceeds
PFMR, the endpoint should mark the destination transport address as PF."

There are several concrete reasons for such interpretation. For start, rfc4960
does not take into concern quickfailover algorithm. Therefore, quickfailover
must comply to 4960. Point where this compliance can be argued is following
behavior:
When PF is entered, association overall error counter is incremented for each
missed HB. This is contradictory to rfc4960, as address, while in unconfirmed
state, is subjected to probing, and while it is probed, it should not increment
association overall error counter. This has as a consequence that we might end
up in situation in which we drop association due path failure on unconfirmed
address, in case we have wrong configuration in a way:
Association.Max.Retrans == Path.Max.Retrans.

Another reason is that entering PF from unconfirmed will cause a loss of address
confirmed event when address is once (if) confirmed. This is fine from failover
guide point of view, but it is not consistent with behavior preceding failover
implementation and recommendation from 4960:

5.4. Path Verification
Whenever a path is confirmed, an indication MAY be given to the upper
layer.

Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nsn.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove macros sctp_bh_[un]lock_sock

Redefined bh_[un]lock_sock to sctp_bh[un]lock_sock for user
space friendly code which we haven't use in years, so removing them.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fix checkpatch errors with space required or prohibited

fix checkpatch errors while the space is required or prohibited
to the "=,()++..."

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: remove casting from function calls through ops structure

remove the unnecessary cast.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Fix FSF address in file headers

Several files refer to an old address for the Free Software Foundation
in the file header comment. Resolve by replacing the address with
the URL <http://www.gnu.org/licenses/> so that we do not have to keep
updating the header comments anytime the address changes.

CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: do not trigger BUG_ON in sctp_cmd_delete_tcb

Introduced in f9e42b853523 ("net: sctp: sideeffect: throw BUG if
primary_path is NULL"), we intended to find a buggy assoc that's
part of the assoc hash table with a primary_path that is NULL.
However, we better remove the BUG_ON for now and find a more
suitable place to assert for these things as Mark reports that
this also triggers the bug when duplication cookie processing
happens, and the assoc is not part of the hash table (so all
good in this case). Such a situation can for example easily be
reproduced by:

tc qdisc add dev eth0 root handle 1: prio bands 2 priomap 1 1 1 1 1 1
tc qdisc add dev eth0 parent 1:2 handle 20: netem loss 20%
tc filter add dev eth0 protocol ip parent 1: prio 2 u32 match ip \
protocol 132 0xff match u8 0x0b 0xff at 32 flowid 1:2

This drops 20% of COOKIE-ACK packets. After some follow-up
discussion with Vlad we came to the conclusion that for now we
should still better remove this BUG_ON() assertion, and come up
with two follow-ups later on, that is, i) find a more suitable
place for this assertion, and possibly ii) have a special
allocator/initializer for such kind of temporary assocs.

Reported-by: Mark Thomas <Mark.Thomas@metaswitch.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: trivial: update bug report in header comment

With the restructuring of the lksctp.org site, we only allow bug
reports through the SCTP mailing list linux-sctp@vger.kernel.org,
not via SF, as SF is only used for web hosting and nothing more.
While at it, also remove the obvious statement that bugs will be
fixed and incooperated into the kernel.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: trivial: update mailing list address

The SCTP mailing list address to send patches or questions
to is linux-sctp@vger.kernel.org and not
lksctp-developers@lists.sourceforge.net anymore. Therefore,
update all occurences.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: confirm route during forward progress

This fix has been proposed originally by Vlad Yasevich. He says:

When SCTP makes forward progress (receives a SACK that acks new chunks,
renegs, or answeres 0-window probes) or when HB-ACK arrives, mark
the route as confirmed so we don't unnecessarily send NUD probes.

Having a simple SCTP client/server that exchange data chunks every 1sec,
without this patch ARP requests are sent periodically every 40-60sec.
With this fix applied, an ARP request is only done once right at the
"session" beginning. Also, when clearing the related ARP cache entry
manually during the session, a new request is correctly done. I have
only "backported" this to net-next and tested that it works, so full
credit goes to Vlad.

Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: rework debugging framework to use pr_debug and friends

We should get rid of all own SCTP debug printk macros and use the ones
that the kernel offers anyway instead. This makes the code more readable
and conform to the kernel code, and offers all the features of dynamic
debbuging that pr_debug() et al has, such as only turning on/off portions
of debug messages at runtime through debugfs. The runtime cost of having
CONFIG_DYNAMIC_DEBUG enabled, but none of the debug statements printing,
is negligible [1]. If kernel debugging is completly turned off, then these
statements will also compile into "empty" functions.

While we're at it, we also need to change the Kconfig option as it /now/
only refers to the ifdef'ed code portions in outqueue.c that enable further
debugging/tracing of SCTP transaction fields. Also, since SCTP_ASSERT code
was enabled with this Kconfig option and has now been removed, we
transform those code parts into WARNs resp. where appropriate BUG_ONs so
that those bugs can be more easily detected as probably not many people
have SCTP debugging permanently turned on.

To turn on all SCTP debugging, the following steps are needed:

# mount -t debugfs none /sys/kernel/debug
# echo -n 'module sctp +p' > /sys/kernel/debug/dynamic_debug/control

This can be done more fine-grained on a per file, per line basis and others
as described in [2].

[1] https://www.kernel.org/doc/ols/2009/ols2009-pages-39-46.pdf
[2] Documentation/dynamic-debug-howto.txt

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sctp: sideeffect: throw BUG if primary_path is NULL

This clearly states a BUG somewhere in the SCTP code as e.g. fixed once
in f28156335 ("sctp: Use correct sideffect command in duplicate cookie
handling"). If this ever happens, throw a trace in the sideeffect engine
where assocs clearly must have a primary_path assigned.

When in sctp_seq_dump_local_addrs() also throw a WARN and bail out since
we do not need to panic for printing this one asterisk. Also, it will
avoid the not so obvious case when primary != NULL test passes and at a
later point in time triggering a NULL ptr dereference caused by primary.
While at it, also fix up the white space.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: remove redundant check for timer pending state before del_timer

As in del_timer() there has already placed a timer_pending() function
to check whether the timer to be deleted is pending or not, it's
unnecessary to check timer pending state again before del_timer() is
called.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Add support to per-association statistics via a new SCTP_GET_ASSOC_STATS call

The current SCTP stack is lacking a mechanism to have per association
statistics. This is an implementation modeled after OpenSolaris'
SCTP_GET_ASSOC_STATS.

Userspace part will follow on lksctp if/when there is a general ACK on
this.
V4:
- Move ipackets++ before q->immediate.func() for consistency reasons
- Move sctp_max_rto() at the end of sctp_transport_update_rto() to avoid
returning bogus RTO values
- return asoc->rto_min when max_obs_rto value has not changed

V3:
- Increase ictrlchunks in sctp_assoc_bh_rcv() as well
- Move ipackets++ to sctp_inq_push()
- return 0 when no rto updates took place since the last call

V2:
- Implement partial retrieval of stat struct to cope for future expansion
- Kill the rtxpackets counter as it cannot be precise anyway
- Rename outseqtsns to outofseqtsns to make it clearer that these are out
of sequence unexpected TSNs
- Move asoc->ipackets++ under a lock to avoid potential miscounts
- Fold asoc->opackets++ into the already existing asoc check
- Kill unneeded (q->asoc) test when increasing rtxchunks
- Do not count octrlchunks if sending failed (SCTP_XMIT_OK != 0)
- Don't count SHUTDOWNs as SACKs
- Move SCTP_GET_ASSOC_STATS to the private space API
- Adjust the len check in sctp_getsockopt_assoc_stats() to allow for
future struct growth
- Move association statistics in their own struct
- Update idupchunks when we send a SACK with dup TSNs
- return min_rto in max_rto when RTO has not changed. Also return the
transport when max_rto last changed.

Signed-off: Michele Baldessari <michele@acksyn.org>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>

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

sctp: send abort chunk when max_retrans exceeded

In the event that an association exceeds its max_retrans attempts, we should
send an ABORT chunk indicating that we are closing the assocation as a result.
Because of the nature of the error, its unlikely to be received, but its a nice
clean way to close the association if it does make it through, and it will give
anyone watching via tcpdump a clue as to what happened.

Change notes:
v2)
* Removed erroneous changes from sctp_make_violation_parmlen

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Clean up type-punning in sctp_cmd_t union

Lots of points in the sctp_cmd_interpreter function treat the sctp_cmd_t arg as
a void pointer, even though they are written as various other types. Theres no
need for this as doing so just leads to possible type-punning issues that could
cause crashes, and if we remain type-consistent we can actually just remove the
void * member of the union entirely.

Change Notes:

v2)
* Dropped chunk that modified SCTP_NULL to create a marker pattern
should anyone try to use a SCTP_NULL() assigned sctp_arg_t, Assigning
to .zero provides the same effect and should be faster, per Vlad Y.

v3)
* Reverted part of V2, opting to use memset instead of .zero, so that
the entire union is initalized thus avoiding the i164 speculative load
problems previously encountered, per Dave M.. Also rewrote
SCTP_[NO]FORCE so as to use common infrastructure a little more

Signed-off-by: Neil Horman <nhorman@tuxdriver.com
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fix call to SCTP_CMD_PROCESS_SACK in sctp_cmd_interpreter()

Bug introduced by commit edfee0339e681a784ebacec7e8c2dc97dc6d2839
(sctp: check src addr when processing SACK to update transport state)

Signed-off-by: Zijie Pan <zijie.pan@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: check src addr when processing SACK to update transport state

Suppose we have an SCTP connection with two paths. After connection is
established, path1 is not available, thus this path is marked as inactive. Then
traffic goes through path2, but for some reasons packets are delayed (after
rto.max). Because packets are delayed, the retransmit mechanism will switch
again to path1. At this time, we receive a delayed SACK from path2. When we
update the state of the path in sctp_check_transmitted(), we do not take into
account the source address of the SACK, hence we update the wrong path.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Push struct net down into all of the state machine functions

There are a handle of state machine functions primarily those dealing
with processing INIT packets where there is neither a valid endpoint nor
a valid assoication from which to derive a struct net. Therefore add
struct net * to the parameter list of sctp_state_fn_t and update all of
the state machine functions.

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

sctp: Push struct net down to sctp_chunk_event_lookup

This trickles up through sctp_sm_lookup_event up to sctp_do_sm
and up further into sctp_primitiv_NAME before the code reaches
places where struct net can be reliably found.

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

sctp: Implement quick failover draft from tsvwg

I've seen several attempts recently made to do quick failover of sctp transports
by reducing various retransmit timers and counters. While its possible to
implement a faster failover on multihomed sctp associations, its not
particularly robust, in that it can lead to unneeded retransmits, as well as
false connection failures due to intermittent latency on a network.

Instead, lets implement the new ietf quick failover draft found here:
http://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05

This will let the sctp stack identify transports that have had a small number of
errors, and avoid using them quickly until their reliability can be
re-established. I've tested this out on two virt guests connected via multiple
isolated virt networks and believe its in compliance with the above draft and
works well.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Sridhar Samudrala <sri@us.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
CC: joe@perches.com
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: be more restrictive in transport selection on bundled sacks

It was noticed recently that when we send data on a transport, its possible that
we might bundle a sack that arrived on a different transport. While this isn't
a major problem, it does go against the SHOULD requirement in section 6.4 of RFC
2960:

An endpoint SHOULD transmit reply chunks (e.g., SACK, HEARTBEAT ACK,
etc.) to the same destination transport address from which it
received the DATA or control chunk to which it is replying. This
rule should also be followed if the endpoint is bundling DATA chunks
together with the reply chunk.

This patch seeks to correct that. It restricts the bundling of sack operations
to only those transports which have moved the ctsn of the association forward
since the last sack. By doing this we guarantee that we only bundle outbound
saks on a transport that has received a chunk since the last sack. This brings
us into stricter compliance with the RFC.

Vlad had initially suggested that we strictly allow only sack bundling on the
transport that last moved the ctsn forward. While this makes sense, I was
concerned that doing so prevented us from bundling in the case where we had
received chunks that moved the ctsn on multiple transports. In those cases, the
RFC allows us to select any of the transports having received chunks to bundle
the sack on. so I've modified the approach to allow for that, by adding a state
variable to each transport that tracks weather it has moved the ctsn since the
last sack. This I think keeps our behavior (and performance), close enough to
our current profile that I think we can do this without a sysctl knob to
enable/disable it.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yaseivch <vyasevich@gmail.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
Reported-by: Michele Baldessari <michele@redhat.com>
Reported-by: sorin serban <sserban@redhat.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Convert net_ratelimit uses to net_<level>_ratelimited

Standardize the net core ratelimited logging functions.

Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: cleanup unsigned to unsigned int

Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fasthandoff with ASCONF at server-node

Retransmit chunks to newly confirmed destination when ASCONF and
HEARTBEAT negotiation has success with a single-homed peer.

Signed-off-by: Michio Honda <micchie@sfc.wide.ad.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: deal with multiple COOKIE_ECHO chunks

Attempt to reduce the number of IP packets emitted in response to single
SCTP packet (2e3216cd) introduced a complication - if a packet contains
two COOKIE_ECHO chunks and nothing else then SCTP state machine corks the
socket while processing first COOKIE_ECHO and then loses the association
and forgets to uncork the socket. To deal with the issue add new SCTP
command which can be used to set association explictly. Use this new
command when processing second COOKIE_ECHO chunk to restore the context
for SCTP state machine.

Signed-off-by: Max Matveev <makc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Enforce retransmission limit during shutdown

When initiating a graceful shutdown while having data chunks
on the retransmission queue with a peer which is in zero
window mode the shutdown is never completed because the
retransmission error count is reset periodically by the
following two rules:

- Do not timeout association while doing zero window probe.
- Reset overall error count when a heartbeat request has
been acknowledged.

The graceful shutdown will wait for all outstanding TSN to
be acknowledged before sending the SHUTDOWN request. This
never happens due to the peer's zero window not acknowledging
the continuously retransmitted data chunks. Although the
error counter is incremented for each failed retransmission,
the receiving of the SACK announcing the zero window clears
the error count again immediately. Also heartbeat requests
continue to be sent periodically. The peer acknowledges these
requests causing the error counter to be reset as well.

This patch changes behaviour to only reset the overall error
counter for the above rules while not in shutdown. After
reaching the maximum number of retransmission attempts, the
T5 shutdown guard timer is scheduled to give the receiver
some additional time to recover. The timer is stopped as soon
as the receiver acknowledges any data.

The issue can be easily reproduced by establishing a sctp
association over the loopback device, constantly queueing
data at the sender while not reading any at the receiver.
Wait for the window to reach zero, then initiate a shutdown
by killing both processes simultaneously. The association
will never be freed and the chunks on the retransmission
queue will be retransmitted indefinitely.

Signed-off-by: Thomas Graf <tgraf@infradead.org>
Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Remove casts of void *

Unnecessary casts of void * clutter the code.

These are the remainder casts after several specific
patches to remove netdev_priv and dev_priv.

Done via coccinelle script:

$ cat cast_void_pointer.cocci
@@
type T;
T *pt;
void *pv;
@@

- pt = (T *)pv;
+ pt = pv;

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>

sctp: stop pending timers and purge queues when peer restart asoc

If the peer restart the asoc, we should not only fail any unsent/unacked
data, but also stop the T3-rtx, SACK, T4-rto timers, and teardown ASCONF
queues.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fix to check the source address of COOKIE-ECHO chunk

SCTP does not check whether the source address of COOKIE-ECHO
chunk is the original address of INIT chunk or part of the any
address parameters saved in COOKIE in CLOSED state. So even if
the COOKIE-ECHO chunk is from any address but with correct COOKIE,
the COOKIE-ECHO chunk still be accepted. If the COOKIE is not from
a valid address, the assoc should not be established.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: kill abandoned SCTP_CMD_TRANSMIT command

Remove SCTP_CMD_TRANSMIT command as it never be used.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

net/sctp: Use pr_fmt and pr_<level>

Change SCTP_DEBUG_PRINTK and SCTP_DEBUG_PRINTK_IPADDR to
use do { print } while (0) guards.
Add SCTP_DEBUG_PRINTK_CONT to fix errors in log when
lines were continued.
Add #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
Add a missing newline in "Failed bind hash alloc"

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Remove unnecessary returns from void function()s

This patch removes from net/ (but not any netfilter files)
all the unnecessary return; statements that precede the
last closing brace of void functions.

It does not remove the returns that are immediately
preceded by a label as gcc doesn't like that.

Done via:
$ grep -rP --include=*.[ch] -l "return;\n}" net/ | \
xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }'

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Fix a race between ICMP protocol unreachable and connect()

ICMP protocol unreachable handling completely disregarded
the fact that the user may have locked the socket. It proceeded
to destroy the association, even though the user may have
held the lock and had a ref on the association. This resulted
in the following:

Attempt to release alive inet socket f6afcc00

=========================
[ BUG: held lock freed! ]
-------------------------
somenu/2672 is freeing memory f6afcc00-f6afcfff, with a lock still held
there!
(sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c
1 lock held by somenu/2672:
#0: (sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c

stack backtrace:
Pid: 2672, comm: somenu Not tainted 2.6.32-telco #55
Call Trace:
[<c1232266>] ? printk+0xf/0x11
[<c1038553>] debug_check_no_locks_freed+0xce/0xff
[<c10620b4>] kmem_cache_free+0x21/0x66
[<c1185f25>] __sk_free+0x9d/0xab
[<c1185f9c>] sk_free+0x1c/0x1e
[<c1216e38>] sctp_association_put+0x32/0x89
[<c1220865>] __sctp_connect+0x36d/0x3f4
[<c122098a>] ? sctp_connect+0x13/0x4c
[<c102d073>] ? autoremove_wake_function+0x0/0x33
[<c12209a8>] sctp_connect+0x31/0x4c
[<c11d1e80>] inet_dgram_connect+0x4b/0x55
[<c11834fa>] sys_connect+0x54/0x71
[<c103a3a2>] ? lock_release_non_nested+0x88/0x239
[<c1054026>] ? might_fault+0x42/0x7c
[<c1054026>] ? might_fault+0x42/0x7c
[<c11847ab>] sys_socketcall+0x6d/0x178
[<c10da994>] ? trace_hardirqs_on_thunk+0xc/0x10
[<c1002959>] syscall_call+0x7/0xb

This was because the sctp_wait_for_connect() would aqcure the socket
lock and then proceed to release the last reference count on the
association, thus cause the fully destruction path to finish freeing
the socket.

The simplest solution is to start a very short timer in case the socket
is owned by user. When the timer expires, we can do some verification
and be able to do the release properly.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: send SHUTDOWN-ACK chunk back to the source.

SHUTDOWN-ACK is alaways sent to the primary path at the first time,
but should better transmit SHUTDOWN-ACK chunk to the same destination
transport address from which it received the SHUTDOWN chunk.
Based on the work from Wei Yongjun <yjwei@cn.fujitsu.com>.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: Fix oops when sending queued ASCONF chunks

When we finish processing ASCONF_ACK chunk, we try to send
the next queued ASCONF. This action runs the sctp state
machine recursively and it's not prepared to do so.

kernel BUG at kernel/timer.c:790!
invalid opcode: 0000 [#1] SMP
last sysfs file: /sys/module/ipv6/initstate
Modules linked in: sha256_generic sctp libcrc32c ipv6 dm_multipath
uinput 8139too i2c_piix4 8139cp mii i2c_core pcspkr virtio_net joydev
floppy virtio_blk virtio_pci [last unloaded: scsi_wait_scan]

Pid: 0, comm: swapper Not tainted 2.6.34-rc4 #15 /Bochs
EIP: 0060:[<c044a2ef>] EFLAGS: 00010286 CPU: 0
EIP is at add_timer+0xd/0x1b
EAX: cecbab14 EBX: 000000f0 ECX: c0957b1c EDX: 03595cf4
ESI: cecba800 EDI: cf276f00 EBP: c0957aa0 ESP: c0957aa0
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process swapper (pid: 0, ti=c0956000 task=c0988ba0 task.ti=c0956000)
Stack:
c0957ae0 d1851214 c0ab62e4 c0ab5f26 0500ffff 00000004 00000005 00000004
<0> 00000000 d18694fd 00000004 1666b892 cecba800 cecba800 c0957b14
00000004
<0> c0957b94 d1851b11 ceda8b00 cecba800 cf276f00 00000001 c0957b14
000000d0
Call Trace:
[<d1851214>] ? sctp_side_effects+0x607/0xdfc [sctp]
[<d1851b11>] ? sctp_do_sm+0x108/0x159 [sctp]
[<d1863386>] ? sctp_pname+0x0/0x1d [sctp]
[<d1861a56>] ? sctp_primitive_ASCONF+0x36/0x3b [sctp]
[<d185657c>] ? sctp_process_asconf_ack+0x2a4/0x2d3 [sctp]
[<d184e35c>] ? sctp_sf_do_asconf_ack+0x1dd/0x2b4 [sctp]
[<d1851ac1>] ? sctp_do_sm+0xb8/0x159 [sctp]
[<d1863334>] ? sctp_cname+0x0/0x52 [sctp]
[<d1854377>] ? sctp_assoc_bh_rcv+0xac/0xe1 [sctp]
[<d1858f0f>] ? sctp_inq_push+0x2d/0x30 [sctp]
[<d186329d>] ? sctp_rcv+0x797/0x82e [sctp]

Tested-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Yuansong Qiao <ysqiao@research.ait.ie>
Signed-off-by: Shuaijun Zhang <szhang@research.ait.ie>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

tree-wide: Assorted spelling fixes

In particular, several occurances of funny versions of 'success',
'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address',
'beginning', 'desirable', 'separate' and 'necessary' are fixed.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Joe Perches <joe@perches.com>
Cc: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

tree-wide: fix assorted typos all over the place

That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperature"
, "channel", "[un]used", "application", "example","hierarchy", "therefore"
, "[over|under]flow", "contiguous", "threshold", "enough" and others.

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

sctp: on T3_RTX retransmit all the in-flight chunks

When retransmitting due to T3 timeout, retransmit all the
in-flight chunks for the corresponding transport/path, including
chunks sent less then 1 rto ago.
This is the correct behaviour according to rfc4960 section 6.3.3
E3 and
"Note: Any DATA chunks that were sent to the address for which the
T3-rtx timer expired but did not fit in one MTU (rule E3 above)
should be marked for retransmission and sent as soon as cwnd
allows (normally, when a SACK arrives). ".

This fixes problems when more then one path is present and the T3
retransmission of the first chunk that timeouts stops the T3 timer
for the initial active path, leaving all the other in-flight
chunks waiting forever or until a new chunk is transmitted on the
same path and timeouts (and this will happen only if the cwnd
allows sending new chunks, but since cwnd was dropped to MTU by
the timeout => it will wait until the first heartbeat).

Example: 10 packets in flight, sent at 0.1 s intervals on the
primary path. The primary path is down and the first packet
timeouts. The first packet is retransmitted on another path, the
T3 timer for the primary path is stopped and cwnd is set to MTU.
All the other 9 in-flight packets will not be retransmitted
(unless more new packets are sent on the primary path which depend
on cwnd allowing it, and even in this case the 9 packets will be
retransmitted only after a new packet timeouts which even in the
best case would be more then RTO).

This commit reverts d0ce92910bc04e107b2f3f2048f07e94f570035d and
also removes the now unused transport->last_rto, introduced in
b6157d8e03e1e780660a328f7183bcbfa4a93a19.

p.s The problem is not only when multiple paths are there. It
can happen in a single homed environment. If the application
stops sending data, it possible to have a hung association.

Signed-off-by: Andrei Pelinescu-Onciul <andrei@iptel.org>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Update SWS avaoidance receiver side algorithm

We currently send window update SACKs every time we free up 1 PMTU
worth of data. That a lot more SACKs then necessary. Instead, we'll
now send back the actuall window every time we send a sack, and do
window-update SACKs when a fraction of the receive buffer has been
opened. The fraction is controlled with a sysctl.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: Select a working primary during sctp_connectx()

When sctp_connectx() is used, we pick the first address as
primary, even though it may not have worked. This results
in excessive retransmits and poor performance. We should
select the address that the association was established with.

Reported-by: Thomas Dreibholz <dreibh@iem.uni-due.de>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: Try not to change a_rwnd when faking a SACK from SHUTDOWN.

We currently set a_rwnd to 0 when faking a SACK from SHUTDOWN.
This results in an hung association if the remote only uses
SHUTDOWNs (which it's allowed to do) to acknowlege DATA when
closing. The reason for that is that we simply honor the a_rwnd
from the sack, but since we faked it to be 0, we enter 0-window
probing. The fix is to use the peers old rwnd and add our flight
size to it.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: Fix error count increments that were results of HEARTBEATS

SCTP RFC 4960 states that unacknowledged HEARTBEATS count as
errors agains a given transport or endpoint. As such, we
should increment the error counts for only for unacknowledged
HB, otherwise we detect failure too soon. This goes for both
the overall error count and the path error count.

Now, there is a difference in how the detection is done
between the two. The path error detection is done after
the increment, so to detect it properly, we actually need
to exceed the path threshold. The overall error detection
is done _BEFORE_ the increment. Thus to detect the failure,
it's enough for the error count to match the threshold.
This is why all the state functions use '>=' to detect failure,
while path detection uses '>'.

Thanks goes to Chunbo Luo <chunbo.luo@windriver.com> who first
proposed patches to fix this issue and made me re-read the spec
and the code to figure out how this cruft really works.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: Send user messages to the lower layer as one

Currenlty, sctp breaks up user messages into fragments and
sends each fragment to the lower layer by itself. This means
that for each fragment we go all the way down the stack
and back up. This also discourages bundling of multiple
fragments when they can fit into a sigle packet (ex: due
to user setting a low fragmentation threashold).

We introduce a new command SCTP_CMD_SND_MSG and hand the
whole message down state machine. The state machine and
the side-effect parser will cork the queue, add all chunks
from the message to the queue, and then un-cork the queue
thus causing the chunks to get transmitted.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: fix to choose alternate destination when retransmit ASCONF chunk

RFC 5061 Section 5.1 ASCONF Chunk Procedures said:

B4) Re-transmit the ASCONF Chunk last sent and if possible choose an
alternate destination address (please refer to [RFC4960],
Section 6.4.1). An endpoint MUST NOT add new parameters to this
chunk; it MUST be the same (including its Sequence Number) as
the last ASCONF sent. An endpoint MAY, however, bundle an
additional ASCONF with new ASCONF parameters with the next
Sequence Number. For details, see Section 5.5.

This patch fix to choose an alternate destination address when
re-transmit the ASCONF chunk, with some dup codes cleanup.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: Fix broken RTO-doubling for data retransmits

Commit faee47cdbfe8d74a1573c2f81ea6dbb08d735be6
(sctp: Fix the RTO-doubling on idle-link heartbeats)
broke the RTO doubling for data retransmits. If the
heartbeat was sent before the data T3-rtx time, the
the RTO will not double upon the T3-rtx expiration.
Distingish between the operations by passing an argument
to the function.

Additionally, Wei Youngjun pointed out that our treatment
of requested HEARTBEATS and timer HEARTBEATS is the same
wrt resetting congestion window. That needs to be separated,
since user requested HEARTBEATS should not treat the link
as idle.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: fix kernel panic with ERROR chunk containing too many error causes

If ERROR chunk is received with too many error causes in ESTABLISHED
state, the kernel get panic.

This is because sctp limit the max length of cmds to 14, but while
ERROR chunk is received, one error cause will add around 2 cmds by
sctp_add_cmd_sf(). So many error causes will fill the limit of cmds
and panic.

This patch fixed the problem.

This bug can be test by SCTP Conformance Test Suite
<http://networktest.sourceforge.net/>.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Fix the RTO-doubling on idle-link heartbeats

SCTP incorrectly doubles rto ever time a Hearbeat chunk
is generated. However RFC 4960 states:

On an idle destination address that is allowed to heartbeat, it is
recommended that a HEARTBEAT chunk is sent once per RTO of that
destination address plus the protocol parameter 'HB.interval', with
jittering of +/- 50% of the RTO value, and exponential backoff of the
RTO if the previous HEARTBEAT is unanswered.

Essentially, of if the heartbean is unacknowledged, do we double the RTO.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Rework the tsn map to use generic bitmap.

The tsn map currently use is 4K large and is stuck inside
the sctp_association structure making memory references REALLY
expensive. What we really need is at most 4K worth of bits
so the biggest map we would have is 512 bytes. Also, the
map is only really usefull when we have gaps to store and
report. As such, starting with minimal map of say 32 TSNs (bits)
should be enough for normal low-loss operations. We can grow
the map by some multiple of 32 along with some extra room any
time we receive the TSN which would put us outside of the map
boundry. As we close gaps, we can shift the map to rebase
it on the latest TSN we've seen. This saves 4088 bytes per
association just in the map alone along savings from the now
unnecessary structure members.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: enable cookie-echo retransmission transport switch

This patch enables cookie-echo retransmission transport switch
feature. If COOKIE-ECHO retransmission happens, it will be sent
to the address other than the one last sent to.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

sctp: Follow security requirement of responding with 1 packet

RFC 4960, Section 11.4. Protection of Non-SCTP-Capable Hosts

When an SCTP stack receives a packet containing multiple control or
DATA chunks and the processing of the packet requires the sending of
multiple chunks in response, the sender of the response chunk(s) MUST
NOT send more than one packet. If bundling is supported, multiple
response chunks that fit into a single packet MAY be bundled together
into one single response packet. If bundling is not supported, then
the sender MUST NOT send more than one response chunk and MUST
discard all other responses. Note that this rule does NOT apply to a
SACK chunk, since a SACK chunk is, in itself, a response to DATA and
a SACK does not require a response of more DATA.

We implement this by not servicing our outqueue until we reach the end
of the packet. This enables maximum bundling. We also identify
'response' chunks and make sure that we only send 1 packet when sending
such chunks.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp: Bring SCTP_DELAYED_ACK socket option into API compliance

Brings delayed_ack socket option set/get into line with the latest ietf
socket extensions API draft, while maintaining backwards compatibility.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Remove an unused parameter from sctp_cmd_hb_timer_update

The 'asoc' parameter to sctp_cmd_hb_timer_update() is unused, and
we can remove it.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: "list_for_each()" -> "list_for_each_entry()" where appropriate.

Replacing (almost) all invocations of list_for_each() with
list_for_each_entry() tightens up the code and allows for the deletion
of numerous list iterator variables that are no longer necessary.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Fix protocol violation when receiving an error lenght INIT-ACK

When receiving an error length INIT-ACK during COOKIE-WAIT,
a 0-vtag ABORT will be responsed. This action violates the
protocol apparently. This patch achieves the following things.
1 If the INIT-ACK contains all the fixed parameters, use init-tag
recorded from INIT-ACK as vtag.
2 If the INIT-ACK doesn't contain all the fixed parameters,
just reflect its vtag.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Stop claiming that this is a "reference implementation"

I was notified by Randy Stewart that lksctp claims to be
"the reference implementation". First of all, "the
refrence implementation" was the original implementation
of SCTP in usersapce written ty Randy and a few others.
Second, after looking at the definiton of 'reference implementation',
we don't really meet the requirements.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

SCTP: Fix difference cases of retransmit.

Commit d0ce92910bc04e107b2f3f2048f07e94f570035d broke several retransmit
cases including fast retransmit. The reason is that we should
only delay by rto while doing retranmists as a result of a timeout.
Retransmit as a result of path mtu discover, fast retransmit, or
other evernts that should trigger immidiate retransmissions got broken.

Also, since rto is doubled prior to marking of packets elegable for
retransmission, we never marked correct chunks anyway.

The fix is provide a reason for a given retransmission so that we
can mark chunks appropriately and to save the old rto value to do
comparisons against.

All regressions tests passed with this code.

Spotted by Wei Yongjun <yjwei@cn.fujitsu.com>

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

[SCTP]: Implete SCTP-AUTH parameter processing

Implement processing for the CHUNKS, RANDOM, and HMAC parameters and
deal with how this parameters are effected by association restarts.
In particular, during unexpeted INIT processing, we need to reply with
parameters from the original INIT chunk. Also, after restart, we need
to update the old association with new peer parameters and change the
association shared keys.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

SCTP: Use net_ratelimit to suppress error messages print too fast

When multi bundling SHUTDOWN-ACK message is received in ESTAB state,
this will cause "sctp protocol violation state" message print many times.
If SHUTDOWN-ACK is bundled 300 times in one packet, message will be
print 300 times. The same problem also exists when received unexpected
HEARTBEAT-ACK message which is bundled message times.

This patch used net_ratelimit() to suppress error messages print too fast.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

SCTP: properly clean up fragment and ordering queues during FWD-TSN.

When we recieve a FWD-TSN (meaning the peer has abandoned the data),
we need to clean up any partially received messages that may be
hanging out on the re-assembly or re-ordering queues. This is
a MUST requirement that was not properly done before.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com.>

[SCTP]: Set assoc_id correctly during INIT collision.

During the INIT/COOKIE-ACK collision cases, it's possible to get
into a situation where the association id is not yet set at the time
of the user event generation. As a result, user events have an
association id set to 0 which will confuse applications.

This happens if we hit case B of duplicate cookie processing.
In the particular example found and provided by Oscar Isaula
<Oscar.Isaula@motorola.com>, flow looks like this:
A B
---- INIT-------> (lost)
<---------INIT------
---- INIT-ACK--->
<------ Cookie ECHO

When the Cookie Echo is received, we end up trying to update the
association that was created on A as a result of the (lost) INIT,
but that association doesn't have the ID set yet.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: cleanup extra semicolons

Spring cleaning time...

There seems to be a lot of places in the network code that have
extra bogus semicolons after conditionals. Most commonly is a
bogus semicolon after: switch() { }

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Implement sac_info field in SCTP_ASSOC_CHANGE notification.

As stated in the sctp socket api draft:

sac_info: variable

If the sac_state is SCTP_COMM_LOST and an ABORT chunk was received
for this association, sac_info[] contains the complete ABORT chunk as
defined in the SCTP specification RFC2960 [RFC2960] section 3.3.7.

We now save received ABORT chunks into the sac_info field and pass that
to the user.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET] SCTP: Fix whitespace errors.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Force update of the rto when processing HB-ACK

When processing a HEARTBEAT-ACK it's possible that the transport rto
timers will not be updated because a prior T3-RTX processing would
have cleared the rto_pending flag on the transport. However, if
we received a valid HEARTBEAT-ACK, we want to force update the
rto variables, so re-set the rto_pending flag before calling
sctp_transport_update_rto().

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Fix SACK sequence during shutdown

Currently, when association enters SHUTDOWN state,the
implementation will SACK any DATA first and then transmit
the SHUTDOWN chunk. This is against the order required by
2960bis spec. SHUTDOWN must always be first, followed by
SACK. This change forces this order and also enables bundling.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: SCTP_CMD_PROCESS_CTSN annotations.

argument passed as __be32

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Trivial ->ipaddr_h -> ->ipaddr conversions.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: sctp_assoc_del_peer() switched to net-endian.

Callers adjusted.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Switch ->primary_addr to net-endian.

Users adjusted.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Switch ->cmp_addr() and sctp_cmp_addr_exact() to net-endian.

instances of ->cmp_addr() are fine with switching both arguments
to net-endian; callers other than in sctp_cmp_addr_exact() (both
as ->cmp_addr(...) and direct calls of instances) adjusted;
sctp_cmp_addr_exact() switched to net-endian itself and adjustment
is done in its callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Beginning of conversion to net-endian for embedded sctp_addr.

Part 1: rename sctp_chunk->source, sctp_sockaddr_entry->a,
sctp_transport->ipaddr and sctp_transport->saddr (to ..._h)

The next patch will reintroduce these fields and keep them as
net-endian mirrors of the original (renamed) ones. Split in
two patches to make sure that we hadn't forgotten any instanes.

Later in the series we'll eliminate uses of host-endian variants
(basically switching users to net-endian counterparts as we
progress through that mess). Then host-endian ones will die.

Other embedded host-endian sctp_addr will be easier to switch
directly, so we leave them alone for now.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: SCTP_CMD_ASSOC_FAILED annotations.

also always get __be16 protocol error; switch to SCTP_PERR()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: SCTP_CMD_INIT_FAILED annotations.

argument stored for SCTP_CMD_INIT_FAILED is always __be16
(protocol error). Introduced new field and accessor for
it (SCTP_PERR()); switched to their use (from SCTP_U32() and
.u32)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Verify all the paths to a peer via heartbeat before using them.

This patch implements Path Initialization procedure as described in
Sec 2.36 of RFC4460.

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Set sk_err so that poll wakes up after a non-blocking connect failure.

Also fix some other cases where sk_err is not set for 1-1 style sockets.

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>

[SCTP]: Fix bad sysctl formatting of SCTP timeout values on 64-bit m/cs.

Change all the structure members that hold jiffies to be of type
unsigned long. This also corrects bad sysctl formating on 64 bit
architectures.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>

[NET]: Change some "if (x) BUG();" to "BUG_ON(x);"

This changes some simple "if (x) BUG();" statements to "BUG_ON(x);"

Signed-off-by: Kris Katterjohn <kjak@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Update SCTP_PEER_ADDR_PARAMS socket option to the latest api draft.

This patch adds support to set/get heartbeat interval, maximum number of
retransmissions, pathmtu, sackdelay time for a particular transport/
association/socket as per the latest SCTP sockets api draft11.

Signed-off-by: Frank Filz <ffilz@us.ibm.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP]: Remove timeouts[] array from sctp_endpoint.

The socket level timeout values are maintained in sctp_sock and
association level timeouts are in sctp_association. So there is
no need for ep->timeouts.

Signed-off-by: Vladislav Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[PATCH] gfp flags annotations - part 1

- added typedef unsigned int __nocast gfp_t;

- replaced __nocast uses for gfp flags with gfp_t - it gives exactly
the same warnings as far as sparse is concerned, doesn't change
generated code (from gcc point of view we replaced unsigned int with
typedef) and documents what's going on far better.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[SCTP]: __nocast annotations

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SCTP] sctp_connectx() API support

Implements sctp_connectx() as defined in the SCTP sockets API draft by
tunneling the request through a setsockopt().

Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!