kernel/linux.git/net/sctp/inqueue.c, branch v6.12.80

sctp: avoid NULL dereference when chunk data buffer is missing

2025-10-29T13:08:55+00:00

[ Upstream commit 441f0647f7673e0e64d4910ef61a5fb8f16bfb82 ] chunk->skb pointer is dereferenced in the if-block where it's supposed to be NULL only. chunk->skb can only be NULL if chunk->head_skb is not. Check for frag_list instead and do it just before replacing chunk->skb. We're sure that otherwise chunk->skb is non-NULL because of outer if() condition. Fixes: 90017accff61 ("sctp: Add GSO support") Signed-off-by: Alexey Simakov Acked-by: Marcelo Ricardo Leitner Link: https://patch.msgid.link/20251021130034.6333-1-bigalex934@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: sctp: fix skb leak in sctp_inq_free()

2024-02-15T15:34:52+00:00

In case of GSO, 'chunk->skb' pointer may point to an entry from fraglist created in 'sctp_packet_gso_append()'. To avoid freeing random fraglist entry (and so undefined behavior and/or memory leak), introduce 'sctp_inq_chunk_free()' helper to ensure that 'chunk->skb' is set to 'chunk->head_skb' (i.e. fraglist head) before calling 'sctp_chunk_free()', and use the aforementioned helper in 'sctp_inq_pop()' as well. Reported-by: syzbot+8bb053b5d63595ab47db@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?id=0d8351bbe54fd04a492c2daab0164138db008042 Fixes: 90017accff61 ("sctp: Add GSO support") Suggested-by: Xin Long Signed-off-by: Dmitry Antipov Acked-by: Xin Long Link: https://lore.kernel.org/r/20240214082224.10168-1-dmantipov@yandex.ru Signed-off-by: Jakub Kicinski

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

2019-05-24T15:39:00+00:00

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 Reviewed-by: Kate Stewart Reviewed-by: Richard Fontana Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190523091649.683323110@linutronix.de Signed-off-by: Greg Kroah-Hartman

sctp: fix the issue that the cookie-ack with auth can't get processed

2018-05-02T15:15:33+00:00

When auth is enabled for cookie-ack chunk, in sctp_inq_pop, sctp processes auth chunk first, then continues to the next chunk in this packet if chunk_end + chunk_hdr size < skb_tail_pointer(). Otherwise, it will go to the next packet or discard this chunk. However, it missed the fact that cookie-ack chunk's size is equal to chunk_hdr size, which couldn't match that check, and thus this chunk would not get processed. This patch fixes it by changing the check to chunk_end + chunk_hdr size <= skb_tail_pointer(). Fixes: 26b87c788100 ("net: sctp: fix remote memory pressure from excessive queueing") Signed-off-by: Xin Long Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

net: use skb_is_gso_sctp() instead of open-coding

2018-03-09T16:41:47+00:00

As well as the basic conversion, I noticed that a lot of the SCTP code checks gso_type without first checking skb_is_gso() so I have added that where appropriate. Also, document the helper. Cc: Daniel Borkmann Cc: Marcelo Ricardo Leitner Signed-off-by: Daniel Axtens Signed-off-by: David S. Miller

sctp: remove the typedef sctp_chunkhdr_t

2017-07-01T16:08:41+00:00

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 Signed-off-by: David S. Miller

sctp: rename WORD_TRUNC/ROUND macros

2016-09-22T07:13:26+00:00

To something more meaningful these days, specially because this is working on packet headers or lengths and which are not tied to any CPU arch but to the protocol itself. So, WORD_TRUNC becomes SCTP_TRUNC4 and WORD_ROUND becomes SCTP_PAD4. Reported-by: David Laight Reported-by: David Miller Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: linearize early if it's not GSO

2016-08-20T00:09:42+00:00

Because otherwise when crc computation is still needed it's way more expensive than on a linear buffer to the point that it affects performance. It's so expensive that netperf test gives a perf output as below: Overhead Command Shared Object Symbol 18,62% netserver [kernel.vmlinux] [k] crc32_generic_shift 2,57% netserver [kernel.vmlinux] [k] __pskb_pull_tail 1,94% netserver [kernel.vmlinux] [k] fib_table_lookup 1,90% netserver [kernel.vmlinux] [k] copy_user_enhanced_fast_string 1,66% swapper [kernel.vmlinux] [k] intel_idle 1,63% netserver [kernel.vmlinux] [k] _raw_spin_lock 1,59% netserver [sctp] [k] sctp_packet_transmit 1,55% netserver [kernel.vmlinux] [k] memcpy_erms 1,42% netserver [sctp] [k] sctp_rcv # netperf -H 192.168.10.1 -l 10 -t SCTP_STREAM -cC -- -m 12000 SCTP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.10.1 () port 0 AF_INET Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 212992 212992 12000 10.00 3016.42 2.88 3.78 1.874 2.462 After patch: Overhead Command Shared Object Symbol 2,75% netserver [kernel.vmlinux] [k] memcpy_erms 2,63% netserver [kernel.vmlinux] [k] copy_user_enhanced_fast_string 2,39% netserver [kernel.vmlinux] [k] fib_table_lookup 2,04% netserver [kernel.vmlinux] [k] __pskb_pull_tail 1,91% netserver [kernel.vmlinux] [k] _raw_spin_lock 1,91% netserver [sctp] [k] sctp_packet_transmit 1,72% netserver [mlx4_en] [k] mlx4_en_process_rx_cq 1,68% netserver [sctp] [k] sctp_rcv # netperf -H 192.168.10.1 -l 10 -t SCTP_STREAM -cC -- -m 12000 SCTP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.10.1 () port 0 AF_INET Recv Send Send Utilization Service Demand Socket Socket Message Elapsed Send Recv Send Recv Size Size Size Time Throughput local remote local remote bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB 212992 212992 12000 10.00 3681.77 3.83 3.46 2.045 1.849 Fixes: 3acb50c18d8d ("sctp: delay as much as possible skb_linearize") Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: fix BH handling on socket backlog

2016-07-25T18:22:22+00:00

Now that the backlog processing is called with BH enabled, we have to disable BH before taking the socket lock via bh_lock_sock() otherwise it may dead lock: sctp_backlog_rcv() bh_lock_sock(sk); if (sock_owned_by_user(sk)) { if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) sctp_chunk_free(chunk); else backloged = 1; } else sctp_inq_push(inqueue, chunk); bh_unlock_sock(sk); while sctp_inq_push() was disabling/enabling BH, but enabling BH triggers pending softirq, which then may try to re-lock the socket in sctp_rcv(). [ 219.187215] [ 219.187217] [] _raw_spin_lock+0x20/0x30 [ 219.187223] [] sctp_rcv+0x48c/0xba0 [sctp] [ 219.187225] [] ? nf_iterate+0x62/0x80 [ 219.187226] [] ip_local_deliver_finish+0x94/0x1e0 [ 219.187228] [] ip_local_deliver+0x6f/0xf0 [ 219.187229] [] ? ip_rcv_finish+0x3b0/0x3b0 [ 219.187230] [] ip_rcv_finish+0xd8/0x3b0 [ 219.187232] [] ip_rcv+0x282/0x3a0 [ 219.187233] [] ? update_curr+0x66/0x180 [ 219.187235] [] __netif_receive_skb_core+0x524/0xa90 [ 219.187236] [] ? update_cfs_shares+0x30/0xf0 [ 219.187237] [] ? __enqueue_entity+0x6c/0x70 [ 219.187239] [] ? enqueue_entity+0x204/0xdf0 [ 219.187240] [] __netif_receive_skb+0x18/0x60 [ 219.187242] [] process_backlog+0x9e/0x140 [ 219.187243] [] net_rx_action+0x22c/0x370 [ 219.187245] [] __do_softirq+0x112/0x2e7 [ 219.187247] [] do_softirq_own_stack+0x1c/0x30 [ 219.187247] [ 219.187248] [] do_softirq.part.14+0x38/0x40 [ 219.187249] [] __local_bh_enable_ip+0x7d/0x80 [ 219.187254] [] sctp_inq_push+0x68/0x80 [sctp] [ 219.187258] [] sctp_backlog_rcv+0x151/0x1c0 [sctp] [ 219.187260] [] __release_sock+0x87/0xf0 [ 219.187261] [] release_sock+0x30/0xa0 [ 219.187265] [] sctp_accept+0x17d/0x210 [sctp] [ 219.187266] [] ? prepare_to_wait_event+0xf0/0xf0 [ 219.187268] [] inet_accept+0x3c/0x130 [ 219.187269] [] SYSC_accept4+0x103/0x210 [ 219.187271] [] ? _raw_spin_unlock_bh+0x1a/0x20 [ 219.187272] [] ? release_sock+0x8c/0xa0 [ 219.187276] [] ? sctp_inet_listen+0x62/0x1b0 [sctp] [ 219.187277] [] SyS_accept+0x10/0x20 Fixes: 860fbbc343bf ("sctp: prepare for socket backlog behavior change") Cc: Eric Dumazet Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: do not clear chunk->ecn_ce_done flag

2016-07-14T01:10:14+00:00

We should not clear that flag when switching to a new skb from a GSO skb because it would cause ECN processing to happen multiple times per GSO skb, which is not wanted. Instead, let it be processed once per chunk. That is, in other words, once per IP header available. Fixes: 90017accff61 ("sctp: Add GSO support") Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller