linux/net/sctp
Eric Dumazet 10206302af sctp: add mutual exclusion in proc_sctp_do_udp_port()
We must serialize calls to sctp_udp_sock_stop() and sctp_udp_sock_start()
or risk a crash as syzbot reported:

Oops: general protection fault, probably for non-canonical address 0xdffffc000000000d: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
CPU: 1 UID: 0 PID: 6551 Comm: syz.1.44 Not tainted 6.14.0-syzkaller-g7f2ff7b62617 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
 RIP: 0010:kernel_sock_shutdown+0x47/0x70 net/socket.c:3653
Call Trace:
 <TASK>
  udp_tunnel_sock_release+0x68/0x80 net/ipv4/udp_tunnel_core.c:181
  sctp_udp_sock_stop+0x71/0x160 net/sctp/protocol.c:930
  proc_sctp_do_udp_port+0x264/0x450 net/sctp/sysctl.c:553
  proc_sys_call_handler+0x3d0/0x5b0 fs/proc/proc_sysctl.c:601
  iter_file_splice_write+0x91c/0x1150 fs/splice.c:738
  do_splice_from fs/splice.c:935 [inline]
  direct_splice_actor+0x18f/0x6c0 fs/splice.c:1158
  splice_direct_to_actor+0x342/0xa30 fs/splice.c:1102
  do_splice_direct_actor fs/splice.c:1201 [inline]
  do_splice_direct+0x174/0x240 fs/splice.c:1227
  do_sendfile+0xafd/0xe50 fs/read_write.c:1368
  __do_sys_sendfile64 fs/read_write.c:1429 [inline]
  __se_sys_sendfile64 fs/read_write.c:1415 [inline]
  __x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1415
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]

Fixes: 046c052b47 ("sctp: enable udp tunneling socks")
Reported-by: syzbot+fae49d997eb56fa7c74d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/67ea5c01.050a0220.1547ec.012b.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20250331091532.224982-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-02 16:04:19 -07:00
..
Kconfig
Makefile sctp: add fair capacity stream scheduler 2023-03-09 11:31:44 +01:00
associola.c net/sctp: Prevent autoclose integer overflow in sctp_association_init() 2024-12-23 10:10:13 -08:00
auth.c sctp: delete the nested flexible array hmac 2023-04-21 08:19:30 +01:00
bind_addr.c sctp: fail if no bound addresses can be used for a given scope 2023-01-24 18:32:33 -08:00
chunk.c
debug.c sctp: add the probe timer in transport for PLPMTUD 2021-06-22 11:28:52 -07:00
diag.c inet_diag: add module pointer to "struct inet_diag_handler" 2024-01-23 15:13:54 +01:00
endpointola.c sctp: add dif and sdif check in asoc and ep lookup 2022-11-18 11:42:54 +00:00
input.c sctp: Fix null-ptr-deref in reuseport_add_sock(). 2024-08-02 16:25:06 -07:00
inqueue.c net: sctp: fix skb leak in sctp_inq_free() 2024-02-15 07:34:52 -08:00
ipv6.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-11-14 11:29:15 -08:00
objcnt.c
offload.c net: move gso declarations and functions to their own files 2023-06-10 00:11:41 -07:00
output.c net: allow gso_max_size to exceed 65536 2022-05-16 10:18:55 +01:00
outqueue.c sctp: delete the nested flexible array variable 2023-04-21 08:19:29 +01:00
primitive.c
proc.c sctp: annotate data-races around sk->sk_wmem_queued 2023-08-31 11:56:59 +02:00
protocol.c net: use sock_kmemdup for ip_options 2025-03-03 17:16:34 -08:00
sm_make_chunk.c sctp: Spelling s/preceeding/preceding/g 2023-10-04 14:04:58 -07:00
sm_sideeffect.c sctp: handle invalid error codes without calling BUG() 2023-06-12 09:36:27 +01:00
sm_statefuns.c sctp: properly validate chunk size in sctp_sf_ootb() 2024-11-03 11:03:23 -08:00
sm_statetable.c sctp: add the probe timer in transport for PLPMTUD 2021-06-22 11:28:52 -07:00
socket.c sctp: ensure sk_state is set to CLOSED if hashing fails in sctp_listen_start 2024-10-09 13:36:32 +01:00
stream.c sctp: Fix undefined behavior in left shift operation 2025-02-19 18:55:40 -08:00
stream_interleave.c sctp: delete the nested flexible array skip 2023-04-21 08:19:29 +01:00
stream_sched.c sctp: fix a potential OOB access in sctp_sched_set_sched() 2023-05-10 12:10:15 +01:00
stream_sched_fc.c sctp: add weighted fair queueing stream scheduler 2023-03-09 11:31:44 +01:00
stream_sched_prio.c sctp: add a refcnt in sctp_stream_priorities to avoid a nested loop 2023-02-23 12:59:40 -08:00
stream_sched_rr.c sctp: delete free member from struct sctp_sched_ops 2022-12-01 20:14:23 -08:00
sysctl.c sctp: add mutual exclusion in proc_sctp_do_udp_port() 2025-04-02 16:04:19 -07:00
transport.c sctp: fix an issue that plpmtu can never go to complete state 2023-05-22 11:05:20 +01:00
tsnmap.c net: sctp: trivial: fix typo in comment 2021-03-04 13:48:32 -08:00
ulpevent.c net: remove noblock parameter from recvmsg() entities 2022-04-12 15:00:25 +02:00
ulpqueue.c sctp: remove unnecessary NULL check in sctp_ulpq_tail_event() 2022-10-20 21:43:10 -07:00