linux/net/sctp
Xin Long 165e3e17fe 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: 7b9438de0c ("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>
2022-04-23 22:34:17 +01:00
..
associola.c sctp: enable PLPMTUD when the transport is ready 2021-06-22 11:28:52 -07:00
auth.c sctp: move the active_key update after sh_keys is added 2021-08-03 11:43:43 +01:00
bind_addr.c sctp: validate from_addr_param return 2021-06-28 15:34:50 -07:00
chunk.c net: sctp: chunk.c: delete duplicated word 2020-08-24 16:21:43 -07:00
debug.c sctp: add the probe timer in transport for PLPMTUD 2021-06-22 11:28:52 -07:00
diag.c sctp: fix kernel-infoleak for SCTP sockets 2022-03-10 14:46:42 -08:00
endpointola.c sctp: use call_rcu to free endpoint 2021-12-25 17:13:37 +00:00
input.c sctp: move hlist_node and hashent out of sctp_ep_common 2021-12-23 11:15:30 +00:00
inqueue.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
ipv6.c sctp: delete addr based on sin6_scope_id 2021-07-26 12:34:03 +01:00
Kconfig sctp: create udp4 sock and add its encap_rcv 2020-10-30 15:23:52 -07:00
Makefile sctp: rename sctp_diag.c as diag.c 2018-02-13 13:56:31 -05:00
objcnt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
offload.c sctp: remove the NETIF_F_SG flag before calling skb_segment 2021-01-16 19:05:59 -08:00
output.c net: annotate accesses to dev->gso_max_size 2021-11-22 12:49:42 +00:00
outqueue.c sctp: count singleton chunks in assoc user stats 2022-04-05 09:51:12 +02:00
primitive.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
proc.c sctp: move hlist_node and hashent out of sctp_ep_common 2021-12-23 11:15:30 +00:00
protocol.c include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.h 2021-11-06 13:30:43 -07:00
sm_make_chunk.c sctp: account stream padding length for reconf chunk 2021-10-14 07:15:22 -07:00
sm_sideeffect.c sctp: check asoc strreset_chunk in sctp_generate_reconf_event 2022-04-23 22:34:17 +01:00
sm_statefuns.c sctp: use the correct skb for security_sctp_assoc_request 2022-04-08 14:38:58 -07:00
sm_statetable.c sctp: add the probe timer in transport for PLPMTUD 2021-06-22 11:28:52 -07:00
socket.c sctp: Initialize daddr on peeled off socket 2022-04-11 20:33:10 -07:00
stream_interleave.c sctp: get netns from asoc and ep base 2019-12-09 20:14:01 -08:00
stream_sched_prio.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
stream_sched_rr.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104 2019-05-24 17:39:00 +02:00
stream_sched.c sctp: rename asoc intl_enable to asoc peer.intl_capable 2019-07-08 20:16:25 -07:00
stream.c net: sctp: Fix negotiation of the number of data streams. 2020-08-20 16:37:37 -07:00
sysctl.c sctp: add probe_interval in sysctl and sock/asoc/transport 2021-06-22 11:28:51 -07:00
transport.c sctp: make the raise timer more simple and accurate 2021-11-25 21:00:45 -08:00
tsnmap.c net: sctp: trivial: fix typo in comment 2021-03-04 13:48:32 -08:00
ulpevent.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-31 17:48:46 -07:00
ulpqueue.c net: sctp: ulpqueue.c: delete duplicated word 2020-08-24 16:21:43 -07:00