Commit 5e1eee55 authored by Xin Long's avatar Xin Long Committed by Wang Liang
Browse files

sctp: set sk_state back to CLOSED if autobind fails in sctp_listen_start 

stable inclusion
from stable-v5.10.227
commit dd70c8a89ef99c3d53127fe19e51ef47c3f860fa
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYRCU
CVE: CVE-2024-49944

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=dd70c8a89ef99c3d53127fe19e51ef47c3f860fa



--------------------------------

[ Upstream commit 8beee4d8dee76b67c75dc91fd8185d91e845c160 ]

In sctp_listen_start() invoked by sctp_inet_listen(), it should set the
sk_state back to CLOSED if sctp_autobind() fails due to whatever reason.

Otherwise, next time when calling sctp_inet_listen(), if sctp_sk(sk)->reuse
is already set via setsockopt(SCTP_REUSE_PORT), sctp_sk(sk)->bind_hash will
be dereferenced as sk_state is LISTENING, which causes a crash as bind_hash
is NULL.

  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
  RIP: 0010:sctp_inet_listen+0x7f0/0xa20 net/sctp/socket.c:8617
  Call Trace:
   <TASK>
   __sys_listen_socket net/socket.c:1883 [inline]
   __sys_listen+0x1b7/0x230 net/socket.c:1894
   __do_sys_listen net/socket.c:1902 [inline]

Fixes: 5e8f3f70 ("sctp: simplify sctp listening code")
Reported-by: default avatar <syzbot+f4e0f821e3a3b7cee51d@syzkaller.appspotmail.com>
Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Acked-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://patch.msgid.link/a93e655b3c153dc8945d7a812e6d8ab0d52b7aa0.1727729391.git.lucien.xin@gmail.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarWang Liang <wangliang74@huawei.com>
parent 1a47bbfa

net/sctp/socket.c

+3 −1
Original line number Diff line number Diff line
@@ -8282,8 +8282,10 @@ static int sctp_listen_start(struct sock *sk, int backlog) 
	 */

	inet_sk_set_state(sk, SCTP_SS_LISTENING);

	if (!ep->base.bind_addr.port) {

		if (sctp_autobind(sk))

		if (sctp_autobind(sk)) {

			inet_sk_set_state(sk, SCTP_SS_CLOSED);

			return -EAGAIN;

		}

	} else {

		if (sctp_get_port(sk, inet_sk(sk)->inet_num)) {

			inet_sk_set_state(sk, SCTP_SS_CLOSED);