net/sctp: Prevent autoclose integer overflow in sctp_association_init()

JIRA: https://issues.redhat.com/browse/RHEL-73625
Tested: compile only

commit 4e86729
Author: Nikolay Kuratov <kniv@yandex-team.ru>
Date:   Thu Dec 19 19:21:14 2024 +0300

    net/sctp: Prevent autoclose integer overflow in sctp_association_init()

    While by default max_autoclose equals to INT_MAX / HZ, one may set
    net.sctp.max_autoclose to UINT_MAX. There is code in
    sctp_association_init() that can consequently trigger overflow.

    Cc: stable@vger.kernel.org
    Fixes: 9f70f46 ("sctp: properly latch and use autoclose value from sock to association")
    Signed-off-by: Nikolay Kuratov <kniv@yandex-team.ru>
    Acked-by: Xin Long <lucien.xin@gmail.com>
    Link: https://patch.msgid.link/20241219162114.2863827-1-kniv@yandex-team.ru
    Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Signed-off-by: Xin Long <lxin@redhat.com>

Author: Xin Long

net/sctp/associola.c

@@ -137,7 +137,8 @@ static struct sctp_association *sctp_association_init(
 		= 5 * asoc->rto_max;
 
 	asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
-	asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sp->autoclose * HZ;
+	asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] =
+		(unsigned long)sp->autoclose * HZ;
 
 	/* Initializes the timers */
 	for (i = SCTP_EVENT_TIMEOUT_NONE; i < SCTP_NUM_TIMEOUT_TYPES; ++i)