From adfb7f807c662a69afc0b775ccf070cfab04aac5 Mon Sep 17 00:00:00 2001 From: Mark Johnston Date: Thu, 9 Sep 2021 08:33:26 -0400 Subject: [PATCH] sctp: Clear assoc socket references when freeing a PCB This restores behaviour present in the first import of SCTP. Commit ceaad40ae729dea2c5d8ffcfdd45bb96fb8969d2 commented this out and commit 62fb761ff28bb184a2543e539dd689fefd5d3246 removed it. However, once sctp_inpcb_free() returns, the socket reference is gone no matter what, so we need to clear it. Reported by: syzbot+30dd69297fcbc5f0e10a@syzkaller.appspotmail.com Reported by: syzbot+7b2f9d4bcac1c9569291@syzkaller.appspotmail.com Reported by: syzbot+ed3e651f7d040af480a6@syzkaller.appspotmail.com Reviewed by: tuexen Sponsored by: The FreeBSD Foundation (cherry picked from commit 4250aa1188b5622a6cef871003abd4a50067bdae) --- sys/netinet/sctp_pcb.c | 1 + 1 file changed, 1 insertion(+) diff --git a/sys/netinet/sctp_pcb.c b/sys/netinet/sctp_pcb.c index 85ea5a3f8a5..7e0c0562e8a 100644 --- a/sys/netinet/sctp_pcb.c +++ b/sys/netinet/sctp_pcb.c @@ -3359,6 +3359,7 @@ sctp_inpcb_free(struct sctp_inpcb *inp, int immediate, int from) LIST_FOREACH_SAFE(asoc, &inp->sctp_asoc_list, sctp_tcblist, nasoc) { SCTP_TCB_LOCK(asoc); if (asoc->asoc.state & SCTP_STATE_ABOUT_TO_BE_FREED) { + asoc->sctp_socket = NULL; /* Skip guys being freed */ cnt_in_sd++; if (asoc->asoc.state & SCTP_STATE_IN_ACCEPT_QUEUE) {