git: 7b2f1a7fe944 - main - sctp: improve delivery of stream reset notifications

From: Michael Tuexen <tuexen_at_FreeBSD.org>
Date: Thu, 02 Feb 2023 21:44:19 UTC
The branch main has been updated by tuexen:

URL: https://cgit.FreeBSD.org/src/commit/?id=7b2f1a7fe9445ea318f34bd3db971076b61ef831

commit 7b2f1a7fe9445ea318f34bd3db971076b61ef831
Author:     Michael Tuexen <tuexen@FreeBSD.org>
AuthorDate: 2023-02-02 13:46:10 +0000
Commit:     Michael Tuexen <tuexen@FreeBSD.org>
CommitDate: 2023-02-02 13:46:10 +0000

    sctp: improve delivery of stream reset notifications
    
    Two functions are not called via sctp_ulp_notify() and therefore
    need additional checks when being called.
    
    Reported by:    syzbot+eb888d3a5a6c54413de5@syzkaller.appspotmail.com
    MFC after:      3 days
---
 sys/netinet/sctputil.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/sys/netinet/sctputil.c b/sys/netinet/sctputil.c
index 677040cd1d31..f4b6ca8c0836 100644
--- a/sys/netinet/sctputil.c
+++ b/sys/netinet/sctputil.c
@@ -3815,10 +3815,17 @@ sctp_notify_stream_reset_add(struct sctp_tcb *stcb, uint16_t numberin, uint16_t
 	struct sctp_stream_change_event *stradd;
 
 	if ((stcb == NULL) ||
-	    (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_STREAM_CHANGEEVNT))) {
+	    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
+	    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
+	    (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)) {
+		/* If the socket is gone we are out of here. */
+		return;
+	}
+	if (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_STREAM_CHANGEEVNT)) {
 		/* event not enabled */
 		return;
 	}
+
 	if ((stcb->asoc.peer_req_out) && flag) {
 		/* Peer made the request, don't tell the local user */
 		stcb->asoc.peer_req_out = 0;
@@ -3871,10 +3878,17 @@ sctp_notify_stream_reset_tsn(struct sctp_tcb *stcb, uint32_t sending_tsn, uint32
 	struct sctp_assoc_reset_event *strasoc;
 
 	if ((stcb == NULL) ||
-	    (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_ASSOC_RESETEVNT))) {
+	    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_GONE) ||
+	    (stcb->sctp_ep->sctp_flags & SCTP_PCB_FLAGS_SOCKET_ALLGONE) ||
+	    (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET)) {
+		/* If the socket is gone we are out of here. */
+		return;
+	}
+	if (sctp_stcb_is_feature_off(stcb->sctp_ep, stcb, SCTP_PCB_FLAGS_ASSOC_RESETEVNT)) {
 		/* event not enabled */
 		return;
 	}
+
 	m_notify = sctp_get_mbuf_for_msg(sizeof(struct sctp_assoc_reset_event), 0, M_NOWAIT, 1, MT_DATA);
 	if (m_notify == NULL)
 		/* no space left */