sctp: fix panic when T4-rto timer expire on removed transport
If T4-rto timer is expired on a removed transport, kernel panic
will occur when we do failure management on that transport.
You can reproduce this use the following sequence:
Endpoint A Endpoint B
(ESTABLISHED) (ESTABLISHED)
<----------------- ASCONF
(SRC=X)
ASCONF ----------------->
(Delete IP Address = X)
<----------------- ASCONF-ACK
(Success Indication)
<----------------- ASCONF
(T4-rto timer expire)
This patch fixed the problem.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 3be28fe..8d3aef9 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -575,6 +575,13 @@
if (asoc->shutdown_last_sent_to == peer)
asoc->shutdown_last_sent_to = NULL;
+ /* If we remove the transport an ASCONF was last sent to, set it to
+ * NULL.
+ */
+ if (asoc->addip_last_asconf &&
+ asoc->addip_last_asconf->transport == peer)
+ asoc->addip_last_asconf->transport = NULL;
+
asoc->peer.transport_count--;
sctp_transport_free(peer);
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 10abc07..7288192 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -5475,7 +5475,9 @@
* detection on the appropriate destination address as defined in
* RFC2960 [5] section 8.1 and 8.2.
*/
- sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport));
+ if (transport)
+ sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE,
+ SCTP_TRANSPORT(transport));
/* Reconfig T4 timer and transport. */
sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk));
