sctp: fix panic when T2-shutdown timer expire on removed transport
If T2-shutdown 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)
<----------------- SHUTDOWN
(SRC=X)
ASCONF ----------------->
(Delete IP Address = X)
<----------------- ASCONF-ACK
(Success Indication)
<----------------- SHUTDOWN
(T2-shutdown 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 e7b69a7..3be28fe 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -567,6 +567,14 @@
if (asoc->init_last_sent_to == peer)
asoc->init_last_sent_to = NULL;
+ /* If we remove the transport an SHUTDOWN was last sent to, set it
+ * to NULL. Combined with the update of the retran path above, this
+ * will cause the next SHUTDOWN to be sent to the next available
+ * transport, maintaining the cycle.
+ */
+ if (asoc->shutdown_last_sent_to == peer)
+ asoc->shutdown_last_sent_to = NULL;
+
asoc->peer.transport_count--;
sctp_transport_free(peer);