[SCTP]: Fix potential race condition between sctp_close() and sctp_rcv().
Do not release the reference to association/endpoint if an incoming skb is
added to backlog. Instead release it after the chunk is processed in
sctp_backlog_rcv().
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 4aa6fc6..c463e404 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -262,15 +262,12 @@
else
sctp_backlog_rcv(sk, skb);
- /* Release the sock and any reference counts we took in the
- * lookup calls.
+ /* Release the sock and the sock ref we took in the lookup calls.
+ * The asoc/ep ref will be released in sctp_backlog_rcv.
*/
sctp_bh_unlock_sock(sk);
- if (asoc)
- sctp_association_put(asoc);
- else
- sctp_endpoint_put(ep);
sock_put(sk);
+
return ret;
discard_it:
@@ -296,9 +293,23 @@
int sctp_backlog_rcv(struct sock *sk, struct sk_buff *skb)
{
struct sctp_chunk *chunk = SCTP_INPUT_CB(skb)->chunk;
- struct sctp_inq *inqueue = &chunk->rcvr->inqueue;
+ struct sctp_inq *inqueue = NULL;
+ struct sctp_ep_common *rcvr = NULL;
- sctp_inq_push(inqueue, chunk);
+ rcvr = chunk->rcvr;
+ if (rcvr->dead) {
+ sctp_chunk_free(chunk);
+ } else {
+ inqueue = &chunk->rcvr->inqueue;
+ sctp_inq_push(inqueue, chunk);
+ }
+
+ /* Release the asoc/ep ref we took in the lookup calls in sctp_rcv. */
+ if (SCTP_EP_TYPE_ASSOCIATION == rcvr->type)
+ sctp_association_put(sctp_assoc(rcvr));
+ else
+ sctp_endpoint_put(sctp_ep(rcvr));
+
return 0;
}
diff --git a/net/sctp/inqueue.c b/net/sctp/inqueue.c
index 2d33922..297b895 100644
--- a/net/sctp/inqueue.c
+++ b/net/sctp/inqueue.c
@@ -73,8 +73,10 @@
/* If there is a packet which is currently being worked on,
* free it as well.
*/
- if (queue->in_progress)
+ if (queue->in_progress) {
sctp_chunk_free(queue->in_progress);
+ queue->in_progress = NULL;
+ }
if (queue->malloced) {
/* Dump the master memory segment. */
