Merge branch 'linus' into core/softlockup

1 files changed, 13 insertions, 0 deletions

diff --git a/net/sctp/input.c b/net/sctp/input.c
index bf612d954d41..2e4a8646dbc3 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -249,6 +249,19 @@ int sctp_rcv(struct sk_buff *skb)
          */
         sctp_bh_lock_sock(sk);
 
+        if (sk != rcvr->sk) {
+                /* Our cached sk is different from the rcvr->sk.  This is
+                 * because migrate()/accept() may have moved the association
+                 * to a new socket and released all the sockets.  So now we
+                 * are holding a lock on the old socket while the user may
+                 * be doing something with the new socket.  Switch our veiw
+                 * of the current sk.
+                 */
+                sctp_bh_unlock_sock(sk);
+                sk = rcvr->sk;
+                sctp_bh_lock_sock(sk);
+        }
+
         if (sock_owned_by_user(sk)) {
                 SCTP_INC_STATS_BH(SCTP_MIB_IN_PKT_BACKLOG);
                 sctp_add_backlog(sk, skb);