tcp: force a dst refcount when prequeue packet
[ Upstream commit 093162553c33e9479283e107b4431378271c735d ]
Before escaping RCU protected section and adding packet into
prequeue, make sure the dst is refcounted.
Reported-by: Mike Galbraith <bitbucket@online.de>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 2757a11..8376a6a 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -948,6 +948,7 @@
if (sysctl_tcp_low_latency || !tp->ucopy.task)
return 0;
+ skb_dst_force(skb);
__skb_queue_tail(&tp->ucopy.prequeue, skb);
tp->ucopy.memory += skb->truesize;
if (tp->ucopy.memory > sk->sk_rcvbuf) {