l2tp: ensure sk->dst is still valid

When using l2tp over ipsec, the tunnel will hang when rekeying occurs. Reason is that the transformer bundle attached to the dst entry is now in STATE_DEAD and thus xfrm_output_one() drops all packets (XfrmOutStateExpired increases). Fix this by calling __sk_dst_check (which drops the stale dst if xfrm dst->check callback finds that the bundle is no longer valid). Cc: James Chapman <[email protected]> Signed-off-by: Florian Westphal <[email protected]> Acked-by: Eric Dumazet <[email protected]> Signed-off-by: David S. Miller <[email protected]>
coderetro · Nov 26, 2011 · 71b1391 · 71b1391
1 parent 8a6e77d
commit 71b1391
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
@@ -1072,7 +1072,7 @@ int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb, int hdr_len
 
 	/* Get routing info from the tunnel socket */
 	skb_dst_drop(skb);
-	skb_dst_set(skb, dst_clone(__sk_dst_get(sk)));
+	skb_dst_set(skb, dst_clone(__sk_dst_check(sk, 0)));
 
 	inet = inet_sk(sk);
 	fl = &inet->cork.fl;