xfrm: force a dst reference in __xfrm_route_forward()

Packets going through __xfrm_route_forward() have a not refcounted dst
entry, since we enabled a noref forwarding path.

xfrm_lookup() might incorrectly release this dst entry.

It's a bit late to make invasive changes in xfrm_lookup(), so lets force
a refcount in this path.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index d965a2b..4bf27d9 100644 (file)
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2153,6 +2153,7 @@ int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
                return 0;
        }
 
+       skb_dst_force(skb);
        dst = skb_dst(skb);
 
        res = xfrm_lookup(net, &dst, &fl, NULL, 0) == 0;