[IPSEC]: Check x->encap before dereferencing it

We need to dereference x->encap before dereferencing it for encap_type.
If it's absent then the encap_type is zero.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index e1b8f4b90d802bf430fb8ddaff53699882bba5b8..7a0b9524fe086b9e6636af41f4de4ca3f5000696 100644 (file)
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -90,7 +90,7 @@ int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
                if (unlikely(x->km.state != XFRM_STATE_VALID))
                        goto drop_unlock;
 
-               if (x->encap->encap_type != encap_type)
+               if ((x->encap ? x->encap->encap_type : 0) != encap_type)
                        goto drop_unlock;
 
                if (x->props.replay_window && xfrm_replay_check(x, seq))