act_nat: fix wild pointer
pskb_may_pull() may change skb pointers, so adjust icmph after pskb_may_pull().
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c
index 724553e..ea008f5 100644
--- a/net/sched/act_nat.c
+++ b/net/sched/act_nat.c
@@ -218,6 +218,7 @@
if (!pskb_may_pull(skb, ihl + sizeof(*icmph) + sizeof(*iph)))
goto drop;
+ icmph = (void *)(skb_network_header(skb) + ihl);
iph = (void *)(icmph + 1);
if (egress)
addr = iph->daddr;