diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index 5f983644373a..48bf5a06847b 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -130,12 +130,18 @@ _decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse)
 {
 	struct flowi6 *fl6 = &fl->u.ip6;
 	int onlyproto = 0;
-	u16 offset = skb_network_header_len(skb);
 	const struct ipv6hdr *hdr = ipv6_hdr(skb);
+	u16 offset = sizeof(*hdr);
 	struct ipv6_opt_hdr *exthdr;
 	const unsigned char *nh = skb_network_header(skb);
-	u8 nexthdr = nh[IP6CB(skb)->nhoff];
+	u16 nhoff = IP6CB(skb)->nhoff;
 	int oif = 0;
+	u8 nexthdr;
+
+	if (!nhoff)
+		nhoff = offsetof(struct ipv6hdr, nexthdr);
+
+	nexthdr = nh[nhoff];
 
 	if (skb_dst(skb))
 		oif = skb_dst(skb)->dev->ifindex;