diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index c074771a10f761..1ca0c2f3d92bc0 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -121,7 +121,7 @@ _decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse)
 	struct flowi6 *fl6 = &fl->u.ip6;
 	int onlyproto = 0;
 	const struct ipv6hdr *hdr = ipv6_hdr(skb);
-	u16 offset = sizeof(*hdr);
+	u32 offset = sizeof(*hdr);
 	struct ipv6_opt_hdr *exthdr;
 	const unsigned char *nh = skb_network_header(skb);
 	u16 nhoff = IP6CB(skb)->nhoff;