diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 466657a..71433d2 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -430,7 +430,7 @@
 	struct rtable *rt;     			/* Route to the other host */
 	struct net_device *tdev;			/* Device to other host */
 	struct iphdr  *iph;			/* Our new IP header */
-	int    max_headroom;			/* The extra header space needed */
+	unsigned int max_headroom;		/* The extra header space needed */
 	__be32 dst = tiph->daddr;
 	int    mtu;
 	struct in6_addr *addr6;