diff --git a/include/net/protocol.h b/include/net/protocol.h
index 28c4cac3f8a2733b9f582cc3be1b9bc591022c21..105bf12b0c79588c6e45bf55239dc1bd6a1c27e2 100644
--- a/include/net/protocol.h
+++ b/include/net/protocol.h
@@ -71,7 +71,7 @@ struct inet_protosw {
 
         /* These two fields form the lookup key.  */
 	unsigned short	 type;	   /* This is the 2nd argument to socket(2). */
-	int		 protocol; /* This is the L4 protocol number.  */
+	unsigned short	 protocol; /* This is the L4 protocol number.  */
 
 	struct proto	 *prot;
 	const struct proto_ops *ops;