ipv6: Assume the loopback address in link-local scope.

Handle interface property strictly when looking up a route
for the loopback address (RFC4291 2.5.3).
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

net/ipv6/route.c

@@ -228,7 +228,7 @@ static __inline__ int rt6_check_expired(const struct rt6_info *rt)
 static inline int rt6_need_strict(struct in6_addr *daddr)
 {
 	return (ipv6_addr_type(daddr) &
-		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
+		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK));
 }
 
 /*