This patch fixes an address scope violation. Considering the

scenario where an anycast address is assigned on one interface,
and a global address with the same scope is assigned on another
interface. In other words, the interface owns the anycast
address has only the link-local address as one other address.
Without this patch, "ping6" the anycast address from another
station will observe the source address of the returned ICMP6
echo reply has the link-local address, not the global address
that exists on the other interface in the same node.

Reviewed by:	bz
MFC after:	immediately

sys/netinet6/icmp6.c

@@ -2170,6 +2170,10 @@ icmp6_reflect(struct mbuf *m, size_t off)
 		}
 	}
 
+	if ((srcp != NULL) && 
+	    (in6_addrscope(srcp) != in6_addrscope(&ip6->ip6_src)))
+		srcp = NULL;
+
 	if (srcp == NULL) {
 		int e;
 		struct sockaddr_in6 sin6;