Use dhcp-range tags when replying to DHCPv6 information-request.

src/rfc3315.c

@@ -1010,6 +1010,13 @@ static int dhcp6_no_relay(int msg_type, struct in6_addr *link_address, struct dh
       
     case DHCP6IREQ:
       {
+	/* We can't discriminate contexts based on address, as we don't know it.
+	   If there is only one possible context, we can use its tags */
+	if (context && !context->current)
+	  {
+	    context->netid.next = NULL;
+	    context_tags =  &context->netid;
+	  }
 	log6_packet("DHCPINFORMATION-REQUEST", clid, clid_len, NULL, xid, iface_name, ignore ? "ignored" : hostname);
 	if (ignore)
 	  return 0;