bridge: add local MAC address to forwarding table (v2)

If user has configured a MAC address that is not one of the existing
ports of the bridge, then we need to add a special entry in the forwarding
table. This forwarding table entry has no outgoing port so it has to be
treated a little differently. The special entry is reported by the netlink
interface with ifindex of bridge, but ignored by the old interface since there
is no usable way to put it in the ABI.

Reported-by: Koki Sanagi <sanagi.koki@jp.fujitsu.com>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c
index ee64287..61f6534 100644
--- a/net/bridge/br_forward.c
+++ b/net/bridge/br_forward.c
@@ -98,7 +98,7 @@
 /* called with rcu_read_lock */
 void br_deliver(const struct net_bridge_port *to, struct sk_buff *skb)
 {
-	if (should_deliver(to, skb)) {
+	if (to && should_deliver(to, skb)) {
 		__br_deliver(to, skb);
 		return;
 	}