bridge: Properly check if local fdb entry can be deleted in br_fdb_delete_by_port

br_fdb_delete_by_port() doesn't care about vlan and mac address of the
bridge device.

As the check is almost the same as mac address changing, slightly modify
fdb_delete_local() and use it.

Note that we can always set added_by_user to 0 in fdb_delete_local() because
- br_fdb_delete_by_port() calls fdb_delete_local() for local entries
  regardless of its added_by_user. In this case, we have to check if another
  port has the same address and vlan, and if found, we have to create the
  entry (by changing dst). This is kernel-added entry, not user-added.
- br_fdb_changeaddr() doesn't call fdb_delete_local() for user-added entry.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_fdb.c

@@ -103,6 +103,7 @@ static void fdb_delete_local(struct net_bridge *br,
 		if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
 		    (!vid || nbp_vlan_find(op, vid))) {
 			f->dst = op;
+			f->added_by_user = 0;
 			return;
 		}
 	}
@@ -111,6 +112,7 @@ static void fdb_delete_local(struct net_bridge *br,
 	if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
 	    (!vid || br_vlan_find(br, vid))) {
 		f->dst = NULL;
+		f->added_by_user = 0;
 		return;
 	}
 
@@ -261,26 +263,11 @@ void br_fdb_delete_by_port(struct net_bridge *br,
 
 			if (f->is_static && !do_all)
 				continue;
-			/*
-			 * if multiple ports all have the same device address
-			 * then when one port is deleted, assign
-			 * the local entry to other port
-			 */
-			if (f->is_local) {
-				struct net_bridge_port *op;
-				list_for_each_entry(op, &br->port_list, list) {
-					if (op != p &&
-					    ether_addr_equal(op->dev->dev_addr,
-							     f->addr.addr)) {
-						f->dst = op;
-						f->added_by_user = 0;
-						goto skip_delete;
-					}
-				}
-			}
 
-			fdb_delete(br, f);
-		skip_delete: ;
+			if (f->is_local)
+				fdb_delete_local(br, p, f);
+			else
+				fdb_delete(br, f);
 		}
 	}
 	spin_unlock_bh(&br->hash_lock);