bridge: Fix inability to add non-vlan fdb entry

Bridge's default_pvid adds a vid by default, by which we cannot add a
non-vlan fdb entry by default, because br_fdb_add() adds fdb entries for
all vlans instead of a non-vlan one when any vlan is configured.

 # ip link add br0 type bridge
 # ip link set eth0 master br0
 # bridge fdb add 12:34:56:78:90:ab dev eth0 master temp
 # bridge fdb show brport eth0 | grep 12:34:56:78:90:ab
 12:34:56:78:90:ab dev eth0 vlan 1 static

We expect a non-vlan fdb entry as well as vlan 1:
 12:34:56:78:90:ab dev eth0 static

To fix this, we need to insert a non-vlan fdb entry if vlan is not
specified, even when any vlan is configured.

Fixes: 5be5a2df ("bridge: Add filtering support for default_pvid")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_fdb.c

@@ -840,10 +840,9 @@ int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 		/* VID was specified, so use it. */
 		err = __br_fdb_add(ndm, p, addr, nlh_flags, vid);
 	} else {
-		if (!pv || bitmap_empty(pv->vlan_bitmap, VLAN_N_VID)) {
 		err = __br_fdb_add(ndm, p, addr, nlh_flags, 0);
+		if (err || !pv)
 			goto out;
-		}
 
 		/* We have vlans configured on this port and user didn't
 		 * specify a VLAN.  To be nice, add/update entry for every
@@ -911,16 +910,15 @@ int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
 
 		err = __br_fdb_delete(p, addr, vid);
 	} else {
-		if (!pv || bitmap_empty(pv->vlan_bitmap, VLAN_N_VID)) {
-			err = __br_fdb_delete(p, addr, 0);
+		err = -ENOENT;
+		err &= __br_fdb_delete(p, addr, 0);
+		if (!pv)
 			goto out;
-		}
 
 		/* We have vlans configured on this port and user didn't
 		 * specify a VLAN.  To be nice, add/update entry for every
 		 * vlan on this port.
 		 */
-		err = -ENOENT;
 		for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) {
 			err &= __br_fdb_delete(p, addr, vid);
 		}