bridge: Fix the way to insert new local fdb entries in br_fdb_changeaddr

Since commit bc9a25d21ef8 ("bridge: Add vlan support for local fdb entries"),
br_fdb_changeaddr() has inserted a new local fdb entry only if it can
find old one. But if we have two ports where they have the same address
or user has deleted a local entry, there will be no entry for one of the
ports.

Example of problematic case:
  ip link set eth0 address aa:bb:cc:dd:ee:ff
  ip link set eth1 address aa:bb:cc:dd:ee:ff
  brctl addif br0 eth0
  brctl addif br0 eth1 # eth1 will not have a local entry due to dup.
  ip link set eth1 address 12:34:56:78:90:ab
Then, the new entry for the address 12:34:56:78:90:ab will not be
created, and the bridge device will not be able to communicate.

Insert new entries regardless of whether we can find old entries or not.

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>

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index ce54119..96ab1d1 100644 (file)
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -92,8 +92,10 @@ static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f)
 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
 {
        struct net_bridge *br = p->br;
-       bool no_vlan = (nbp_get_vlan_info(p) == NULL) ? true : false;
+       struct net_port_vlans *pv = nbp_get_vlan_info(p);
+       bool no_vlan = !pv;
        int i;
+       u16 vid;
 
        spin_lock_bh(&br->hash_lock);
 
@@ -114,28 +116,37 @@ void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
                                                             f->addr.addr) &&
                                            nbp_vlan_find(op, vid)) {
                                                f->dst = op;
-                                               goto insert;
+                                               goto skip_delete;
                                        }
                                }
 
                                /* delete old one */
                                fdb_delete(br, f);
-insert:
-                               /* insert new address,  may fail if invalid
-                                * address or dup.
-                                */
-                               fdb_insert(br, p, newaddr, vid);
-
+skip_delete:
                                /* if this port has no vlan information
                                 * configured, we can safely be done at
                                 * this point.
                                 */
                                if (no_vlan)
-                                       goto done;
+                                       goto insert;
                        }
                }
        }
 
+insert:
+       /* insert new address,  may fail if invalid address or dup. */
+       fdb_insert(br, p, newaddr, 0);
+
+       if (no_vlan)
+               goto done;
+
+       /* Now add entries for every VLAN configured on the port.
+        * This function runs under RTNL so the bitmap will not change
+        * from under us.
+        */
+       for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID)
+               fdb_insert(br, p, newaddr, vid);
+
 done:
        spin_unlock_bh(&br->hash_lock);
 }