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>

1 files changed, 18 insertions, 2 deletions

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index b6ae60b08d46..a1429afca443 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -127,6 +127,18 @@ void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
         spin_unlock_bh(&br->hash_lock);
 }
 
+void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
+{
+        struct net_bridge_fdb_entry *f;
+
+        /* If old entry was unassociated with any port, then delete it. */
+        f = __br_fdb_get(br, br->dev->dev_addr);
+        if (f && f->is_local && !f->dst)
+                fdb_delete(br, f);
+
+        fdb_insert(br, NULL, newaddr);
+}
+
 void br_fdb_cleanup(unsigned long _data)
 {
         struct net_bridge *br = (struct net_bridge *)_data;
@@ -250,7 +262,7 @@ int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
                 ret = 0;
         else {
                 fdb = __br_fdb_get(port->br, addr);
-                ret = fdb && fdb->dst->dev != dev &&
+                ret = fdb && fdb->dst && fdb->dst->dev != dev &&
                         fdb->dst->state == BR_STATE_FORWARDING;
         }
         rcu_read_unlock();
@@ -282,6 +294,10 @@ int br_fdb_fillbuf(struct net_bridge *br, void *buf,
                         if (has_expired(br, f))
                                 continue;
 
+                        /* ignore pseudo entry for local MAC address */
+                        if (!f->dst)
+                                continue;
+
                         if (skip) {
                                 --skip;
                                 continue;
@@ -468,7 +484,7 @@ static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
         ndm->ndm_pad2    = 0;
         ndm->ndm_flags   = 0;
         ndm->ndm_type    = 0;
-        ndm->ndm_ifindex = fdb->dst->dev->ifindex;
+        ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
         ndm->ndm_state   = fdb_to_nud(fdb);
 
         NLA_PUT(skb, NDA_LLADDR, ETH_ALEN, &fdb->addr);