bridge: Change local fdb entries whenever mac address of bridge device changes (a4b816d8) · Commits · 戴 / test

Vlan code may need fdb change when changing mac address of bridge device even if it is caused by the mac address changing of a bridge port. Example configuration: ip link set eth0 address 12:34:56:78:90:ab ip link set eth1 address aa:bb:cc:dd:ee:ff brctl addif br0 eth0 brctl addif br0 eth1 # br0 will have mac address 12:34:56:78:90:ab bridge vlan add dev br0 vid 10 self bridge vlan add dev eth0 vid 10 We will have fdb entry such that f->dst == NULL, f->vlan_id == 10 and f->addr == 12:34:56:78:90:ab at this time. Next, change the mac address of eth0 to greater value. ip link set eth0 address ee:ff:12:34:56:78 Then, mac address of br0 will be recalculated and set to aa:bb:cc:dd:ee:ff. However, an entry aa:bb:cc:dd:ee:ff will not be created and we will be not able to communicate using br0 on vlan 10. Address this issue by deleting and adding local entries whenever changing the mac address of the bridge device. If there already exists an entry that has the same address, for example, in case that br_fdb_changeaddr() has already inserted it, br_fdb_change_mac_address() will simply fail to insert it and no duplicated entry will be made, as it was. This approach also needs br_add_if() to call br_fdb_insert() before br_stp_recalculate_bridge_id() so that we don't create an entry whose dst == NULL in this function to preserve previous behavior. Note that this is a slight change in behavior where the bridge device can receive the traffic to the new address before calling br_stp_recalculate_bridge_id() in br_add_if(). However, it is not a problem because we have already the address on the new port and such a way to insert new one before recalculating bridge id is taken in br_device_event() as well. 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_device.c

+0 −1

Original line number	Original line	Diff line number	Diff line
	@@ -187,7 +187,6 @@ static int br_set_mac_address(struct net_device dev, void p)

	spin_lock_bh(&br->lock);		spin_lock_bh(&br->lock);
	if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) {		if (!ether_addr_equal(dev->dev_addr, addr->sa_data)) {
	br_fdb_change_mac_address(br, addr->sa_data);
	/* Mac address will be changed in br_stp_change_bridge_id(). */		/* Mac address will be changed in br_stp_change_bridge_id(). */
	br_stp_change_bridge_id(br, addr->sa_data);		br_stp_change_bridge_id(br, addr->sa_data);
	}		}

net/bridge/br_if.c

+3 −3

Original line number	Original line	Diff line number	Diff line
	@@ -389,6 +389,9 @@ int br_add_if(struct net_bridge br, struct net_device dev)
	if (br->dev->needed_headroom < dev->needed_headroom)		if (br->dev->needed_headroom < dev->needed_headroom)
	br->dev->needed_headroom = dev->needed_headroom;		br->dev->needed_headroom = dev->needed_headroom;

			if (br_fdb_insert(br, p, dev->dev_addr, 0))
			netdev_err(dev, "failed insert local address bridge forwarding table\n");

	spin_lock_bh(&br->lock);		spin_lock_bh(&br->lock);
	changed_addr = br_stp_recalculate_bridge_id(br);		changed_addr = br_stp_recalculate_bridge_id(br);

	@@ -404,9 +407,6 @@ int br_add_if(struct net_bridge br, struct net_device dev)

	dev_set_mtu(br->dev, br_min_mtu(br));		dev_set_mtu(br->dev, br_min_mtu(br));

	if (br_fdb_insert(br, p, dev->dev_addr, 0))
	netdev_err(dev, "failed insert local address bridge forwarding table\n");

	kobject_uevent(&p->kobj, KOBJ_ADD);		kobject_uevent(&p->kobj, KOBJ_ADD);

	return 0;		return 0;

net/bridge/br_stp_if.c

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -194,6 +194,8 @@ void br_stp_change_bridge_id(struct net_bridge br, const unsigned char addr)

	wasroot = br_is_root_bridge(br);		wasroot = br_is_root_bridge(br);

			br_fdb_change_mac_address(br, addr);

	memcpy(oldaddr, br->bridge_id.addr, ETH_ALEN);		memcpy(oldaddr, br->bridge_id.addr, ETH_ALEN);
	memcpy(br->bridge_id.addr, addr, ETH_ALEN);		memcpy(br->bridge_id.addr, addr, ETH_ALEN);
	memcpy(br->dev->dev_addr, addr, ETH_ALEN);		memcpy(br->dev->dev_addr, addr, ETH_ALEN);

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