[PATCH net v2 1/3] net: bonding: Unsync device addresses on ndo_stop

[Benjamin Poirier <bpoirier@nvidia.com>]

Netdev drivers are expected to call dev_{uc,mc}_sync() in their
ndo_set_rx_mode method and dev_{uc,mc}_unsync() in their ndo_stop method.
This is mentioned in the kerneldoc for those dev_* functions.

The bonding driver calls dev_{uc,mc}_unsync() during ndo_uninit instead of
ndo_stop. This is ineffective because address lists (dev->{uc,mc}) have
already been emptied in unregister_netdevice_many() before ndo_uninit is
called. This mistake can result in addresses being leftover on former bond
slaves after a bond has been deleted; see test_LAG_cleanup() in the last
patch in this series.

Add unsync calls, via bond_hw_addr_flush(), at their expected location,
bond_close().
Add dev_mc_add() call to bond_open() to match the above change.
The existing call __bond_release_one->bond_hw_addr_flush is left in place
because there are other call chains that lead to __bond_release_one(), not
just ndo_uninit.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
---
 drivers/net/bonding/bond_main.c | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 2f4da2c13c0a..5784fbe03552 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -254,6 +254,8 @@ static const struct flow_dissector_key flow_keys_bonding_keys[] = {
 
 static struct flow_dissector flow_keys_bonding __read_mostly;
 
+static const u8 lacpdu_multicast[] = MULTICAST_LACPDU_ADDR;
+
 /*-------------------------- Forward declarations ---------------------------*/
 
 static int bond_init(struct net_device *bond_dev);
@@ -865,12 +867,8 @@ static void bond_hw_addr_flush(struct net_device *bond_dev,
 	dev_uc_unsync(slave_dev, bond_dev);
 	dev_mc_unsync(slave_dev, bond_dev);
 
-	if (BOND_MODE(bond) == BOND_MODE_8023AD) {
-		/* del lacpdu mc addr from mc list */
-		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
-
+	if (BOND_MODE(bond) == BOND_MODE_8023AD)
 		dev_mc_del(slave_dev, lacpdu_multicast);
-	}
 }
 
 /*--------------------------- Active slave change ---------------------------*/
@@ -2171,12 +2169,8 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 		dev_uc_sync_multiple(slave_dev, bond_dev);
 		netif_addr_unlock_bh(bond_dev);
 
-		if (BOND_MODE(bond) == BOND_MODE_8023AD) {
-			/* add lacpdu mc addr to mc list */
-			u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
-
+		if (BOND_MODE(bond) == BOND_MODE_8023AD)
 			dev_mc_add(slave_dev, lacpdu_multicast);
-		}
 	}
 
 	bond->slave_cnt++;
@@ -4211,6 +4205,9 @@ static int bond_open(struct net_device *bond_dev)
 		/* register to receive LACPDUs */
 		bond->recv_probe = bond_3ad_lacpdu_recv;
 		bond_3ad_initiate_agg_selection(bond, 1);
+
+		bond_for_each_slave(bond, slave, iter)
+			dev_mc_add(slave->dev, lacpdu_multicast);
 	}
 
 	if (bond_mode_can_use_xmit_hash(bond))
@@ -4222,6 +4219,7 @@ static int bond_open(struct net_device *bond_dev)
 static int bond_close(struct net_device *bond_dev)
 {
 	struct bonding *bond = netdev_priv(bond_dev);
+	struct slave *slave;
 
 	bond_work_cancel_all(bond);
 	bond->send_peer_notif = 0;
@@ -4229,6 +4227,19 @@ static int bond_close(struct net_device *bond_dev)
 		bond_alb_deinitialize(bond);
 	bond->recv_probe = NULL;
 
+	if (bond_uses_primary(bond)) {
+		rcu_read_lock();
+		slave = rcu_dereference(bond->curr_active_slave);
+		if (slave)
+			bond_hw_addr_flush(bond_dev, slave->dev);
+		rcu_read_unlock();
+	} else {
+		struct list_head *iter;
+
+		bond_for_each_slave(bond, slave, iter)
+			bond_hw_addr_flush(bond_dev, slave->dev);
+	}
+
 	return 0;
 }
 
-- 
2.37.2