From 745db35452567cca10e92a2b0c70d85494c1ad0e Mon Sep 17 00:00:00 2001 From: Mahesh Bandewar Date: Thu, 1 Sep 2016 22:18:34 -0700 Subject: bonding: Fix bonding crash commit 24b27fc4cdf9e10c5e79e5923b6b7c2c5c95096c upstream. Following few steps will crash kernel - (a) Create bonding master > modprobe bonding miimon=50 (b) Create macvlan bridge on eth2 > ip link add link eth2 dev mvl0 address aa:0:0:0:0:01 \ type macvlan (c) Now try adding eth2 into the bond > echo +eth2 > /sys/class/net/bond0/bonding/slaves Bonding does lots of things before checking if the device enslaved is busy or not. In this case when the notifier call-chain sends notifications, the bond_netdev_event() assumes that the rx_handler /rx_handler_data is registered while the bond_enslave() hasn't progressed far enough to register rx_handler for the new slave. This patch adds a rx_handler check that can be performed right at the beginning of the enslave code to avoid getting into this situation. Signed-off-by: Mahesh Bandewar Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Willy Tarreau --- drivers/net/bonding/bond_main.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index c0ed7c802819..ce41616d9d1a 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1565,9 +1565,10 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev) bond_dev->name, slave_dev->name); } - /* already enslaved */ - if (slave_dev->flags & IFF_SLAVE) { - pr_debug("Error, Device was already enslaved\n"); + /* already in-use? */ + if (netdev_is_rx_handler_busy(slave_dev)) { + netdev_err(bond_dev, + "Error: Device is in use and cannot be enslaved\n"); return -EBUSY; } -- cgit v1.2.3