net/bonding: Fix potential bad memory access during bonding events

When queuing work to send the NETDEV_BONDING_INFO netdev event, it's
possible that when the work is executed, the pointer to the slave
becomes invalid. This can happen if between queuing the event and the
execution of the work, the net-device was un-ensvaled and re-enslaved.

Fix that by queuing a work with the data of the slave instead of the
slave structure.

Fixes: 69e6113343 ('net/bonding: Notify state change on slaves')
Reported-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Moni Shoua 2015-02-08 11:49:32 +02:00 committed by David S. Miller
parent 9dce285b70
commit 92e584fe44
2 changed files with 12 additions and 18 deletions

View File

@ -1196,18 +1196,11 @@ static void bond_fill_ifslave(struct slave *slave, struct ifslave *info)
info->link_failure_count = slave->link_failure_count;
}
static void bond_netdev_notify(struct slave *slave, struct net_device *dev)
static void bond_netdev_notify(struct net_device *dev,
struct netdev_bonding_info *info)
{
struct bonding *bond = slave->bond;
struct netdev_bonding_info bonding_info;
rtnl_lock();
/* make sure that slave is still valid */
if (dev->priv_flags & IFF_BONDING) {
bond_fill_ifslave(slave, &bonding_info.slave);
bond_fill_ifbond(bond, &bonding_info.master);
netdev_bonding_info_change(slave->dev, &bonding_info);
}
netdev_bonding_info_change(dev, info);
rtnl_unlock();
}
@ -1216,25 +1209,26 @@ static void bond_netdev_notify_work(struct work_struct *_work)
struct netdev_notify_work *w =
container_of(_work, struct netdev_notify_work, work.work);
bond_netdev_notify(w->slave, w->dev);
bond_netdev_notify(w->dev, &w->bonding_info);
dev_put(w->dev);
kfree(w);
}
void bond_queue_slave_event(struct slave *slave)
{
struct bonding *bond = slave->bond;
struct netdev_notify_work *nnw = kzalloc(sizeof(*nnw), GFP_ATOMIC);
if (!nnw)
return;
INIT_DELAYED_WORK(&nnw->work, bond_netdev_notify_work);
nnw->slave = slave;
dev_hold(slave->dev);
nnw->dev = slave->dev;
bond_fill_ifslave(slave, &nnw->bonding_info.slave);
bond_fill_ifbond(bond, &nnw->bonding_info.master);
INIT_DELAYED_WORK(&nnw->work, bond_netdev_notify_work);
if (queue_delayed_work(slave->bond->wq, &nnw->work, 0))
dev_hold(slave->dev);
else
kfree(nnw);
queue_delayed_work(slave->bond->wq, &nnw->work, 0);
}
/* enslave device <slave> to bond device <master> */

View File

@ -152,8 +152,8 @@ struct bond_parm_tbl {
struct netdev_notify_work {
struct delayed_work work;
struct slave *slave;
struct net_device *dev;
struct netdev_bonding_info bonding_info;
};
struct slave {