Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ea6836dd authored by nikolay@redhat.com's avatar nikolay@redhat.com Committed by David S. Miller
Browse files

bonding: fix set mode race conditions 



Changing the mode without any locking can result in multiple races (e.g.
upping a bond, enslaving/releasing). Depending on which race is hit the
impact can vary from incosistent bond state to kernel crash.
Use RTNL to synchronize the mode setting with the dangerous races.

Signed-off-by: default avatarNikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ff0102ee

drivers/net/bonding/bond_sysfs.c

+4 −0
Original line number Diff line number Diff line
@@ -316,6 +316,9 @@ static ssize_t bonding_store_mode(struct device *d, 
	int new_value, ret = count;

	struct bonding *bond = to_bond(d);



	if (!rtnl_trylock())

		return restart_syscall();



	if (bond->dev->flags & IFF_UP) {

		pr_err("unable to update mode of %s because interface is up.\n",

		       bond->dev->name);
@@ -352,6 +355,7 @@ static ssize_t bonding_store_mode(struct device *d, 
		bond->dev->name, bond_mode_tbl[new_value].modename,

		new_value);

out:

	rtnl_unlock();

	return ret;

}

static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR,