@@ -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,
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: Nikolay Aleksandrov <nikolay@redhat.com> --- drivers/net/bonding/bond_sysfs.c | 4 ++++ 1 file changed, 4 insertions(+)