bonding: add rtnl protection for bonding_store_fail_over_mac

We need rtnl protection while reading slave_cnt and updating
the .fail_over_mac, and it also follows the logic "don't change
anything slave-related without rtnl". :)

Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Cc: Jay Vosburgh <fubar@us.ibm.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
dingtianhong 2013-07-23 15:25:39 +08:00 committed by David S. Miller
parent 38c4916a78
commit 9402b746e7

View File

@ -501,20 +501,25 @@ static ssize_t bonding_store_fail_over_mac(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value;
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (!rtnl_trylock())
return restart_syscall();
if (bond->slave_cnt != 0) {
pr_err("%s: Can't alter fail_over_mac with slaves in bond.\n",
bond->dev->name);
return -EPERM;
ret = -EPERM;
goto out;
}
new_value = bond_parse_parm(buf, fail_over_mac_tbl);
if (new_value < 0) {
pr_err("%s: Ignoring invalid fail_over_mac value %s.\n",
bond->dev->name, buf);
return -EINVAL;
ret = -EINVAL;
goto out;
}
bond->params.fail_over_mac = new_value;
@ -522,7 +527,9 @@ static ssize_t bonding_store_fail_over_mac(struct device *d,
bond->dev->name, fail_over_mac_tbl[new_value].modename,
new_value);
return count;
out:
rtnl_unlock();
return ret;
}
static DEVICE_ATTR(fail_over_mac, S_IRUGO | S_IWUSR,