bonding: fix two race conditions in bond_store_updelay/downdelay

This patch fixes two race conditions between bond_store_updelay/downdelay
and bond_store_miimon which could lead to division by zero as miimon can
be set to 0 while either updelay/downdelay are being set and thus miss the
zero check in the beginning, the zero div happens because updelay/downdelay
are stored as new_value / bond->params.miimon. Use rtnl to synchronize with
miimon setting.

CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Nikolay Aleksandrov 2013-11-13 17:07:46 +01:00 committed by David S. Miller
parent 98e09386c0
commit b869ccfab1

View File

@ -702,6 +702,8 @@ static ssize_t bonding_store_downdelay(struct device *d,
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (!rtnl_trylock())
return restart_syscall();
if (!(bond->params.miimon)) {
pr_err("%s: Unable to set down delay as MII monitoring is disabled\n",
bond->dev->name);
@ -735,6 +737,7 @@ static ssize_t bonding_store_downdelay(struct device *d,
}
out:
rtnl_unlock();
return ret;
}
static DEVICE_ATTR(downdelay, S_IRUGO | S_IWUSR,
@ -757,6 +760,8 @@ static ssize_t bonding_store_updelay(struct device *d,
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (!rtnl_trylock())
return restart_syscall();
if (!(bond->params.miimon)) {
pr_err("%s: Unable to set up delay as MII monitoring is disabled\n",
bond->dev->name);
@ -790,6 +795,7 @@ static ssize_t bonding_store_updelay(struct device *d,
}
out:
rtnl_unlock();
return ret;
}
static DEVICE_ATTR(updelay, S_IRUGO | S_IWUSR,