eql: use __dev_get_by_name instead of dev_get_by_name to find interface

The following call chain indicates that eql_ioctl(), eql_enslave(),
eql_emancipate(), eql_g_slave_cfg() and eql_s_slave_cfg() are
protected under rtnl_lock. So if we use __dev_get_by_name() instead
of dev_get_by_name() to find interface handlers in them, this would
help us avoid to change interface reference counters.

dev_ioctl()
  rtnl_lock()
    dev_ifsioc()
      eql_ioctl()
        eql_enslave()
	eql_emancipate()
	eql_g_slave_cfg()
	eql_s_slave_cfg()
  rtnl_unlock()

Additionally we also change their return values from -EINVAL to
-ENODEV in case that interfaces are no found.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ying Xue 2014-01-15 10:23:38 +08:00 committed by David S. Miller
parent 0917b9334b
commit ebd93a7daf

View File

@ -395,6 +395,7 @@ static int __eql_insert_slave(slave_queue_t *queue, slave_t *slave)
if (duplicate_slave)
eql_kill_one_slave(queue, duplicate_slave);
dev_hold(slave->dev);
list_add(&slave->list, &queue->all_slaves);
queue->num_slaves++;
slave->dev->flags |= IFF_SLAVE;
@ -413,39 +414,35 @@ static int eql_enslave(struct net_device *master_dev, slaving_request_t __user *
if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
return -EFAULT;
slave_dev = dev_get_by_name(&init_net, srq.slave_name);
if (slave_dev) {
if ((master_dev->flags & IFF_UP) == IFF_UP) {
/* slave is not a master & not already a slave: */
if (!eql_is_master(slave_dev) &&
!eql_is_slave(slave_dev)) {
slave_t *s = kmalloc(sizeof(*s), GFP_KERNEL);
equalizer_t *eql = netdev_priv(master_dev);
int ret;
slave_dev = __dev_get_by_name(&init_net, srq.slave_name);
if (!slave_dev)
return -ENODEV;
if (!s) {
dev_put(slave_dev);
return -ENOMEM;
}
if ((master_dev->flags & IFF_UP) == IFF_UP) {
/* slave is not a master & not already a slave: */
if (!eql_is_master(slave_dev) && !eql_is_slave(slave_dev)) {
slave_t *s = kmalloc(sizeof(*s), GFP_KERNEL);
equalizer_t *eql = netdev_priv(master_dev);
int ret;
memset(s, 0, sizeof(*s));
s->dev = slave_dev;
s->priority = srq.priority;
s->priority_bps = srq.priority;
s->priority_Bps = srq.priority / 8;
if (!s)
return -ENOMEM;
spin_lock_bh(&eql->queue.lock);
ret = __eql_insert_slave(&eql->queue, s);
if (ret) {
dev_put(slave_dev);
kfree(s);
}
spin_unlock_bh(&eql->queue.lock);
memset(s, 0, sizeof(*s));
s->dev = slave_dev;
s->priority = srq.priority;
s->priority_bps = srq.priority;
s->priority_Bps = srq.priority / 8;
return ret;
}
spin_lock_bh(&eql->queue.lock);
ret = __eql_insert_slave(&eql->queue, s);
if (ret)
kfree(s);
spin_unlock_bh(&eql->queue.lock);
return ret;
}
dev_put(slave_dev);
}
return -EINVAL;
@ -461,24 +458,20 @@ static int eql_emancipate(struct net_device *master_dev, slaving_request_t __use
if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
return -EFAULT;
slave_dev = dev_get_by_name(&init_net, srq.slave_name);
slave_dev = __dev_get_by_name(&init_net, srq.slave_name);
if (!slave_dev)
return -ENODEV;
ret = -EINVAL;
if (slave_dev) {
spin_lock_bh(&eql->queue.lock);
if (eql_is_slave(slave_dev)) {
slave_t *slave = __eql_find_slave_dev(&eql->queue,
slave_dev);
if (slave) {
eql_kill_one_slave(&eql->queue, slave);
ret = 0;
}
spin_lock_bh(&eql->queue.lock);
if (eql_is_slave(slave_dev)) {
slave_t *slave = __eql_find_slave_dev(&eql->queue, slave_dev);
if (slave) {
eql_kill_one_slave(&eql->queue, slave);
ret = 0;
}
dev_put(slave_dev);
spin_unlock_bh(&eql->queue.lock);
}
spin_unlock_bh(&eql->queue.lock);
return ret;
}
@ -494,7 +487,7 @@ static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
return -EFAULT;
slave_dev = dev_get_by_name(&init_net, sc.slave_name);
slave_dev = __dev_get_by_name(&init_net, sc.slave_name);
if (!slave_dev)
return -ENODEV;
@ -510,8 +503,6 @@ static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
}
spin_unlock_bh(&eql->queue.lock);
dev_put(slave_dev);
if (!ret && copy_to_user(scp, &sc, sizeof (slave_config_t)))
ret = -EFAULT;
@ -529,7 +520,7 @@ static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
return -EFAULT;
slave_dev = dev_get_by_name(&init_net, sc.slave_name);
slave_dev = __dev_get_by_name(&init_net, sc.slave_name);
if (!slave_dev)
return -ENODEV;
@ -548,8 +539,6 @@ static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
}
spin_unlock_bh(&eql->queue.lock);
dev_put(slave_dev);
return ret;
}