rtnetlink: call ->dellink on failure when ->newlink exists

Ignacy reported that when eth0 is down and add a vlan device
on top of it like:

  ip link add link eth0 name eth0.1 up type vlan id 1

We will get a refcount leak:

  unregister_netdevice: waiting for eth0.1 to become free. Usage count = 2

The problem is when rtnl_configure_link() fails in rtnl_newlink(),
we simply call unregister_device(), but for stacked device like vlan,
we almost do nothing when we unregister the upper device, more work
is done when we unregister the lower device, so call its ->dellink().

Reported-by: Ignacy Gawedzki <ignacy.gawedzki@green-communications.fr>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
WANG Cong 2015-02-13 13:56:53 -08:00 committed by David S. Miller
parent d95e2fe0ff
commit 7afb8886a0
1 changed files with 8 additions and 1 deletions

View File

@ -2162,7 +2162,14 @@ replay:
}
err = rtnl_configure_link(dev, ifm);
if (err < 0) {
unregister_netdevice(dev);
if (ops->newlink) {
LIST_HEAD(list_kill);
ops->dellink(dev, &list_kill);
unregister_netdevice_many(&list_kill);
} else {
unregister_netdevice(dev);
}
goto out;
}