net: Fix userspace RTM_NEWLINK notifications.

commit d90a909e1f upstream.

I received some bug reports about userspace programs having problems
because after RTM_NEWLINK was received they could not immeidate
access files under /proc/sys/net/ because they had not been
registered yet.

The problem was trivailly fixed by moving the userspace
notification from rtnetlink_event to the end of register_netdevice.

Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Eric W. Biederman
2009-12-13 22:39:28 -08:00
committed by Greg Kroah-Hartman
parent 383073d49f
commit ad496b34c6
2 changed files with 12 additions and 3 deletions

View File

@@ -4860,6 +4860,11 @@ int register_netdevice(struct net_device *dev)
rollback_registered(dev);
dev->reg_state = NETREG_UNREGISTERED;
}
/*
* Prevent userspace races by waiting until the network
* device is fully setup before sending notifications.
*/
rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
out:
return ret;
@@ -5398,6 +5403,12 @@ int dev_change_net_namespace(struct net_device *dev, struct net *net, const char
/* Notify protocols, that a new device appeared. */
call_netdevice_notifiers(NETDEV_REGISTER, dev);
/*
* Prevent userspace races by waiting until the network
* device is fully setup before sending notifications.
*/
rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
synchronize_net();
err = 0;
out:

View File

@@ -1334,13 +1334,11 @@ static int rtnetlink_event(struct notifier_block *this, unsigned long event, voi
case NETDEV_UNREGISTER:
rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
break;
case NETDEV_REGISTER:
rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
break;
case NETDEV_UP:
case NETDEV_DOWN:
rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
break;
case NETDEV_REGISTER:
case NETDEV_CHANGE:
case NETDEV_GOING_DOWN:
break;