@@ -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:
@@ -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;
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> --- This patch is against 2.6.32 and should work back to 2.6.29 and probably earlier. net/core/dev.c | 11 +++++++++++ net/core/rtnetlink.c | 4 +--- 2 files changed, 12 insertions(+), 3 deletions(-)