net: Fix userspace RTM_NEWLINK notifications.
I received some bug reports about userspace programs having problems
because after RTM_NEWLINK was received they could not immediate access
files under /proc/sys/net/ because they had not been registered yet.
The original problem was trivially fixed by moving the userspace
notification from rtnetlink_event() to the end of
register_netdevice().
When testing that change I discovered I was still getting RTM_NEWLINK
events before I could access proc and I was also getting RTM_NEWLINK
events after I was seeing RTM_DELLINK. Things practically guaranteed
to confuse userspace.
After a little more investigation these extra notifications proved to
be from the new notifiers NETDEV_POST_INIT and NETDEV_UNREGISTER_BATCH
hitting the default case in rtnetlink_event, and triggering
unnecessary RTM_NEWLINK messages.
rtnetlink_event now explicitly handles NETDEV_UNREGISTER_BATCH and
NETDEV_POST_INIT to avoid sending the incorrect userspace
notifications.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 33148a5..794bcb8 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1364,15 +1364,15 @@
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_POST_INIT:
+ case NETDEV_REGISTER:
case NETDEV_CHANGE:
case NETDEV_GOING_DOWN:
+ case NETDEV_UNREGISTER_BATCH:
break;
default:
rtmsg_ifinfo(RTM_NEWLINK, dev, 0);