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| author | Eric W. Biederman <ebiederm@xmission.com> | 2009-12-13 22:39:28 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-12-18 13:44:21 -0800 |
| commit | 0723f2f0124da4cb5ccf260bebfa703b24c199a4 (patch) | |
| tree | bf4ed258729370a8c91a5de82a5c21ed7339204c | |
| parent | 945d9a8325f6bc1f9fcb4221e5f8dab93e9e6718 (diff) | |
| download | lwn-0723f2f0124da4cb5ccf260bebfa703b24c199a4.tar.gz lwn-0723f2f0124da4cb5ccf260bebfa703b24c199a4.zip | |
net: Fix userspace RTM_NEWLINK notifications.
commit d90a909e1f3e006a1d57fe11fd417173b6494701 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>
| -rw-r--r-- | net/core/dev.c | 11 | ||||
| -rw-r--r-- | net/core/rtnetlink.c | 4 |
2 files changed, 12 insertions, 3 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 1bb5f4a8c217..42250978df88 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4808,6 +4808,11 @@ 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; @@ -5343,6 +5348,12 @@ 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: diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index d78030f88bd0..93f18454ef1d 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1347,13 +1347,11 @@ 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; |