[NET]: Make device event notification network namespace safe

Every user of the network device notifiers is either a protocol
stack or a pseudo device.  If a protocol stack that does not have
support for multiple network namespaces receives an event for a
device that is not in the initial network namespace it quite possibly
can get confused and do the wrong thing.

To avoid problems until all of the protocol stacks are converted
this patch modifies all netdev event handlers to ignore events on
devices that are not in the initial network namespace.

As the rest of the code is made network namespace aware these
checks can be removed.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 9 insertions, 0 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index cd2db728d18..1a678364652 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2259,6 +2259,9 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event,
         int run_pending = 0;
         int err;
 
+        if (dev->nd_net != &init_net)
+                return NOTIFY_DONE;
+
         switch(event) {
         case NETDEV_REGISTER:
                 if (!idev && dev->mtu >= IPV6_MIN_MTU) {
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 5b596659177..d2d44dc22f1 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1525,6 +1525,9 @@ static int ndisc_netdev_event(struct notifier_block *this, unsigned long event,
 {
         struct net_device *dev = ptr;
 
+        if (dev->nd_net != &init_net)
+                return NOTIFY_DONE;
+
         switch (event) {
         case NETDEV_CHANGEADDR:
                 neigh_changeaddr(&nd_tbl, dev);
diff --git a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c
index dfc58fbdb68..64536a3ef2f 100644
--- a/net/ipv6/netfilter/ip6_queue.c
+++ b/net/ipv6/netfilter/ip6_queue.c
@@ -547,6 +547,9 @@ ipq_rcv_dev_event(struct notifier_block *this,
 {
         struct net_device *dev = ptr;
 
+        if (dev->nd_net != &init_net)
+                return NOTIFY_DONE;
+
         /* Drop any packets associated with the downed device */
         if (event == NETDEV_DOWN)
                 ipq_dev_drop(dev->ifindex);