[NET]: Make packet reception network namespace safe

This patch modifies every packet receive function
registered with dev_add_pack() to drop packets if they
are not from the initial network namespace.

This should ensure that the various network stacks do
not receive packets in a anything but the initial network
namespace until the code has been converted and is ready
for them.

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

1 files changed, 3 insertions, 0 deletions

diff --git a/net/x25/x25_dev.c b/net/x25/x25_dev.c
index 848a6b6f90a..f0679d28311 100644
--- a/net/x25/x25_dev.c
+++ b/net/x25/x25_dev.c
@@ -95,6 +95,9 @@ int x25_lapb_receive_frame(struct sk_buff *skb, struct net_device *dev,
         struct sk_buff *nskb;
         struct x25_neigh *nb;
 
+        if (dev->nd_net != &init_net)
+                goto drop;
+
         nskb = skb_copy(skb, GFP_ATOMIC);
         if (!nskb)
                 goto drop;