[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, 5 insertions, 0 deletions

diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index 328759c32d61..6644e8f5f199 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -122,6 +122,11 @@ int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
         unsigned short vlan_TCI;
         __be16 proto;
 
+        if (dev->nd_net != &init_net) {
+                kfree_skb(skb);
+                return -1;
+        }
+
         if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
                 return -1;