[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/decnet/dn_route.c b/net/decnet/dn_route.c
index 4cfea9563d2a..580e786d0c38 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -584,6 +584,9 @@ int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type
         struct dn_dev *dn = (struct dn_dev *)dev->dn_ptr;
         unsigned char padlen = 0;
 
+        if (dev->nd_net != &init_net)
+                goto dump_it;
+
         if (dn == NULL)
                 goto dump_it;