[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, 6 insertions, 0 deletions

diff --git a/drivers/net/pppoe.c b/drivers/net/pppoe.c
index 53fcee26d6ae..60c0e4e17875 100644
--- a/drivers/net/pppoe.c
+++ b/drivers/net/pppoe.c
@@ -389,6 +389,9 @@ static int pppoe_rcv(struct sk_buff *skb,
         if (!(skb = skb_share_check(skb, GFP_ATOMIC)))
                 goto out;
 
+        if (dev->nd_net != &init_net)
+                goto drop;
+
         if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
                 goto drop;
 
@@ -418,6 +421,9 @@ static int pppoe_disc_rcv(struct sk_buff *skb,
         struct pppoe_hdr *ph;
         struct pppox_sock *po;
 
+        if (dev->nd_net != &init_net)
+                goto abort;
+
         if (!pskb_may_pull(skb, sizeof(struct pppoe_hdr)))
                 goto abort;