[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, 4 insertions, 0 deletions

diff --git a/net/bridge/br_stp_bpdu.c b/net/bridge/br_stp_bpdu.c
index 14f0c888eecc..0edbd2a1c3f3 100644
--- a/net/bridge/br_stp_bpdu.c
+++ b/net/bridge/br_stp_bpdu.c
@@ -17,6 +17,7 @@
 #include <linux/netfilter_bridge.h>
 #include <linux/etherdevice.h>
 #include <linux/llc.h>
+#include <net/net_namespace.h>
 #include <net/llc.h>
 #include <net/llc_pdu.h>
 #include <asm/unaligned.h>
@@ -141,6 +142,9 @@ int br_stp_rcv(struct sk_buff *skb, struct net_device *dev,
         struct net_bridge *br;
         const unsigned char *buf;
 
+        if (dev->nd_net != &init_net)
+                goto err;
+
         if (!p)
                 goto err;