[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>
diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index 78dd344..bde1297 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -932,6 +932,9 @@
{
struct arphdr *arp;
+ if (dev->nd_net != &init_net)
+ goto freeskb;
+
/* ARP header, plus 2 device addresses, plus 2 IP addresses. */
if (!pskb_may_pull(skb, (sizeof(struct arphdr) +
(2 * dev->addr_len) +
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 9706939..41d8964 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -382,6 +382,9 @@
struct iphdr *iph;
u32 len;
+ if (dev->nd_net != &init_net)
+ goto drop;
+
/* When the interface is in promisc. mode, drop all the crap
* that it receives, do not try to analyse it.
*/
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c
index 5ae4849..08ff623 100644
--- a/net/ipv4/ipconfig.c
+++ b/net/ipv4/ipconfig.c
@@ -426,6 +426,9 @@
unsigned char *sha, *tha; /* s for "source", t for "target" */
struct ic_device *d;
+ if (dev->nd_net != &init_net)
+ goto drop;
+
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
return NET_RX_DROP;
@@ -835,6 +838,9 @@
struct ic_device *d;
int len, ext_len;
+ if (dev->nd_net != &init_net)
+ goto drop;
+
/* Perform verifications before taking the lock. */
if (skb->pkt_type == PACKET_OTHERHOST)
goto drop;
