[NETNS]: Process IP layer in the context of the correct namespace.

Replace all the rest of the init_net with a proper net on the IP layer.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index dc494ea..349fae5 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -351,7 +351,7 @@
 			 * itself out.
 			 */
 			security_sk_classify_flow(sk, &fl);
-			if (ip_route_output_flow(&init_net, &rt, &fl, sk, 0))
+			if (ip_route_output_flow(sk->sk_net, &rt, &fl, sk, 0))
 				goto no_route;
 		}
 		sk_setup_caps(sk, &rt->u.dst);