[NET]: Make the loopback device per network namespace.

This patch makes loopback_dev per network namespace.  Adding
code to create a different loopback device for each network
namespace and adding the code to free a loopback device
when a network namespace exits.

This patch modifies all users the loopback_dev so they
access it as init_net.loopback_dev, keeping all of the
code compiling and working.  A later pass will be needed to
update the users to use something other than the initial network
namespace.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 2 deletions

diff --git a/net/core/dst.c b/net/core/dst.c
index ad5ffa19d809..16958e64e577 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -18,6 +18,7 @@
 #include <linux/types.h>
 #include <net/net_namespace.h>
 
+#include <net/net_namespace.h>
 #include <net/dst.h>
 
 /*
@@ -278,11 +279,11 @@ static inline void dst_ifdown(struct dst_entry *dst, struct net_device *dev,
         if (!unregister) {
                 dst->input = dst->output = dst_discard;
         } else {
-                dst->dev = loopback_dev;
+                dst->dev = init_net.loopback_dev;
                 dev_hold(dst->dev);
                 dev_put(dev);
                 if (dst->neighbour && dst->neighbour->dev == dev) {
-                        dst->neighbour->dev = loopback_dev;
+                        dst->neighbour->dev = init_net.loopback_dev;
                         dev_put(dev);
                         dev_hold(dst->neighbour->dev);
                 }