[NET]: Make /proc/net per network namespace

This patch makes /proc/net per network namespace.  It modifies the global
variables proc_net and proc_net_stat to be per network namespace.
The proc_net file helpers are modified to take a network namespace argument,
and all of their callers are fixed to pass &init_net for that argument.
This ensures that all of the /proc/net files are only visible and
usable in the initial network namespace until the code behind them
has been updated to be handle multiple network namespaces.

Making /proc/net per namespace is necessary as at least some files
in /proc/net depend upon the set of network devices which is per
network namespace, and even more files in /proc/net have contents
that are relevant to a single network namespace.

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

1 files changed, 5 insertions, 0 deletions

diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 6344b77f81a2..547247681345 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -8,6 +8,7 @@
 #include <linux/workqueue.h>
 #include <linux/list.h>
 
+struct proc_dir_entry;
 struct net {
         atomic_t                count;          /* To decided when the network
                                                  *  namespace should be freed.
@@ -17,6 +18,10 @@ struct net {
                                                  */
         struct list_head        list;           /* list of network namespaces */
         struct work_struct      work;           /* work struct for freeing */
+
+        struct proc_dir_entry   *proc_net;
+        struct proc_dir_entry   *proc_net_stat;
+        struct proc_dir_entry   *proc_net_root;
 };
 
 extern struct net init_net;