[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, 3 insertions, 2 deletions

diff --git a/drivers/net/pppol2tp.c b/drivers/net/pppol2tp.c
index abe91cb595f4..2eb424ba58e5 100644
--- a/drivers/net/pppol2tp.c
+++ b/drivers/net/pppol2tp.c
@@ -91,6 +91,7 @@
 #include <linux/hash.h>
 #include <linux/sort.h>
 #include <linux/proc_fs.h>
+#include <net/net_namespace.h>
 #include <net/dst.h>
 #include <net/ip.h>
 #include <net/udp.h>
@@ -2444,7 +2445,7 @@ static int __init pppol2tp_init(void)
                 goto out_unregister_pppol2tp_proto;
 
 #ifdef CONFIG_PROC_FS
-        pppol2tp_proc = create_proc_entry("pppol2tp", 0, proc_net);
+        pppol2tp_proc = create_proc_entry("pppol2tp", 0, init_net.proc_net);
         if (!pppol2tp_proc) {
                 err = -ENOMEM;
                 goto out_unregister_pppox_proto;
@@ -2469,7 +2470,7 @@ static void __exit pppol2tp_exit(void)
         unregister_pppox_proto(PX_PROTO_OL2TP);
 
 #ifdef CONFIG_PROC_FS
-        remove_proc_entry("pppol2tp", proc_net);
+        remove_proc_entry("pppol2tp", init_net.proc_net);
 #endif
         proto_unregister(&pppol2tp_sk_proto);
 }