[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, 10 insertions, 9 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 29cf00c5d865..618fb1c1dd47 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -92,6 +92,7 @@
 #include <linux/etherdevice.h>
 #include <linux/notifier.h>
 #include <linux/skbuff.h>
+#include <net/net_namespace.h>
 #include <net/sock.h>
 #include <linux/rtnetlink.h>
 #include <linux/proc_fs.h>
@@ -2556,24 +2557,24 @@ static int __init dev_proc_init(void)
 {
         int rc = -ENOMEM;
 
-        if (!proc_net_fops_create("dev", S_IRUGO, &dev_seq_fops))
+        if (!proc_net_fops_create(&init_net, "dev", S_IRUGO, &dev_seq_fops))
                 goto out;
-        if (!proc_net_fops_create("softnet_stat", S_IRUGO, &softnet_seq_fops))
+        if (!proc_net_fops_create(&init_net, "softnet_stat", S_IRUGO, &softnet_seq_fops))
                 goto out_dev;
-        if (!proc_net_fops_create("ptype", S_IRUGO, &ptype_seq_fops))
-                goto out_dev2;
+        if (!proc_net_fops_create(&init_net, "ptype", S_IRUGO, &ptype_seq_fops))
+                goto out_softnet;
 
         if (wext_proc_init())
-                goto out_softnet;
+                goto out_ptype;
         rc = 0;
 out:
         return rc;
+out_ptype:
+        proc_net_remove(&init_net, "ptype");
 out_softnet:
-        proc_net_remove("ptype");
-out_dev2:
-        proc_net_remove("softnet_stat");
+        proc_net_remove(&init_net, "softnet_stat");
 out_dev:
-        proc_net_remove("dev");
+        proc_net_remove(&init_net, "dev");
         goto out;
 }
 #else