[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/net/ipv4/udp.c b/net/ipv4/udp.c
index a581b543bff7..ef4d901ee9ad 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -98,6 +98,7 @@
 #include <linux/skbuff.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
+#include <net/net_namespace.h>
 #include <net/icmp.h>
 #include <net/route.h>
 #include <net/checksum.h>
@@ -1566,7 +1567,7 @@ int udp_proc_register(struct udp_seq_afinfo *afinfo)
         afinfo->seq_fops->llseek        = seq_lseek;
         afinfo->seq_fops->release       = seq_release_private;
 
-        p = proc_net_fops_create(afinfo->name, S_IRUGO, afinfo->seq_fops);
+        p = proc_net_fops_create(&init_net, afinfo->name, S_IRUGO, afinfo->seq_fops);
         if (p)
                 p->data = afinfo;
         else
@@ -1578,7 +1579,7 @@ void udp_proc_unregister(struct udp_seq_afinfo *afinfo)
 {
         if (!afinfo)
                 return;
-        proc_net_remove(afinfo->name);
+        proc_net_remove(&init_net, afinfo->name);
         memset(afinfo->seq_fops, 0, sizeof(*afinfo->seq_fops));
 }