[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, 4 insertions, 3 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 45b4c82148a0..cd2db728d183 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -62,6 +62,7 @@
 #include <linux/notifier.h>
 #include <linux/string.h>
 
+#include <net/net_namespace.h>
 #include <net/sock.h>
 #include <net/snmp.h>
 
@@ -2827,14 +2828,14 @@ static const struct file_operations if6_fops = {
 
 int __init if6_proc_init(void)
 {
-	if (!proc_net_fops_create("if_inet6", S_IRUGO, &if6_fops))
+	if (!proc_net_fops_create(&init_net, "if_inet6", S_IRUGO, &if6_fops))
 		return -ENOMEM;
 	return 0;
 }
 
 void if6_proc_exit(void)
 {
-	proc_net_remove("if_inet6");
+	proc_net_remove(&init_net, "if_inet6");
 }
 #endif	/* CONFIG_PROC_FS */
 
@@ -4293,6 +4294,6 @@ void __exit addrconf_cleanup(void)
 	rtnl_unlock();
 
 #ifdef CONFIG_PROC_FS
-	proc_net_remove("if_inet6");
+	proc_net_remove(&init_net, "if_inet6");
 #endif
 }