ipv6: Register some net/ipv6/ core sysctls at read-only root.

There are some sysctls left to be switched to read-only,
but they are all in ipv6, so complete with them.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 22 insertions, 7 deletions

diff --git a/net/ipv6/sysctl_net_ipv6.c b/net/ipv6/sysctl_net_ipv6.c
index 3804dcbbfab0..5c99274558bf 100644
--- a/net/ipv6/sysctl_net_ipv6.c
+++ b/net/ipv6/sysctl_net_ipv6.c
@@ -37,6 +37,10 @@ static ctl_table ipv6_table_template[] = {
                 .mode           = 0644,
                 .proc_handler   = &proc_dointvec
         },
+        { .ctl_name = 0 }
+};
+
+static ctl_table ipv6_table[] = {
         {
                 .ctl_name       = NET_IPV6_MLD_MAX_MSF,
                 .procname       = "mld_max_msf",
@@ -80,12 +84,6 @@ static int ipv6_sysctl_net_init(struct net *net)
 
         ipv6_table[2].data = &net->ipv6.sysctl.bindv6only;
 
-        /* We don't want this value to be per namespace, it should be global
-           to all namespaces, so make it read-only when we are not in the
-           init network namespace */
-        if (net != &init_net)
-                ipv6_table[3].mode = 0444;
-
         net->ipv6.sysctl.table = register_net_sysctl_table(net, net_ipv6_ctl_path,
                                                            ipv6_table);
         if (!net->ipv6.sysctl.table)
@@ -126,12 +124,29 @@ static struct pernet_operations ipv6_sysctl_net_ops = {
         .exit = ipv6_sysctl_net_exit,
 };
 
+static struct ctl_table_header *ip6_header;
+
 int ipv6_sysctl_register(void)
 {
-        return register_pernet_subsys(&ipv6_sysctl_net_ops);
+        int err = -ENOMEM;;
+
+        ip6_header = register_net_sysctl_rotable(net_ipv6_ctl_path, ipv6_table);
+        if (ip6_header == NULL)
+                goto out;
+
+        err = register_pernet_subsys(&ipv6_sysctl_net_ops);
+        if (err)
+                goto err_pernet;
+out:
+        return err;
+
+err_pernet:
+        unregister_net_sysctl_table(ip6_header);
+        goto out;
 }
 
 void ipv6_sysctl_unregister(void)
 {
+        unregister_net_sysctl_table(ip6_header);
         unregister_pernet_subsys(&ipv6_sysctl_net_ops);
 }