[NETNS]: Create ipv6 devconf-s for namespaces

This is the core. Declare and register the pernet subsys for
addrconf. The init callback the will create the devconf-s.

The init_net will reuse the existing statically declared confs,
so that accessing them from inside the ipv6 code will still
work.

The register_pernet_subsys() is moved above the ipv6_add_dev()
call for loopback, because this function will need the
net->devconf_dflt pointer to be already set.

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

2 files changed, 72 insertions, 12 deletions

diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h
index 10733a6f1bd4..06b4dc034bbd 100644
--- a/include/net/netns/ipv6.h
+++ b/include/net/netns/ipv6.h
@@ -28,5 +28,7 @@ struct netns_sysctl_ipv6 {
 
 struct netns_ipv6 {
         struct netns_sysctl_ipv6 sysctl;
+        struct ipv6_devconf     *devconf_all;
+        struct ipv6_devconf     *devconf_dflt;
 };
 #endif
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index bde50c686722..3ad081e9366b 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -4135,6 +4135,70 @@ static void addrconf_sysctl_unregister(struct inet6_dev *idev)
 
 #endif
 
+static int addrconf_init_net(struct net *net)
+{
+        int err;
+        struct ipv6_devconf *all, *dflt;
+
+        err = -ENOMEM;
+        all = &ipv6_devconf;
+        dflt = &ipv6_devconf_dflt;
+
+        if (net != &init_net) {
+                all = kmemdup(all, sizeof(ipv6_devconf), GFP_KERNEL);
+                if (all == NULL)
+                        goto err_alloc_all;
+
+                dflt = kmemdup(dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
+                if (dflt == NULL)
+                        goto err_alloc_dflt;
+        }
+
+        net->ipv6.devconf_all = all;
+        net->ipv6.devconf_dflt = dflt;
+
+#ifdef CONFIG_SYSCTL
+        err = __addrconf_sysctl_register(net, "all", NET_PROTO_CONF_ALL,
+                        NULL, all);
+        if (err < 0)
+                goto err_reg_all;
+
+        err = __addrconf_sysctl_register(net, "default", NET_PROTO_CONF_DEFAULT,
+                        NULL, dflt);
+        if (err < 0)
+                goto err_reg_dflt;
+#endif
+        return 0;
+
+#ifdef CONFIG_SYSCTL
+err_reg_dflt:
+        __addrconf_sysctl_unregister(all);
+err_reg_all:
+        kfree(dflt);
+#endif
+err_alloc_dflt:
+        kfree(all);
+err_alloc_all:
+        return err;
+}
+
+static void addrconf_exit_net(struct net *net)
+{
+#ifdef CONFIG_SYSCTL
+        __addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
+        __addrconf_sysctl_unregister(net->ipv6.devconf_all);
+#endif
+        if (net != &init_net) {
+                kfree(net->ipv6.devconf_dflt);
+                kfree(net->ipv6.devconf_all);
+        }
+}
+
+static struct pernet_operations addrconf_ops = {
+        .init = addrconf_init_net,
+        .exit = addrconf_exit_net,
+};
+
 /*
  *      Device notifier
  */
@@ -4167,6 +4231,8 @@ int __init addrconf_init(void)
                 return err;
         }
 
+        register_pernet_subsys(&addrconf_ops);
+
         /* The addrconf netdev notifier requires that loopback_dev
          * has it's ipv6 private information allocated and setup
          * before it can bring up and give link-local addresses
@@ -4190,7 +4256,7 @@ int __init addrconf_init(void)
                 err = -ENOMEM;
         rtnl_unlock();
         if (err)
-                return err;
+                goto errlo;
 
         ip6_null_entry.u.dst.dev = init_net.loopback_dev;
         ip6_null_entry.rt6i_idev = in6_dev_get(init_net.loopback_dev);
@@ -4218,16 +4284,11 @@ int __init addrconf_init(void)
 
         ipv6_addr_label_rtnl_register();
 
-#ifdef CONFIG_SYSCTL
-        __addrconf_sysctl_register(&init_net, "all", NET_PROTO_CONF_ALL,
-                        NULL, &ipv6_devconf);
-        __addrconf_sysctl_register(&init_net, "default", NET_PROTO_CONF_DEFAULT,
-                        NULL, &ipv6_devconf_dflt);
-#endif
-
         return 0;
 errout:
         unregister_netdevice_notifier(&ipv6_dev_notf);
+errlo:
+        unregister_pernet_subsys(&addrconf_ops);
 
         return err;
 }
@@ -4240,10 +4301,7 @@ void addrconf_cleanup(void)
 
         unregister_netdevice_notifier(&ipv6_dev_notf);
 
-#ifdef CONFIG_SYSCTL
-        __addrconf_sysctl_unregister(&ipv6_devconf_dflt);
-        __addrconf_sysctl_unregister(&ipv6_devconf);
-#endif
+        unregister_pernet_subsys(&addrconf_ops);
 
         rtnl_lock();