[PATCH 13/23] user: Add user namespaces into ns_idr

[Kirill Tkhai <ktkhai@virtuozzo.com>]

Now they are exposed in /proc/namespace/ directory.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
---
 kernel/user_namespace.c |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 367a942bb484..bbfd7f0f9e7c 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -137,7 +137,13 @@ int create_user_ns(struct cred *new)
 		goto fail_keyring;
 
 	set_cred_user_ns(new, ns);
+
+	if (ns_idr_register(&ns->ns))
+		goto fail_sysctl;
+
 	return 0;
+fail_sysctl:
+	retire_userns_sysctls(ns);
 fail_keyring:
 #ifdef CONFIG_PERSISTENT_KEYRINGS
 	key_put(ns->persistent_keyring_register);
@@ -186,6 +192,7 @@ static void free_user_ns(struct work_struct *work)
 	do {
 		struct ucounts *ucounts = ns->ucounts;
 		parent = ns->parent;
+		ns_idr_unregister(&ns->ns);
 		if (ns->gid_map.nr_extents > UID_GID_MAP_MAX_BASE_EXTENTS) {
 			kfree(ns->gid_map.forward);
 			kfree(ns->gid_map.reverse);
@@ -1327,6 +1334,7 @@ const struct proc_ns_operations userns_operations = {
 static __init int user_namespaces_init(void)
 {
 	user_ns_cachep = KMEM_CACHE(user_namespace, SLAB_PANIC);
-	return 0;
+
+	return ns_idr_register(&init_user_ns.ns);
 }
 subsys_initcall(user_namespaces_init);