[PATCH] Fix ipc entries removal

Fix two issuses related to ipc_ids->entries freeing.

1. When freeing ipc namespace we need to free entries allocated
   with ipc_init_ids().

2. When removing old entries in grow_ary() ipc_rcu_putref()
   may be called on entries set to &ids->nullentry earlier in
   ipc_init_ids().
   This is almost impossible without namespaces, but with
   them this situation becomes possible.

Found during OpenVZ testing after obvious leaks in beancounters.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Cc: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/ipc/shm.c b/ipc/shm.c
index bfbd317..d1198dd 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -116,6 +116,7 @@
 	}
 	mutex_unlock(&shm_ids(ns).mutex);
 
+	ipc_fini_ids(ns->ids[IPC_SHM_IDS]);
 	kfree(ns->ids[IPC_SHM_IDS]);
 	ns->ids[IPC_SHM_IDS] = NULL;
 }