[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>

1 files changed, 12 insertions, 0 deletions

diff --git a/ipc/util.h b/ipc/util.h
index c8fd6b9d77b5..e3aa2c5c97dc 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -83,6 +83,18 @@ void* ipc_rcu_alloc(int size);
 void ipc_rcu_getref(void *ptr);
 void ipc_rcu_putref(void *ptr);
 
+static inline void __ipc_fini_ids(struct ipc_ids *ids,
+                struct ipc_id_ary *entries)
+{
+        if (entries != &ids->nullentry)
+                ipc_rcu_putref(entries);
+}
+
+static inline void ipc_fini_ids(struct ipc_ids *ids)
+{
+        __ipc_fini_ids(ids, ids->entries);
+}
+
 struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id);
 struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id);
 void ipc_lock_by_ptr(struct kern_ipc_perm *ipcp);