[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/msg.c b/ipc/msg.c
index 5b213d9..600e06f 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -124,6 +124,7 @@
}
mutex_unlock(&msg_ids(ns).mutex);
+ ipc_fini_ids(ns->ids[IPC_MSG_IDS]);
kfree(ns->ids[IPC_MSG_IDS]);
ns->ids[IPC_MSG_IDS] = NULL;
}
diff --git a/ipc/sem.c b/ipc/sem.c
index 0dafcc4..21b3289 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -161,6 +161,7 @@
}
mutex_unlock(&sem_ids(ns).mutex);
+ ipc_fini_ids(ns->ids[IPC_SEM_IDS]);
kfree(ns->ids[IPC_SEM_IDS]);
ns->ids[IPC_SEM_IDS] = NULL;
}
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;
}
diff --git a/ipc/util.c b/ipc/util.c
index 42479e4..cd8bb14 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -301,7 +301,7 @@
*/
rcu_assign_pointer(ids->entries, new);
- ipc_rcu_putref(old);
+ __ipc_fini_ids(ids, old);
return newsize;
}
diff --git a/ipc/util.h b/ipc/util.h
index c8fd6b9..e3aa2c5 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -83,6 +83,18 @@
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);