From: Serge E. Hallyn <serue@us.ibm.com>
Date: Wed, 16 Dec 2009 00:47:27 +0000 (-0800)
Subject: ipc ns: fix memory leak (idr)
X-Git-Tag: v2.6.27.45~3
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=f653e714dfd24c86d63e6f661a61cd167a2535e6;p=thirdparty%2Fkernel%2Fstable.git

ipc ns: fix memory leak (idr)

commit 7d6feeb287c61aafa88f06345387b1188edf4b86 upstream.

We have apparently had a memory leak since
7ca7e564e049d8b350ec9d958ff25eaa24226352 "ipc: store ipcs into IDRs" in
2007.  The idr of which 3 exist for each ipc namespace is never freed.

This patch simply frees them when the ipcns is freed.  I don't believe any
idr_remove() are done from rcu (and could therefore be delayed until after
this idr_destroy()), so the patch should be safe.  Some quick testing
showed no harm, and the memory leak fixed.

Caught by kmemleak.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/ipc/msg.c b/ipc/msg.c
index 2ceab7f12fcba..779f7622ebcb6 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -125,6 +125,7 @@ void msg_init_ns(struct ipc_namespace *ns)
 void msg_exit_ns(struct ipc_namespace *ns)
 {
 	free_ipcs(ns, &msg_ids(ns), freeque);
+	idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr);
 }
 #endif
 
diff --git a/ipc/sem.c b/ipc/sem.c
index 9eb9d31d6e5de..0c0b28ece0ccc 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -129,6 +129,7 @@ void sem_init_ns(struct ipc_namespace *ns)
 void sem_exit_ns(struct ipc_namespace *ns)
 {
 	free_ipcs(ns, &sem_ids(ns), freeary);
+	idr_destroy(&ns->ids[IPC_SEM_IDS].ipcs_idr);
 }
 #endif
 
diff --git a/ipc/shm.c b/ipc/shm.c
index 35a65be643317..37caa449e9ec3 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -100,6 +100,7 @@ static void do_shm_rmid(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp)
 void shm_exit_ns(struct ipc_namespace *ns)
 {
 	free_ipcs(ns, &shm_ids(ns), do_shm_rmid);
+	idr_destroy(&ns->ids[IPC_SHM_IDS].ipcs_idr);
 }
 #endif