From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751318AbbIGKeD (ORCPT ); Mon, 7 Sep 2015 06:34:03 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:39859 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750840AbbIGKd5 (ORCPT ); Mon, 7 Sep 2015 06:33:57 -0400 From: Luis Henriques To: Minchan Kim , Nitin Gupta Cc: Sergey Senozhatsky , linux-kernel@vger.kernel.org Subject: [PATCH] zram: fix possible use after free in zcomp_create() Date: Mon, 7 Sep 2015 11:33:53 +0100 Message-Id: <1441622033-8358-1-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org zcomp_create() verifies the success of zcomp_strm_{multi,siggle}_create() through comp->stream, which can potentially be pointing to memory that was freed if these functions returned an error. Fixes: beca3ec71fe5 ("zram: add multi stream functionality") Cc: stable@vger.kernel.org Signed-off-by: Luis Henriques --- drivers/block/zram/zcomp.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c index 965d1afb0eaa..f3db8158e172 100644 --- a/drivers/block/zram/zcomp.c +++ b/drivers/block/zram/zcomp.c @@ -212,6 +212,7 @@ static int zcomp_strm_multi_create(struct zcomp *comp, int max_strm) zstrm = zcomp_strm_alloc(comp); if (!zstrm) { kfree(zs); + comp->stream = NULL; return -ENOMEM; } list_add(&zstrm->list, &zs->idle_strm); @@ -262,6 +263,7 @@ static int zcomp_strm_single_create(struct zcomp *comp) zs->zstrm = zcomp_strm_alloc(comp); if (!zs->zstrm) { kfree(zs); + comp->stream = NULL; return -ENOMEM; } return 0;