From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1424382Ab2LFQUY (ORCPT ); Thu, 6 Dec 2012 11:20:24 -0500 Received: from mail.tpi.com ([70.99.223.143]:4518 "EHLO mail.tpi.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1424087Ab2LFQUX (ORCPT ); Thu, 6 Dec 2012 11:20:23 -0500 From: Tim Gardner To: linux-kernel@vger.kernel.org Cc: Tim Gardner , David Airlie , Dave Airlie , "Paul E. McKenney" , Zhao Yakui , David Howells , dri-devel@lists.freedesktop.org Subject: [PATCH 3.7-rc8] ttm: Fix possible _manager memory allocation oops Date: Thu, 6 Dec 2012 09:20:06 -0700 Message-Id: <1354810806-81681-1-git-send-email-tim.gardner@canonical.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Memory for _manager is allocated using kzalloc() but the result is not checked. Free _manager on error lest memory become orphaned. I was led to scrutinize ttm_page_alloc_init() from a smatch warning: drivers/gpu/drm/ttm/ttm_page_alloc.c:799 ttm_page_alloc_init() error: potential null dereference '_manager'. (kzalloc returns null) Cc: David Airlie Cc: Dave Airlie Cc: "Paul E. McKenney" Cc: Zhao Yakui Cc: David Howells Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # 3.5+ Signed-off-by: Tim Gardner --- This patch applies to stable 3.5 and newer. drivers/gpu/drm/ttm/ttm_page_alloc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c index bd2a3b4..2c73d0a 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c @@ -798,6 +798,10 @@ int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages) pr_info("Initializing pool allocator\n"); _manager = kzalloc(sizeof(*_manager), GFP_KERNEL); + if (!_manager) { + pr_err("ttm: Could not allocate _manager.\n"); + return -ENOMEM; + } ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc"); @@ -817,6 +821,7 @@ int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages) &glob->kobj, "pool"); if (unlikely(ret != 0)) { kobject_put(&_manager->kobj); + kfree(_manager); _manager = NULL; return ret; } -- 1.7.9.5