From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762609AbbA1FUR (ORCPT ); Wed, 28 Jan 2015 00:20:17 -0500 Received: from mail.kernel.org ([198.145.29.136]:37655 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933763AbbA1EQO (ORCPT ); Tue, 27 Jan 2015 23:16:14 -0500 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Xiubo Li , Mark Brown , Zefan Li Subject: [PATCH 3.4 031/177] regmap: debugfs: fix possbile NULL pointer dereference Date: Wed, 28 Jan 2015 12:07:09 +0800 Message-Id: <1422418236-12852-62-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1422418050-12581-1-git-send-email-lizf@kernel.org> References: <1422418050-12581-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiubo Li 3.4.106-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit 2c98e0c1cc6b8e86f1978286c3d4e0769ee9d733 upstream. If 'map->dev' is NULL and there will lead dev_name() to be NULL pointer dereference. So before dev_name(), we need to have check of the map->dev pionter. We also should make sure that the 'name' pointer shouldn't be NULL for debugfs_create_dir(). So here using one default "dummy" debugfs name when the 'name' pointer and 'map->dev' are both NULL. Signed-off-by: Xiubo Li Signed-off-by: Mark Brown [lizf: Backported to 3.4: dev_name() is passed to debugfs_create_dir() in 3.4] Signed-off-by: Zefan Li --- drivers/base/regmap/regmap-debugfs.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index 8ab1eab..1db1289 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -244,7 +244,12 @@ static const struct file_operations regmap_access_fops = { void regmap_debugfs_init(struct regmap *map) { - map->debugfs = debugfs_create_dir(dev_name(map->dev), + const char *devname = "dummy"; + + if (map->dev) + devname = dev_name(map->dev); + + map->debugfs = debugfs_create_dir(devname, regmap_debugfs_root); if (!map->debugfs) { dev_warn(map->dev, "Failed to create debugfs directory\n"); -- 1.9.1