From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933110AbcHXMAk (ORCPT ); Wed, 24 Aug 2016 08:00:40 -0400 Received: from mail-wm0-f68.google.com ([74.125.82.68]:33235 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751268AbcHXMAi (ORCPT ); Wed, 24 Aug 2016 08:00:38 -0400 From: LABBE Corentin To: thierry.reding@gmail.com, maxime.ripard@free-electrons.com, wens@csie.org Cc: linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@googlegroups.com, linux-kernel@vger.kernel.org, LABBE Corentin Subject: [PATCH v3] pwm: sun4i: fix a possible NULL dereference Date: Wed, 24 Aug 2016 13:43:58 +0200 Message-Id: <1472039038-4047-1-git-send-email-clabbe.montjoie@gmail.com> X-Mailer: git-send-email 2.7.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org of_match_device could return NULL, and so cause a NULL pointer dereference later. For fixing this problem, we use of_device_get_match_data(), this will simplify the code a little by using a standard function for getting the match data. Testing the return value of of_device_get_match_data is also necessary for avoiding a second NULL deref on pwm->data. Reported-by: coverity (CID 1324139) Signed-off-by: LABBE Corentin --- Changes since v2: - Add a test on pwm->data for avoiding a second NULL deref. Changes since v1: - Use of_device_get_match_data() drivers/pwm/pwm-sun4i.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 03a99a5..fb76c55 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -309,9 +309,6 @@ static int sun4i_pwm_probe(struct platform_device *pdev) struct resource *res; u32 val; int i, ret; - const struct of_device_id *match; - - match = of_match_device(sun4i_pwm_dt_ids, &pdev->dev); pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL); if (!pwm) @@ -326,7 +323,9 @@ static int sun4i_pwm_probe(struct platform_device *pdev) if (IS_ERR(pwm->clk)) return PTR_ERR(pwm->clk); - pwm->data = match->data; + pwm->data = of_device_get_match_data(&pdev->dev); + if (!pwm->data) + return -EINVAL; pwm->chip.dev = &pdev->dev; pwm->chip.ops = &sun4i_pwm_ops; pwm->chip.base = -1; -- 2.7.3