From patchwork Sat Dec 1 10:01:10 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Mc Guire X-Patchwork-Id: 1006330 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-i2c-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=osadl.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 436Rhf38v4z9s9G for ; Sat, 1 Dec 2018 21:05:21 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726394AbeLAVR3 (ORCPT ); Sat, 1 Dec 2018 16:17:29 -0500 Received: from www.osadl.org ([62.245.132.105]:50802 "EHLO www.osadl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726342AbeLAVR3 (ORCPT ); Sat, 1 Dec 2018 16:17:29 -0500 Received: from debian01.hofrr.at (178.115.242.59.static.drei.at [178.115.242.59]) by www.osadl.org (8.13.8/8.13.8/OSADL-2007092901) with ESMTP id wB1A49Qa015563; Sat, 1 Dec 2018 11:04:09 +0100 From: Nicholas Mc Guire To: Wolfram Sang Cc: Peter Rosin , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Nicholas Mc Guire Subject: [PATCH] i2c: mux: demux-pinctrl: handle failure case of devm_kstrdup() Date: Sat, 1 Dec 2018 11:01:10 +0100 Message-Id: <1543658470-20887-1-git-send-email-hofrat@osadl.org> X-Mailer: git-send-email 2.1.4 X-Spam-Status: No, score=-1.9 required=6.0 tests=BAYES_00 autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on www.osadl.org Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org devm_kstrdup() may return NULL if internal allocation failed. Thus using name, value is unsafe without being checked. As i2c_demux_pinctrl_probe() can return -ENOMEM in other cases a dev_err() message is included to make the failure location clear. Signed-off-by: Nicholas Mc Guire Fixes: e35478eac030 ("i2c: mux: demux-pinctrl: run properly with multiple instances") --- Problem located with experimental coccinelle script Q: The use of devm_kstrdup() seems a bit odd while technically not wrong, personally I think devm_kasprintf() would be more suitable here. Patch was compile tested with: multi_v7_defconfig (implies I2C_DEMUX_PINCTRL=y) Patch is against 4.20-rc4 (localversion-next is next-20181130) drivers/i2c/muxes/i2c-demux-pinctrl.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/i2c/muxes/i2c-demux-pinctrl.c b/drivers/i2c/muxes/i2c-demux-pinctrl.c index 035032e..c466999 100644 --- a/drivers/i2c/muxes/i2c-demux-pinctrl.c +++ b/drivers/i2c/muxes/i2c-demux-pinctrl.c @@ -244,6 +244,12 @@ static int i2c_demux_pinctrl_probe(struct platform_device *pdev) props[i].name = devm_kstrdup(&pdev->dev, "status", GFP_KERNEL); props[i].value = devm_kstrdup(&pdev->dev, "ok", GFP_KERNEL); + if (!props[i].name || !props[i].value) { + dev_err(&pdev->dev, + "chan %d name, value allocation failed\n", i); + err = -ENOMEM; + goto err_rollback; + } props[i].length = 3; of_changeset_init(&priv->chan[i].chgset);