From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E78D3C43381 for ; Fri, 22 Mar 2019 16:44:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BFDA921900 for ; Fri, 22 Mar 2019 16:44:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727942AbfCVQow (ORCPT ); Fri, 22 Mar 2019 12:44:52 -0400 Received: from foss.arm.com ([217.140.101.70]:49338 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726603AbfCVQov (ORCPT ); Fri, 22 Mar 2019 12:44:51 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5F85BA78; Fri, 22 Mar 2019 09:44:51 -0700 (PDT) Received: from [10.1.196.69] (e112269-lin.cambridge.arm.com [10.1.196.69]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7204A3F59C; Fri, 22 Mar 2019 09:44:50 -0700 (PDT) Subject: Re: [PATCH] firmware: arm_scmi: Fix to check return value of of_match_device To: Aditya Pakki Cc: kjlu@umn.edu, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sudeep Holla References: <20190318230430.8273-1-pakki001@umn.edu> From: Steven Price Message-ID: <6053ea18-f092-bb4a-fe0a-a40eda1abfdd@arm.com> Date: Fri, 22 Mar 2019 16:44:49 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: <20190318230430.8273-1-pakki001@umn.edu> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 18/03/2019 23:04, Aditya Pakki wrote: > of_match_device can return NULL if no matching device is found. This patch > checks and returns -ENODEV in such a scenario. > > Signed-off-by: Aditya Pakki > --- > drivers/firmware/arm_scmi/driver.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c > index 8f952f2f1a29..0e0330b44b7b 100644 > --- a/drivers/firmware/arm_scmi/driver.c > +++ b/drivers/firmware/arm_scmi/driver.c > @@ -799,6 +799,8 @@ static int scmi_probe(struct platform_device *pdev) > } > > desc = of_match_device(scmi_of_match, dev)->data; > + if (!desc) > + return -ENODEV; If of_match_device() returns NULL, we've already dereferenced it due to the "->data" access. This would be better changed to be a call to of_device_get_match_data() which handles the NULL return gracefully. Steve