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=-10.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 091EAC433E1 for ; Thu, 6 Aug 2020 18:35:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57FA2221E3 for ; Thu, 6 Aug 2020 18:35:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729228AbgHFSfL (ORCPT ); Thu, 6 Aug 2020 14:35:11 -0400 Received: from relay10.mail.gandi.net ([217.70.178.230]:59905 "EHLO relay10.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728674AbgHFSej (ORCPT ); Thu, 6 Aug 2020 14:34:39 -0400 Received: from [192.168.1.4] (unknown [176.88.145.153]) (Authenticated sender: cengiz@kernel.wtf) by relay10.mail.gandi.net (Postfix) with ESMTPSA id A4228240008; Thu, 6 Aug 2020 18:34:25 +0000 (UTC) From: Cengiz Can To: CC: , , , , , , , Cengiz Can Date: Thu, 06 Aug 2020 21:34:22 +0300 Message-ID: <173c50d7bb0.2bfa.85c738e3968116fc5c0dc2de74002084@kernel.wtf> In-Reply-To: <20200801220101.2783-1-cengiz@kernel.wtf> References: <20200731083856.GF3703480@smile.fi.intel.com> <20200801220101.2783-1-cengiz@kernel.wtf> User-Agent: AquaMail/1.25.2-1672 (build: 102500008) Subject: Re: [PATCH v6] staging: atomisp: move null check to earlier point MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="us-ascii" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Andy, Can I get some feedback on v6 please? I hope it suits your standards this time. Thank you On August 2, 2020 01:02:22 Cengiz Can wrote: > `find_gmin_subdev()` that returns a pointer to `struct > gmin_subdev` can return NULL. > > In `gmin_v2p8_ctrl()` there's a call to this function but the > possibility of a NULL was not checked before its being dereferenced, > i.e.: > > /* Acquired here --------v */ > struct gmin_subdev *gs = find_gmin_subdev(subdev); > > /* v------Dereferenced here */ > if (gs->v2p8_gpio >= 0) { > ... > } > > With this change we're null checking `find_gmin_subdev()` result > and we return an error if that's the case. We also WARN() > for the sake of debugging. > > Signed-off-by: Cengiz Can > Reported-by: Coverity Static Analyzer CID 1465536 > Suggested-by: Mauro Carvalho Chehab > --- > > Please do note that this change introduces a new return value to > `gmin_v2p8_ctrl()`. > > [NEW] - raise a WARN and return -ENODEV if there are no subdevices. > - return result of `gpio_request` or `gpio_direction_output`. > - return 0 if GPIO is ON. > - return results of `regulator_enable` or `regulator_disable`. > - according to PMIC type, return result of `axp_regulator_set` > or `gmin_i2c_write`. > - return -EINVAL if unknown PMIC type. > > Patch Changelog: > v4: Fix minor typo in commit message > v5: Remove typo from email subject > v6: Remove duplicate Signed-off-by tag > > drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c > b/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c > index 0df46a1af5f0..1ad0246764a6 100644 > --- a/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c > +++ b/drivers/staging/media/atomisp/pci/atomisp_gmin_platform.c > @@ -871,6 +871,9 @@ static int gmin_v2p8_ctrl(struct v4l2_subdev *subdev, > int on) > int ret; > int value; > > + if (WARN_ON(!gs)) > + return -ENODEV; > + > if (gs->v2p8_gpio >= 0) { > pr_info("atomisp_gmin_platform: 2.8v power on GPIO %d\n", > gs->v2p8_gpio); > @@ -881,7 +884,7 @@ static int gmin_v2p8_ctrl(struct v4l2_subdev *subdev, > int on) > pr_err("V2P8 GPIO initialization failed\n"); > } > > - if (!gs || gs->v2p8_on == on) > + if (gs->v2p8_on == on) > return 0; > gs->v2p8_on = on; > > -- > 2.27.0