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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 DF464C7618B for ; Fri, 26 Jul 2019 12:26:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B396522ADA for ; Fri, 26 Jul 2019 12:26:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726944AbfGZM0d (ORCPT ); Fri, 26 Jul 2019 08:26:33 -0400 Received: from mx2.suse.de ([195.135.220.15]:55880 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726440AbfGZM0d (ORCPT ); Fri, 26 Jul 2019 08:26:33 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 6453BB64F; Fri, 26 Jul 2019 12:26:31 +0000 (UTC) Date: Fri, 26 Jul 2019 14:26:31 +0200 Message-ID: From: Takashi Iwai To: "Jia-Ju Bai" Cc: , , , , , Subject: Re: [PATCH v2] ALSA: i2c: ak4xxx-adda: Fix a possible null pointer dereference in build_adc_controls() In-Reply-To: <20190726021442.21177-1-baijiaju1990@gmail.com> References: <20190726021442.21177-1-baijiaju1990@gmail.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 26 Jul 2019 04:14:42 +0200, Jia-Ju Bai wrote: > > In build_adc_controls(), there is an if statement on line 773 to check > whether ak->adc_info is NULL: > if (! ak->adc_info || > ! ak->adc_info[mixer_ch].switch_name) > > When ak->adc_info is NULL, it is used on line 792: > knew.name = ak->adc_info[mixer_ch].selector_name; > > Thus, a possible null-pointer dereference may occur. > > To fix this bug, referring to lines 773 and 774, ak->adc_info > and ak->adc_info[mixer_ch].selector_name are checked before being used. > > This bug is found by a static analysis tool STCheck written by us. > > Signed-off-by: Jia-Ju Bai Applied, thanks. Takashi