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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 89C45C10F14 for ; Thu, 3 Oct 2019 15:58:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4860320830 for ; Thu, 3 Oct 2019 15:58:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570118333; bh=qOgqvqjCkUD8COe5UC9OHjXjf/iIdtSx/nJitqT3eqk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jlPMjoTErguKi2XjnpLzHIRqcd0jnV0iEVD3adRXT6bVqFipry/8ImQMMH7x4FjK1 cUw7ojAxq8jpZJgvx9P5hnVgajlavAP24ioTACIXm6JPqGy8qqQ7zgDmieB85FpVac MUyfyjHnGqamxB5UaEeA1sOEdnGUXfLHPYRfSEaw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730070AbfJCP6w (ORCPT ); Thu, 3 Oct 2019 11:58:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:41662 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729062AbfJCP6s (ORCPT ); Thu, 3 Oct 2019 11:58:48 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7DC2A20700; Thu, 3 Oct 2019 15:58:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570118327; bh=qOgqvqjCkUD8COe5UC9OHjXjf/iIdtSx/nJitqT3eqk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kQueA1yz2fHGAm8NyGVp4K/tJmWvdnpNKHrBk/DzdrSMGQLjSJeHlyOc9xLpeKCt0 Ip/Y+34YwKxpW6gvknaPCMCHZb355qWOE0TrbmkB1yZkH9BLMmxyQ8lvmQtiSX2H5E HV+XBgHxSEaCUcuVDsQIm6T3iqMNVuOxyuZVl7Jk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jia-Ju Bai , Takashi Iwai , Sasha Levin Subject: [PATCH 4.4 44/99] ALSA: i2c: ak4xxx-adda: Fix a possible null pointer dereference in build_adc_controls() Date: Thu, 3 Oct 2019 17:53:07 +0200 Message-Id: <20191003154316.732713960@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191003154252.297991283@linuxfoundation.org> References: <20191003154252.297991283@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jia-Ju Bai [ Upstream commit 2127c01b7f63b06a21559f56a8c81a3c6535bd1a ] 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 Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/i2c/other/ak4xxx-adda.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/sound/i2c/other/ak4xxx-adda.c b/sound/i2c/other/ak4xxx-adda.c index bf377dc192aa7..d33e02c317129 100644 --- a/sound/i2c/other/ak4xxx-adda.c +++ b/sound/i2c/other/ak4xxx-adda.c @@ -789,11 +789,12 @@ static int build_adc_controls(struct snd_akm4xxx *ak) return err; memset(&knew, 0, sizeof(knew)); - knew.name = ak->adc_info[mixer_ch].selector_name; - if (!knew.name) { + if (!ak->adc_info || + !ak->adc_info[mixer_ch].selector_name) { knew.name = "Capture Channel"; knew.index = mixer_ch + ak->idx_offset * 2; - } + } else + knew.name = ak->adc_info[mixer_ch].selector_name; knew.iface = SNDRV_CTL_ELEM_IFACE_MIXER; knew.info = ak4xxx_capture_source_info; -- 2.20.1