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=-5.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 55868C7618B for ; Fri, 26 Jul 2019 10:33:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2A0E622BE8 for ; Fri, 26 Jul 2019 10:33:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=cirrus.com header.i=@cirrus.com header.b="SlRUOX1q" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726489AbfGZKdV (ORCPT ); Fri, 26 Jul 2019 06:33:21 -0400 Received: from mx0b-001ae601.pphosted.com ([67.231.152.168]:47188 "EHLO mx0b-001ae601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726074AbfGZKdU (ORCPT ); Fri, 26 Jul 2019 06:33:20 -0400 Received: from pps.filterd (m0077474.ppops.net [127.0.0.1]) by mx0b-001ae601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id x6QATkM6022536; Fri, 26 Jul 2019 05:33:09 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cirrus.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=PODMain02222019; bh=efZFnW5lzkbmhOQo8URSwv2VRRH5b1wiAs28rX/8rXI=; b=SlRUOX1qE8MOoZl5sN7q7+tN1MU5FJBFTOuHNCUM6Gy9I2Aijiwdl2VA913hBwdkKJos ZbHNXFzNaBZT0jBz97F1xYu0TOmlpnPz/vtB/mcv2v0+cLpcYOzE3HPvkjA1s7HdmcHK keNmALSMPJhDRlsnfO9PvprRQqeurtwzUXye0D7zypvSS9UxwuhsilDsvDd9D4LZbY/y cdmAAgGlFObSwGamngxIPo11pnFHywxj+NLO/+P71CzwAAmeZ2sdi9koUx4wYzgzuRqf K/wjd1NFijfJtcGPkN3GCwDzydA3DT4+kKwla0by8JdmizzKpf0y5Ko1s8tafBr1BTNM Gg== Authentication-Results: ppops.net; spf=fail smtp.mailfrom=ckeepax@opensource.cirrus.com Received: from ediex02.ad.cirrus.com ([87.246.76.36]) by mx0b-001ae601.pphosted.com with ESMTP id 2tx61nmr0v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Fri, 26 Jul 2019 05:33:09 -0500 Received: from EDIEX01.ad.cirrus.com (198.61.84.80) by EDIEX02.ad.cirrus.com (198.61.84.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1591.10; Fri, 26 Jul 2019 11:33:07 +0100 Received: from ediswmail.ad.cirrus.com (198.61.86.93) by EDIEX01.ad.cirrus.com (198.61.84.80) with Microsoft SMTP Server id 15.1.1591.10 via Frontend Transport; Fri, 26 Jul 2019 11:33:07 +0100 Received: from ediswmail.ad.cirrus.com (ediswmail.ad.cirrus.com [198.61.86.93]) by ediswmail.ad.cirrus.com (Postfix) with ESMTP id ADBD62DD; Fri, 26 Jul 2019 11:33:07 +0100 (BST) Date: Fri, 26 Jul 2019 11:33:07 +0100 From: Charles Keepax To: Jia-Ju Bai CC: , , , , , , , Subject: Re: [PATCH v3] input: touchscreen: wm97xx-core: Fix possible null-pointer dereferences in wm97xx_ts_input_open() Message-ID: <20190726103307.GC54126@ediswmail.ad.cirrus.com> References: <20190726102326.9266-1-baijiaju1990@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20190726102326.9266-1-baijiaju1990@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Proofpoint-SPF-Result: fail X-Proofpoint-SPF-Record: v=spf1 include:spf-001ae601.pphosted.com include:spf.protection.outlook.com -all X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 clxscore=1015 mlxscore=0 impostorscore=0 priorityscore=1501 adultscore=0 bulkscore=0 suspectscore=0 malwarescore=0 lowpriorityscore=0 mlxlogscore=733 spamscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1906280000 definitions=main-1907260135 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 26, 2019 at 06:23:26PM +0800, Jia-Ju Bai wrote: > In wm97xx_ts_input_open(), there is an if statement on line 507 to check > whether wm->mach_ops is NULL: > if (wm->mach_ops && wm->mach_ops->acc_enabled) > > When wm->mach_ops is NULL, it is used on line 521: > wm97xx_init_pen_irq(wm); > BUG_ON(!wm->mach_ops->irq_enable); > BUG_ON(!wm->mach_ops->irq_gpio); > wm97xx_reg_write(..., reg & ~(wm->mach_ops->irq_gpio)) > > Thus, possible null-pointer dereferences may occur. > > To fix these bugs, wm->mach_ops is checked at the beginning of > wm97xx_init_pen_irq(). > > These bugs found by a static analysis tool STCheck written by us. > > Signed-off-by: Jia-Ju Bai > --- > v2: > * Add a new check of wm->mach_ops in wm97xx_init_pen_irq(). > Thank Charles for helpful advice. > > v3: > * Print a message if wm->mach_ops is NULL in wm97xx_init_pen_irq(). > Thank Charles for helpful advice. > > --- Acked-by: Charles Keepax Thanks, Charles