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=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 5B003C433E0 for ; Tue, 30 Jun 2020 10:47:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 202CC2065F for ; Tue, 30 Jun 2020 10:47:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=web.de header.i=@web.de header.b="qfVS7SLN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732619AbgF3KrW (ORCPT ); Tue, 30 Jun 2020 06:47:22 -0400 Received: from mout.web.de ([212.227.15.3]:36763 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732510AbgF3KrU (ORCPT ); Tue, 30 Jun 2020 06:47:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1593514025; bh=bW0dU0D65jfP7kb5Hr9vfPa9nw3+9XUubQ8AWpz+DnA=; h=X-UI-Sender-Class:Subject:To:Cc:References:From:Date:In-Reply-To; b=qfVS7SLNwC/ErM638VtVhsKOnvmBPGWa7AYhZSgbZJFhDVU6RUB0YWvh6GyJUoCTA 596cUESPNCzZtRZN4qoV3dvBiVEwrfAtrXlatg0UoSbvB9K5V/xWrJU/343NpugHz5 K0gKGknLYficofLUde2ulJVoydeZadhEQsuIH8aA= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from [192.168.1.2] ([2.243.105.212]) by smtp.web.de (mrweb005 [213.165.67.108]) with ESMTPSA (Nemesis) id 1Mrfou-1j55GX2eo8-00neTl; Tue, 30 Jun 2020 12:47:05 +0200 Subject: Re: [PATCH v2] usb: mtu3: Fix NULL pointer dereferences To: Chunfeng Yun , Greg Kroah-Hartman , Matthias Brugger , linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Colin Ian King References: <1593502942-24455-1-git-send-email-chunfeng.yun@mediatek.com> From: Markus Elfring Autocrypt: addr=Markus.Elfring@web.de; 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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <1593502942-24455-1-git-send-email-chunfeng.yun@mediatek.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:/rGr2Nx4vkPR57gCHYowrZOB8KWU+aTDjhBY6NYTxgX3lg6M6rf k3omu3Jszm19XWe4Tj558zLVMPfOZs4MaKn9V10eBpFM3ODC1tvKRDUmgjmwpEB+lQxmGFw iGqAWmKnOZMPjEY41s1HYcCT3T3Z4ooNAWAejF1zBxttVd2ktlDhDUjUDIBTTVFcFW/iDkH vioNBP6OcmbMtyLLKZh7Q== X-UI-Out-Filterresults: notjunk:1;V03:K0:CQjErKL30T8=:jAQgQ5tHJAD+GSPqjruEma u99s4AhkkCL3I0MYUx/fDZ4kuOkzoSpZ1/zAAviTGLxAUhsXn2vkRjoRINNFcflBc4L8p2euH oExPWU3PoMTiPtV4xNM8IFS9vLVY4oZqMBHlKQcGuStf/9UHZRUJ33qvqcQPaVZel2EXwtol6 bC6E6Iw79UYjJsugaR40i95NSYOkfg8fR0SapLZwi2StQoSkKDeysoqI9VhGl0uCqg2rd9Ppf qK+bHOprwHu8zpiJrP2Hn9qdPF1J7fHyY7Fe4YplxA3iAbkttg+eJjHetMz+KrM6SoOs+m93K a53/FqxziQtS85GvSq1apC9GAK9HAmD4ZKVd+OQI5X32qKUdJnxie1avd38dKIWciTvtiaFDn LB9owCbiGsbbbnFgpFjOvxbVBlQl6UIRa2Dc/L0KVOKakG4wXgFoBiczU1s+0VsV5xF2ecolU 93/XolrTRQlskm4DuC8Yo+xbNwNo2pFthrEMqSGvYN9b73xXxSvFpHW0cB4DxndyXrT5oXNsH e7M4kwHufd8ufUqKdjEvbn87klUt32CnaR1YCBfVDrVnUZTiFU4EbR/eQA6NSuC70/eOo0ah1 SEIp81tPgiErpazD/so0ZeNUoEJYPZ5sCzG7+MgDmbdGJBolyvNlB+lkzSPdrsWffcey/oFoC 9lP+JHZSqo4gwx4/EcRDZMS5tlqgzk0Twr+WgPzmQyUUUbDYlqTcrGZy0SBTEM6eVDAICsrs7 8dY1pJKI6S8CFT8ku6z9tbcj4EYUIx6KVnkWzEcPWWPt2bDYE6/ZvwVM0c3/1jct0NWuSPRPI MA0jD47C2yKcviFPXjBpgD4SnMtt7ErUCXeJEWCXMnFKDhIT0wjnKkXWRo9oTfhARQzuRon7z bDi7G4zXrSoJ0DvKsNZWq95BT5VT5Fsqwfrj2kUZloTbJNHH1p4nQFgNFjUAQ3PWysA5+HAQ1 UXOuGTNWP00B9gzmt7f1reBAdLXxDIiKG6wrHzUUvHdKWz0O/ytj76Su7GchG3vJ+Ku1BTKL/ UsaEUYcBljVo9ikGkMjKTdEmMaXy9dOr91zJQrKOuMm+JHgyE5js7Zr4oJp0r+5HXp96/V5xN uvc6buOwhodzdsAILUDgWPASFJ3X6aNBSvbuxGoaxJblk04indRtEHmLwLK1V5mclaGISJ1ft IFHlkoZzS8mDcebl6XGNTbGNt6TTyO5S7GtCAjK5IGR/CIJi+cQ4sCXUQR8B2OljbtEyzHiQJ g0V69yEXyyThKkEmR Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org > Some pointers are dereferenced before successful checks. I propose to reconsider and improve also this change description. * Would a null pointer dereference be possible only with the variables =E2= =80=9Cmep=E2=80=9D and =E2=80=9Cmreq=E2=80=9D in the implementation of the function =E2=80= =9Cmtu3_gadget_dequeue=E2=80=9D? (Can it make sense to split the patch according to this detail?) * How do you think about to convert any more variable initialisations to later assignments? * Will it become helpful to add the tag =E2=80=9CFixes=E2=80=9D to the com= mit message? =E2=80=A6 > --- > v2: nothing changed, but abandon another patch Are there chances to take any previous patch review comments better into a= ccount (besides the shown reduction of update steps)? > --- > drivers/usb/mtu3/mtu3_gadget.c | 25 ++++++++++++++++++------- I suggest to replace the triple dashes before this diffstat by a blank lin= e. Regards, Markus