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=-2.3 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 BB8CAC73C66 for ; Sun, 14 Jul 2019 12:47:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E71D20820 for ; Sun, 14 Jul 2019 12:47:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=web.de header.i=@web.de header.b="X5Al4uIl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728423AbfGNMr5 (ORCPT ); Sun, 14 Jul 2019 08:47:57 -0400 Received: from mout.web.de ([212.227.17.12]:60511 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728351AbfGNMr4 (ORCPT ); Sun, 14 Jul 2019 08:47:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1563108442; bh=Bv58aXwasISoukBgAwwIyQdm3DHnY22HSUajDGxRpUE=; h=X-UI-Sender-Class:Cc:References:Subject:To:From:Date:In-Reply-To; b=X5Al4uIle2ec6UTEliCb2RHjk1L7MXUIa8nKA7OJApxzBthvWfdBl2tQ2ktVYZM63 ZYOw2tAW9qDolDVyH3qHYhVvqSbZhY3twptIOUIkyWVC4xEsIxNhQ7Kx7OS+N5hnwd pjKqmVwCVfpW5hBQAbj94loVCe1ejBalR+Uc14q8= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from [192.168.1.2] ([78.49.159.144]) by smtp.web.de (mrweb101 [213.165.67.124]) with ESMTPSA (Nemesis) id 0LpNwf-1iRDWG3tJt-00fEQC; Sun, 14 Jul 2019 14:47:22 +0200 Cc: kernel-janitors@vger.kernel.org, LKML , Cheng Shengyu , Jaroslav Kysela , Krzysztof Kozlowski , Liam Girdwood , Mark Brown , Sangbeom Kim , Sylwester Nawrocki , Takashi Iwai , Xue Zhihong , Yi Wang References: <1562989575-33785-3-git-send-email-wen.yang99@zte.com.cn> Subject: Re: [2/2] ASoC: samsung: odroid: fix a double-free issue for cpu_dai To: Wen Yang , alsa-devel@alsa-project.org From: Markus Elfring Openpgp: preference=signencrypt Autocrypt: addr=Markus.Elfring@web.de; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <1562989575-33785-3-git-send-email-wen.yang99@zte.com.cn> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB X-Provags-ID: V03:K1:ARMVCvM4n0fZixFkmnwA6Q1ueCcqChHYMLocwTvLTJOsT4zwMJv ZZnCMfu1tzzrYiauyKZXsAacRmYKQrienBCc8fSAk+ek+GEVJRon6ZzOKulL4F+hs5/WgWn IGpm/iS5E1T2oXDEeVpKgGYeuEcd7r4FWdca3cG44QQJthjHf3b8uOtYeddG6S3kNPE11BN a3GAoxdoqlR76h4N0fm6A== X-UI-Out-Filterresults: notjunk:1;V03:K0:X0JgI81HCiQ=:b1AbNe+rg82E6KQX5t8E79 5zSJdOfuTQlVmM8AmskRMNiGnlJpg51hawdwWrK5Mcb/+KqAuIMXd194W7On4vkzDWgxChWQ9 k63b9nSnQow/m/HqAVtwWDTnyTUWBrYyogk/8tNZMgNZ//NTBtAwVzrq2PUlQeUfPrTEPBzCQ ae6Y1ATsZWCC+JrhhAA+Ut8++VXTI3natF4PzcRzEKEyJ2SkmO1cagrhpR1EsloXg0x8xaJAM vn32F0GavgMGVEMmgCvGaMHvm4Hnjy0nzda7N46OdTKz6o9r1yvvh3H0fbpu8U/RIqjhpyFos MEM6M6rztpLUi4CoHoFeHOIssSRB6xcAsTPGBC2u78QjyJC6ZC6yQXLd+7LJWNuLsyk68NDtz dR8tF0wnbehTigWQPRwOEMbFWCEUDrZRd1AoCvg5kYH9Xy0zfoxklXChLSiYwHa923oNAIGvz +949uvZzuBDGMB9f6NjLR3BM1QnRSeb4hYx1kAQgoRMl97igVnXX0uAIcVv060aoWcGCLejZn TcrzN3W67SF5R2iw9ynfzopzE8oA9DhVjAZvAFb8tG+up6zpZUhKVMqWPgyoJ82bbIAJIGEWQ QxcRrSPo97ESH7ZhboGtPbjok1yhD8vKhFpecXw2ItkhcZhzMjzUgzo+XtKYzw7NVnGthBCcC 9+I9zgo1LpiAZbpQx6yNyXX7x8YFXzsaJBb47vZTv7puDZn05ZIxWB5PICWDHIpiS4kDfgaEv /Mvmf0/UDUVLB+xoZu6MxMPl4VR4BbxxFIPkwOH+BGwRkTNjOBDelvnzJ50p5BBmHdq53pYsQ P/el6xziXo8Ab6qUhPGC7iJXU7zBm2x64svx93///tIy3O+8flX9p3YkkQ60Y+sIenZLjOTXH ER3o/otiiyNxo8qmnb/HxEVeJU9DLHWhMEUm4sM9PRds+ocv0Ppvt0FGxe5lU9kVwfHPGjaXC ZAENQi/u0vNkEwS+ha1JHZwpVGOrdKoFJH8ih2+wjIv0QvV/E9TROHcfmvv0RZOn8uXby/6H5 RB6xCrHce52snfMCUmgXaILzPgNyVV1XV9WDtnGr6dZ4RrjhYD2op0XhehWLcYeztajYKxiOp BL5iaH3cFCQUndxf5CG71+G09lc4dBI3AaG Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > The cpu_dai variable is still being used after the of_node_put() call, Such an implementation detail is questionable. https://wiki.sei.cmu.edu/confluence/display/c/MEM30-C.+Do+not+access+freed+memory > which may result in double-free: This consequence is also undesirable. https://cwe.mitre.org/data/definitions/415.html Now I wonder if two update steps are really appropriate as a fix instead of using a single update step for the desired correction in this software module. Should a commit (including previous ones) usually be correct by itself? Regards, Markus