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=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 1230BC432C0 for ; Wed, 4 Dec 2019 03:14:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6A7F2073C for ; Wed, 4 Dec 2019 03:14:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726824AbfLDDOx (ORCPT ); Tue, 3 Dec 2019 22:14:53 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:48376 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726804AbfLDDOx (ORCPT ); Tue, 3 Dec 2019 22:14:53 -0500 Received: from DGGEMS412-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 885B553BE6C41356A36B; Wed, 4 Dec 2019 11:14:48 +0800 (CST) Received: from [10.134.22.195] (10.134.22.195) by smtp.huawei.com (10.3.19.212) with Microsoft SMTP Server (TLS) id 14.3.439.0; Wed, 4 Dec 2019 11:14:38 +0800 Subject: Re: [PATCH] erofs: zero out when listxattr is called with no xattr To: Gao Xiang , CC: LKML , David Michael , Miao Xie , Fang Wei , Wang Li , Gao Xiang , References: <20191201084040.29275-1-hsiangkao.ref@aol.com> <20191201084040.29275-1-hsiangkao@aol.com> From: Chao Yu Message-ID: <947ae429-d206-0859-ee5b-9bd37f7fd72b@huawei.com> Date: Wed, 4 Dec 2019 11:14:37 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20191201084040.29275-1-hsiangkao@aol.com> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.134.22.195] X-CFilter-Loop: Reflected Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 2019/12/1 16:40, Gao Xiang wrote: > From: Gao Xiang > > As David reported [1], ENODATA returns when attempting > to modify files by using EROFS as a overlayfs lower layer. > > The root cause is that listxattr could return unexpected > -ENODATA by mistake for inodes without xattr. That breaks > listxattr return value convention and it can cause copy > up failure when used with overlayfs. > > Resolve by zeroing out if no xattr is found for listxattr. > > [1] https://lore.kernel.org/r/CAEvUa7nxnby+rxK-KRMA46=exeOMApkDMAV08AjMkkPnTPV4CQ@mail.gmail.com > Fixes: cadf1ccf1b00 ("staging: erofs: add error handling for xattr submodule") > Cc: # 4.19+ > Signed-off-by: Gao Xiang Reviewed-by: Chao Yu Thanks,