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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D96D0C4332F for ; Thu, 9 Nov 2023 13:45:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234053AbjKINp5 (ORCPT ); Thu, 9 Nov 2023 08:45:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37030 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232167AbjKINpz (ORCPT ); Thu, 9 Nov 2023 08:45:55 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1B9A430CF for ; Thu, 9 Nov 2023 05:45:53 -0800 (PST) Received: from dggpemm500020.china.huawei.com (unknown [172.30.72.56]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4SR3BC5Qv8zfb1J; Thu, 9 Nov 2023 21:45:39 +0800 (CST) Received: from [10.174.176.88] (10.174.176.88) by dggpemm500020.china.huawei.com (7.185.36.49) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Thu, 9 Nov 2023 21:45:49 +0800 Message-ID: <89069fa4-7347-4364-8793-1ce705a00b92@huawei.com> Date: Thu, 9 Nov 2023 21:45:49 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH -next V2] erofs: code clean up for function erofs_read_inode() To: Gao Xiang , , CC: , , References: <20231109194821.1719430-1-wozizhi@huawei.com> <4d4202a7-6648-9d2c-3f0b-079a165c2ebf@linux.alibaba.com> From: Zizhi Wo In-Reply-To: <4d4202a7-6648-9d2c-3f0b-079a165c2ebf@linux.alibaba.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.176.88] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500020.china.huawei.com (7.185.36.49) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2023/11/9 21:14, Gao Xiang 写道: > Hi, > > On 2023/11/10 03:48, WoZ1zh1 wrote: >> Because variables "die" and "copied" only appear in case >> EROFS_INODE_LAYOUT_EXTENDED, move them from the outer space into this >> case. Also, call "kfree(copied)" earlier to avoid double free in the >> "error_out" branch. Some cleanups, no logic changes. >> >> Signed-off-by: WoZ1zh1 > > Please help use your real name here... > >> --- >>   fs/erofs/inode.c | 6 +++--- >>   1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c >> index b8ad05b4509d..a388c93eec34 100644 >> --- a/fs/erofs/inode.c >> +++ b/fs/erofs/inode.c >> @@ -19,7 +19,6 @@ static void *erofs_read_inode(struct erofs_buf *buf, >>       erofs_blk_t blkaddr, nblks = 0; >>       void *kaddr; >>       struct erofs_inode_compact *dic; >> -    struct erofs_inode_extended *die, *copied = NULL; >>       unsigned int ifmt; >>       int err; >> @@ -53,6 +52,8 @@ static void *erofs_read_inode(struct erofs_buf *buf, >>       switch (erofs_inode_version(ifmt)) { >>       case EROFS_INODE_LAYOUT_EXTENDED: >> +        struct erofs_inode_extended *die, *copied = NULL; > > Thanks for the patch, but in my own opinion: > > 1) It doesn't simplify the code OK, I'm sorry for the noise(;´༎ຶД༎ຶ`) > > 2) We'd like to avoid defining variables like this (in the >    switch block), and I even don't think this patch can compile. I tested this patch with gcc-12.2.1 locally and it compiled successfully. I'm not sure if this patch will fail in other environment with different compiler... > 3) The logic itself is also broken... Sorry, but I just don't understand why the logic itself is broken, and can you please explain more? Thanks, Zizhi Wo > Thanks, > Gao Xiang > >> + >>           vi->inode_isize = sizeof(struct erofs_inode_extended); >>           /* check if the extended inode acrosses block boundary */ >>           if (*ofs + vi->inode_isize <= sb->s_blocksize) { >> @@ -98,6 +99,7 @@ static void *erofs_read_inode(struct erofs_buf *buf, >>               inode->i_rdev = 0; >>               break; >>           default: >> +            kfree(copied); >>               goto bogusimode; >>           } >>           i_uid_write(inode, le32_to_cpu(die->i_uid)); >> @@ -117,7 +119,6 @@ static void *erofs_read_inode(struct erofs_buf *buf, >>               /* fill chunked inode summary info */ >>               vi->chunkformat = le16_to_cpu(die->i_u.c.format); >>           kfree(copied); >> -        copied = NULL; >>           break; >>       case EROFS_INODE_LAYOUT_COMPACT: >>           vi->inode_isize = sizeof(struct erofs_inode_compact); >> @@ -197,7 +198,6 @@ static void *erofs_read_inode(struct erofs_buf *buf, >>       err = -EFSCORRUPTED; >>   err_out: >>       DBG_BUGON(1); >> -    kfree(copied); >>       erofs_put_metabuf(buf); >>       return ERR_PTR(err); >>   } >