From patchwork Tue Nov 21 23:10:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 168031 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:612c:2b07:b0:403:3b70:6f57 with SMTP id io7csp972677vqb; Tue, 21 Nov 2023 15:13:37 -0800 (PST) X-Google-Smtp-Source: AGHT+IHF2/+bHNZgz37WhXiM6QhxmOiSnBmzQLkazvVs4qQUQ8jS80wrdEylmaH3hf9D55m++ahq X-Received: by 2002:a17:90b:1e09:b0:280:cc16:f756 with SMTP id pg9-20020a17090b1e0900b00280cc16f756mr746529pjb.20.1700608417000; Tue, 21 Nov 2023 15:13:37 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700608416; cv=none; d=google.com; s=arc-20160816; b=wu8T16jMDPwEb5X9nclW1taQcwO2Qvd2DT7j2D3Kzi9sOmEHWfHVtj/O2DxjEvLoWl phSKxJkcxvJkYXzCuiEMju1QBeYLP3qLHpvDK7HoS7wdXsTr7YK/2ZutimfIaDhsg9di w1EgXrbKQWRWZ0JM1x8IKZBnhOL+TKxtuhAbMX5Ggr+YRTfeZ+EUrIC0LSAZ6WKHV7Bm DYvC5rLiEzfhxIJWaVf6VkKMHC8MkwznTUEZqz1TYSR6sfq6lpVCAMVHTvcJSQEc6rhv 3W+QIPyDuUMjJ2falmZbJxd5/+RnuB5i9ltzLR971554OAu7NjXWmSNZWWZrOk8G8KYf kldQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:references:subject:cc:to:from:date :user-agent:message-id; bh=Qdbn8oW9Psq0Up6EGJVQxVyzNgBHEcS3W5ajaiGnVAg=; fh=v5d2iK8lt4G1vkplZbghBt7rCstLvm5F4A2+SX42VNY=; b=gSyWcCP/WV9Oi+Np33ndqzCfT292kAzlWhsH1IKc5dDMpv/+47mjD+f8vkILKtgkc/ ZJCAA3KGLSXtZOKuqgTYaHYgToN7d5LLHP1F+kYq1aB0lj4djAagfp6e4/corZhWyx/I /joQH+w3m2miA9IU2dOP9qmql4VQ8it37Ozh45qdCqkcizKcQmDcYW8t+8Bs0DzbAoQr obJnVOXn2zSUwT0pCVG+u/UXUNWbdloLvhD9x1KECQy+c++k8WpsQYZIr/VxPPYsajls Lz+lPbeTUuQOLotYR9m1BJ0krnGpzLHgkUDRTJUiuuSAYi/ourgg2eJTdUCEyVU+s5ww ARWA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id x35-20020a17090a6c2600b0027cdee52324si141285pjj.74.2023.11.21.15.13.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Nov 2023 15:13:36 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 1A841806B54F; Tue, 21 Nov 2023 15:11:18 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234900AbjKUXLH (ORCPT + 99 others); Tue, 21 Nov 2023 18:11:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54964 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229695AbjKUXLA (ORCPT ); Tue, 21 Nov 2023 18:11:00 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 347C2191 for ; Tue, 21 Nov 2023 15:10:57 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D1B0C433CA; Tue, 21 Nov 2023 23:10:56 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.97-RC3) (envelope-from ) id 1r5Ztg-00000002dEb-3Uvn; Tue, 21 Nov 2023 18:11:12 -0500 Message-ID: <20231121231112.693841807@goodmis.org> User-Agent: quilt/0.67 Date: Tue, 21 Nov 2023 18:10:06 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Andrew Morton Subject: [PATCH 3/4] eventfs: Do not allow NULL parent to eventfs_start_creating() References: <20231121231003.516999942@goodmis.org> MIME-Version: 1.0 X-Spam-Status: No, score=-4.0 required=5.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Tue, 21 Nov 2023 15:11:18 -0800 (PST) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1783217171398519789 X-GMAIL-MSGID: 1783217171398519789 From: "Steven Rostedt (Google)" The eventfs directory is dynamically created via the meta data supplied by the existing trace events. All files and directories in eventfs has a parent. Do not allow NULL to be passed into eventfs_start_creating() as the parent because that should never happen. Warn if it does. Signed-off-by: Steven Rostedt (Google) --- fs/tracefs/inode.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c index 5b54948514fe..ae648deed019 100644 --- a/fs/tracefs/inode.c +++ b/fs/tracefs/inode.c @@ -509,20 +509,15 @@ struct dentry *eventfs_start_creating(const char *name, struct dentry *parent) struct dentry *dentry; int error; + /* Must always have a parent. */ + if (WARN_ON_ONCE(!parent)) + return ERR_PTR(-EINVAL); + error = simple_pin_fs(&trace_fs_type, &tracefs_mount, &tracefs_mount_count); if (error) return ERR_PTR(error); - /* - * If the parent is not specified, we create it in the root. - * We need the root dentry to do this, which is in the super - * block. A pointer to that is in the struct vfsmount that we - * have around. - */ - if (!parent) - parent = tracefs_mount->mnt_root; - if (unlikely(IS_DEADDIR(parent->d_inode))) dentry = ERR_PTR(-ENOENT); else