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: 13463751 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E7FA13D97A; Tue, 21 Nov 2023 23:10:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none 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> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 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