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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DFC90C433FE for ; Mon, 25 Oct 2021 19:30:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BDCCF61184 for ; Mon, 25 Oct 2021 19:30:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235817AbhJYTdD (ORCPT ); Mon, 25 Oct 2021 15:33:03 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:58326 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235364AbhJYTbA (ORCPT ); Mon, 25 Oct 2021 15:31:00 -0400 Received: from localhost (unknown [IPv6:2804:14c:124:8a08::1002]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: krisman) by bhuna.collabora.co.uk (Postfix) with ESMTPSA id 26B8F1F433A7; Mon, 25 Oct 2021 20:28:35 +0100 (BST) From: Gabriel Krisman Bertazi To: amir73il@gmail.com, jack@suse.com Cc: djwong@kernel.org, tytso@mit.edu, david@fromorbit.com, dhowells@redhat.com, khazhy@google.com, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-ext4@vger.kernel.org, Gabriel Krisman Bertazi , kernel@collabora.com, Jan Kara Subject: [PATCH v9 06/31] fanotify: Split fsid check from other fid mode checks Date: Mon, 25 Oct 2021 16:27:21 -0300 Message-Id: <20211025192746.66445-7-krisman@collabora.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211025192746.66445-1-krisman@collabora.com> References: <20211025192746.66445-1-krisman@collabora.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org FAN_FS_ERROR will require fsid, but not necessarily require the filesystem to expose a file handle. Split those checks into different functions, so they can be used separately when setting up an event. While there, update a comment about tmpfs having 0 fsid, which is no longer true. Reviewed-by: Amir Goldstein Reviewed-by: Jan Kara Signed-off-by: Gabriel Krisman Bertazi --- Changes since v2: - FAN_ERROR -> FAN_FS_ERROR (Amir) - Update comment (Amir) Changes since v1: (Amir) - Sort hunks to simplify diff. Changes since RFC: (Amir) - Rename fanotify_check_path_fsid -> fanotify_test_fsid. - Use dentry directly instead of path. --- fs/notify/fanotify/fanotify_user.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 6895ec310b5d..adeae6d65e35 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -1300,16 +1300,15 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) return fd; } -/* Check if filesystem can encode a unique fid */ -static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid) +static int fanotify_test_fsid(struct dentry *dentry, __kernel_fsid_t *fsid) { __kernel_fsid_t root_fsid; int err; /* - * Make sure path is not in filesystem with zero fsid (e.g. tmpfs). + * Make sure dentry is not of a filesystem with zero fsid (e.g. fuse). */ - err = vfs_get_fsid(path->dentry, fsid); + err = vfs_get_fsid(dentry, fsid); if (err) return err; @@ -1317,10 +1316,10 @@ static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid) return -ENODEV; /* - * Make sure path is not inside a filesystem subvolume (e.g. btrfs) + * Make sure dentry is not of a filesystem subvolume (e.g. btrfs) * which uses a different fsid than sb root. */ - err = vfs_get_fsid(path->dentry->d_sb->s_root, &root_fsid); + err = vfs_get_fsid(dentry->d_sb->s_root, &root_fsid); if (err) return err; @@ -1328,6 +1327,12 @@ static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid) root_fsid.val[1] != fsid->val[1]) return -EXDEV; + return 0; +} + +/* Check if filesystem can encode a unique fid */ +static int fanotify_test_fid(struct dentry *dentry) +{ /* * We need to make sure that the file system supports at least * encoding a file handle so user can use name_to_handle_at() to @@ -1335,8 +1340,8 @@ static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid) * objects. However, name_to_handle_at() requires that the * filesystem also supports decoding file handles. */ - if (!path->dentry->d_sb->s_export_op || - !path->dentry->d_sb->s_export_op->fh_to_dentry) + if (!dentry->d_sb->s_export_op || + !dentry->d_sb->s_export_op->fh_to_dentry) return -EOPNOTSUPP; return 0; @@ -1487,7 +1492,11 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, } if (fid_mode) { - ret = fanotify_test_fid(&path, &__fsid); + ret = fanotify_test_fsid(path.dentry, &__fsid); + if (ret) + goto path_put_and_out; + + ret = fanotify_test_fid(path.dentry); if (ret) goto path_put_and_out; -- 2.33.0