From patchwork Mon Apr 26 18:41:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gabriel Krisman Bertazi X-Patchwork-Id: 12224849 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_GIT 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 EF967C433ED for ; Mon, 26 Apr 2021 18:42:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2539613C9 for ; Mon, 26 Apr 2021 18:42:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239355AbhDZSnV (ORCPT ); Mon, 26 Apr 2021 14:43:21 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:47414 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239301AbhDZSnK (ORCPT ); Mon, 26 Apr 2021 14:43:10 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id 8C38B1F41E27 From: Gabriel Krisman Bertazi To: amir73il@gmail.com, tytso@mit.edu, djwong@kernel.org Cc: david@fromorbit.com, jack@suse.com, dhowells@redhat.com, khazhy@google.com, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, Gabriel Krisman Bertazi , kernel@collabora.com Subject: [PATCH RFC 02/15] fanotify: Split fsid check from other fid mode checks Date: Mon, 26 Apr 2021 14:41:48 -0400 Message-Id: <20210426184201.4177978-3-krisman@collabora.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20210426184201.4177978-1-krisman@collabora.com> References: <20210426184201.4177978-1-krisman@collabora.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org FAN_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 creating a mark. Signed-off-by: Gabriel Krisman Bertazi --- fs/notify/fanotify/fanotify_user.c | 35 +++++++++++++++++++----------- 1 file changed, 22 insertions(+), 13 deletions(-) diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 0332c4afeec3..e0d113e3b65c 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -1055,7 +1055,23 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) } /* Check if filesystem can encode a unique fid */ -static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid) +static int fanotify_test_fid(struct path *path) +{ + /* + * 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 + * compare fid returned with event to the file handle of watched + * 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) + return -EOPNOTSUPP; + + return 0; +} + +static int fanotify_check_path_fsid(struct path *path, __kernel_fsid_t *fsid) { __kernel_fsid_t root_fsid; int err; @@ -1082,17 +1098,6 @@ static int fanotify_test_fid(struct path *path, __kernel_fsid_t *fsid) root_fsid.val[1] != fsid->val[1]) return -EXDEV; - /* - * 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 - * compare fid returned with event to the file handle of watched - * 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) - return -EOPNOTSUPP; - return 0; } @@ -1230,7 +1235,11 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask, } if (fid_mode) { - ret = fanotify_test_fid(&path, &__fsid); + ret = fanotify_check_path_fsid(&path, &__fsid); + if (ret) + goto path_put_and_out; + + ret = fanotify_test_fid(&path); if (ret) goto path_put_and_out;