From patchwork Tue Jul 26 09:31:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Yang Xu (Fujitsu)" X-Patchwork-Id: 12929019 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 58FF1C433EF for ; Tue, 26 Jul 2022 08:30:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237839AbiGZIat (ORCPT ); Tue, 26 Jul 2022 04:30:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237582AbiGZIaq (ORCPT ); Tue, 26 Jul 2022 04:30:46 -0400 Received: from mail1.bemta37.messagelabs.com (mail1.bemta37.messagelabs.com [85.158.142.113]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F2142B185 for ; Tue, 26 Jul 2022 01:30:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fujitsu.com; s=170520fj; t=1658824242; i=@fujitsu.com; bh=kZjL9mj8bftaXa8ATH95mWSrco3+0SztCl3e0KAjUgQ=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=TsQZhtIPRe08YGrNLoFtwZpX+hZbBA76jbG95Bn0sjXmBaNlBxCo7cHbWnw8QnQxV k6K8ShtfOEVAG229a0dQdmuRfy/PQXKmS0KxIHzOTHrHSaR2rhdks5/C1Uu2grxPou DOQbnwVnL1hF8NiqQ1VfKw7d32jpYIqgSHaBqtX47awChpeZMke/fsF76Q4tew2NbL r61ajuTqcR8HkCPzGRPv22VZn8o/fqJYjIhyxZ6pD8wksazeyKxJDrWMRhuO/VyYGZ iaBA8xj+09nEJEFBsgNh/gTXhR2a09T0a9QvE7k6Ti76Rbj+tWS5EhITpLtu8raKPP 15Ok8bnw0RaRA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrEIsWRWlGSWpSXmKPExsViZ8OxWddo2f0 kg+kdzBavD39itDjdspfdgclj06pONo/Pm+QCmKJYM/OS8isSWDP6Zh9jK/hwkrFi8U/xBsbv ixm7GLk4hAQ2Mkps3vCJvYuRE8hZwiQx6TULhL2HUeL0Hy0Qm01AU+JZ5wJmEFtEQFbi/4zVT CA2s4CtxLsf/9hAbGEge8PCmWA1LAKqEr3n94PV8Ap4SDz7c5wVxJYQUJCY8vA9WA2ngLXE2d PfoPZaSVx/840Zol5Q4uTMJywQ8yUkDr54wQzRqyhxqeMbI4RdIfH68CWouJrE1XObmCcwCs5 C0j4LSfsCRqZVjLZJRZnpGSW5iZk5uoYGBrqGhqYQ2tJcL7FKN1EvtVQ3L7+oJEPXUC+xvFgv tbhYr7gyNzknRS8vtWQTIzC4U4pTju5gPLbvl94hRkkOJiVR3qd995OE+JLyUyozEosz4otKc 1KLDzHKcHAoSfAeWAKUEyxKTU+tSMvMAUYaTFqCg0dJhPcoSJq3uCAxtzgzHSJ1ilGXY+rsf/ uZhVjy8vNSpcR59ZYCFQmAFGWU5sGNgEX9JUZZKWFeRgYGBiGegtSi3MwSVPlXjOIcjErCvNt BVvFk5pXAbXoFdAQT0BGftO+AHFGSiJCSamDitpBNexv2Iqfo5IPAg5w8IcxSC/MmVtl6vC+q UlysYPCkU2i6cs39IM51SU7PJsnurH0oqlcjNq+0QawqpU2m9EeRqaK+tPVuyQyNdQsytJ8dS ze2m6KR+N0v1vbOx4Bszv1XfNXzoyOsvye9fufCfM/wUq1n/sudGnu58sMvPjqoKvgk1EK0p2 Vj4SHurUcK3Zc9Yo0vFOKdwJ/BUhZYGX/h6WvHq9+eWFS0PpuoPzV8cde6DuaZyf6J7HGTeM0 8pojOZjK4tlFozz+Jq64fgkpuCZWfOi4gt8TJ9ug8SxX53GkT/4UKO33PPJMTwad7cbLoEybv tfmVunsnuLUZO646Vf2G4blHV1arEktxRqKhFnNRcSIA7DCTQXUDAAA= X-Env-Sender: xuyang2018.jy@fujitsu.com X-Msg-Ref: server-19.tower-732.messagelabs.com!1658824241!134515!1 X-Originating-IP: [62.60.8.179] X-SYMC-ESS-Client-Auth: outbound-route-from=pass X-StarScan-Received: X-StarScan-Version: 9.87.3; banners=-,-,- X-VirusChecked: Checked Received: (qmail 27694 invoked from network); 26 Jul 2022 08:30:41 -0000 Received: from unknown (HELO n03ukasimr04.n03.fujitsu.local) (62.60.8.179) by server-19.tower-732.messagelabs.com with ECDHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 26 Jul 2022 08:30:41 -0000 Received: from n03ukasimr04.n03.fujitsu.local (localhost [127.0.0.1]) by n03ukasimr04.n03.fujitsu.local (Postfix) with ESMTP id 66A86155; Tue, 26 Jul 2022 09:30:41 +0100 (BST) Received: from R01UKEXCASM126.r01.fujitsu.local (R01UKEXCASM126 [10.183.43.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by n03ukasimr04.n03.fujitsu.local (Postfix) with ESMTPS id 58706154; Tue, 26 Jul 2022 09:30:41 +0100 (BST) Received: from localhost.localdomain (10.167.220.84) by R01UKEXCASM126.r01.fujitsu.local (10.183.43.178) with Microsoft SMTP Server (TLS) id 15.0.1497.32; Tue, 26 Jul 2022 09:30:39 +0100 From: Yang Xu To: CC: , Yang Xu Subject: [PATCH v2 1/2] vfs: Add new setgid_create_umask test Date: Tue, 26 Jul 2022 17:31:20 +0800 Message-ID: <1658827881-2347-1-git-send-email-xuyang2018.jy@fujitsu.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <20220725142020.rtc2mgfhcw47v4t4@wittgenstein> References: <20220725142020.rtc2mgfhcw47v4t4@wittgenstein> MIME-Version: 1.0 X-Originating-IP: [10.167.220.84] X-ClientProxiedBy: G08CNEXCHPEKD08.g08.fujitsu.local (10.167.33.83) To R01UKEXCASM126.r01.fujitsu.local (10.183.43.178) X-Virus-Scanned: ClamAV using ClamSMTP Precedence: bulk List-ID: X-Mailing-List: fstests@vger.kernel.org The current_umask() is stripped from the mode directly in the vfs if the filesystem either doesn't support acls or the filesystem has been mounted without posic acl support. If the filesystem does support acls then current_umask() stripping is deferred to posix_acl_create(). So when the filesystem calls posix_acl_create() and there are no acls set or not supported then current_umask() will be stripped. This patch is also designed to test kernel patch behaviour "move S_ISGID stripping into the vfs* helper" Here we only use umask(S_IXGRP) to check S_ISGID stripping whether works correctly and S_IXGRP mode still exists. Also use noacl mount option to test another kernel bug fs: Add missing umask strip in vfs_tmpfile Signed-off-by: Yang Xu --- 1.add kernel commit id 2.use s_setgid_create_umask_idmapped_mounts instead of confused s_setgid_create_umask_idmapped src/vfs/idmapped-mounts.c | 429 ++++++++++++++++++++++++++++++++++++++ src/vfs/idmapped-mounts.h | 1 + src/vfs/utils.c | 14 ++ src/vfs/utils.h | 1 + src/vfs/vfstest.c | 205 +++++++++++++++++- tests/generic/998 | 46 ++++ tests/generic/998.out | 2 + 7 files changed, 697 insertions(+), 1 deletion(-) create mode 100755 tests/generic/998 create mode 100644 tests/generic/998.out diff --git a/src/vfs/idmapped-mounts.c b/src/vfs/idmapped-mounts.c index 63297d5f..f63ac44b 100644 --- a/src/vfs/idmapped-mounts.c +++ b/src/vfs/idmapped-mounts.c @@ -7664,6 +7664,425 @@ out: return fret; } +static int setgid_create_umask_idmapped(const struct vfstest_info *info) +{ + int fret = -1; + int file1_fd = -EBADF, open_tree_fd = -EBADF; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_IDMAP, + }; + pid_t pid; + int tmpfile_fd = -EBADF; + bool supported = false; + char path[PATH_MAX]; + mode_t mode; + + if (!caps_supported()) + return 0; + + if (fchmod(info->t_dir1_fd, S_IRUSR | + S_IWUSR | + S_IRGRP | + S_IWGRP | + S_IROTH | + S_IWOTH | + S_IXUSR | + S_IXGRP | + S_IXOTH | + S_ISGID), 0) { + log_stderr("failure: fchmod"); + goto out; + } + + /* Verify that the sid bits got raised. */ + if (!is_setgid(info->t_dir1_fd, "", AT_EMPTY_PATH)) { + log_stderr("failure: is_setgid"); + goto out; + } + + /* Changing mount properties on a detached mount. */ + attr.userns_fd = get_userns_fd(0, 10000, 10000); + if (attr.userns_fd < 0) { + log_stderr("failure: get_userns_fd"); + goto out; + } + + open_tree_fd = sys_open_tree(info->t_dir1_fd, "", + AT_EMPTY_PATH | + AT_NO_AUTOMOUNT | + AT_SYMLINK_NOFOLLOW | + OPEN_TREE_CLOEXEC | + OPEN_TREE_CLONE); + if (open_tree_fd < 0) { + log_stderr("failure: sys_open_tree"); + goto out; + } + + if (sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr))) { + log_stderr("failure: sys_mount_setattr"); + goto out; + } + + supported = openat_tmpfile_supported(open_tree_fd); + + /* Only umask with S_IXGRP because inode strip S_ISGID will check mode + * whether has group execute or search permission. + */ + umask(S_IXGRP); + mode = umask(S_IXGRP); + if (!(mode & S_IXGRP)) + die("failure: umask"); + + pid = fork(); + if (pid < 0) { + log_stderr("failure: fork"); + goto out; + } + if (pid == 0) { + if (!switch_ids(10000, 11000)) + die("failure: switch fsids"); + + /* create regular file via open() */ + file1_fd = openat(open_tree_fd, FILE1, O_CREAT | O_EXCL | O_CLOEXEC, S_IXGRP | S_ISGID); + if (file1_fd < 0) + die("failure: create"); + + /* Neither in_group_p() nor capable_wrt_inode_uidgid() so setgid + * bit needs to be stripped. + */ + if (is_setgid(open_tree_fd, FILE1, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(open_tree_fd, FILE1, 0)) + die("failure: is_ixgrp"); + + /* create directory */ + if (mkdirat(open_tree_fd, DIR1, 0000)) + die("failure: create"); + + if (xfs_irix_sgid_inherit_enabled(info->t_fstype)) { + /* We're not in_group_p(). */ + if (is_setgid(open_tree_fd, DIR1, 0)) + die("failure: is_setgid"); + } else { + /* Directories always inherit the setgid bit. */ + if (!is_setgid(open_tree_fd, DIR1, 0)) + die("failure: is_setgid"); + } + + if (is_ixgrp(open_tree_fd, DIR1, 0)) + die("failure: is_ixgrp"); + + /* create a special file via mknodat() vfs_create */ + if (mknodat(open_tree_fd, FILE2, S_IFREG | S_ISGID | S_IXGRP, 0)) + die("failure: mknodat"); + + if (is_setgid(open_tree_fd, FILE2, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(open_tree_fd, FILE2, 0)) + die("failure: is_ixgrp"); + + /* create a whiteout device via mknodat() vfs_mknod */ + if (mknodat(open_tree_fd, CHRDEV1, S_IFCHR | S_ISGID | S_IXGRP, 0)) + die("failure: mknodat"); + + if (is_setgid(open_tree_fd, CHRDEV1, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(open_tree_fd, CHRDEV1, 0)) + die("failure: is_ixgrp"); + + /* + * In setgid directories newly created files always inherit the + * gid from the parent directory. Verify that the file is owned + * by gid 10000, not by gid 11000. + */ + if (!expected_uid_gid(open_tree_fd, FILE1, 0, 10000, 10000)) + die("failure: check ownership"); + + /* + * In setgid directories newly created directories always + * inherit the gid from the parent directory. Verify that the + * directory is owned by gid 10000, not by gid 11000. + */ + if (!expected_uid_gid(open_tree_fd, DIR1, 0, 10000, 10000)) + die("failure: check ownership"); + + if (!expected_uid_gid(open_tree_fd, FILE2, 0, 10000, 10000)) + die("failure: check ownership"); + + if (!expected_uid_gid(open_tree_fd, CHRDEV1, 0, 10000, 10000)) + die("failure: check ownership"); + + if (unlinkat(open_tree_fd, FILE1, 0)) + die("failure: delete"); + + if (unlinkat(open_tree_fd, DIR1, AT_REMOVEDIR)) + die("failure: delete"); + + if (unlinkat(open_tree_fd, FILE2, 0)) + die("failure: delete"); + + if (unlinkat(open_tree_fd, CHRDEV1, 0)) + die("failure: delete"); + + /* create tmpfile via filesystem tmpfile api */ + if (supported) { + tmpfile_fd = openat(open_tree_fd, ".", O_TMPFILE | O_RDWR, S_IXGRP | S_ISGID); + if (tmpfile_fd < 0) + die("failure: create"); + /* link the temporary file into the filesystem, making it permanent */ + snprintf(path, PATH_MAX, "/proc/self/fd/%d", tmpfile_fd); + if (linkat(AT_FDCWD, path, open_tree_fd, FILE3, AT_SYMLINK_FOLLOW)) + die("failure: linkat"); + if (close(tmpfile_fd)) + die("failure: close"); + if (is_setgid(open_tree_fd, FILE3, 0)) + die("failure: is_setgid"); + if (is_ixgrp(open_tree_fd, FILE3, 0)) + die("failure: is_ixgrp"); + if (!expected_uid_gid(open_tree_fd, FILE3, 0, 10000, 10000)) + die("failure: check ownership"); + if (unlinkat(open_tree_fd, FILE3, 0)) + die("failure: delete"); + } + + exit(EXIT_SUCCESS); + } + if (wait_for_pid(pid)) + goto out; + + fret = 0; + log_debug("Ran test"); +out: + safe_close(attr.userns_fd); + safe_close(file1_fd); + safe_close(open_tree_fd); + + return fret; +} + +static int setgid_create_umask_idmapped_in_userns(const struct vfstest_info *info) +{ + int fret = -1; + int file1_fd = -EBADF, open_tree_fd = -EBADF; + struct mount_attr attr = { + .attr_set = MOUNT_ATTR_IDMAP, + }; + pid_t pid; + int tmpfile_fd = -EBADF; + bool supported = false; + char path[PATH_MAX]; + mode_t mode; + + if (!caps_supported()) + return 0; + + if (fchmod(info->t_dir1_fd, S_IRUSR | + S_IWUSR | + S_IRGRP | + S_IWGRP | + S_IROTH | + S_IWOTH | + S_IXUSR | + S_IXGRP | + S_IXOTH | + S_ISGID), 0) { + log_stderr("failure: fchmod"); + goto out; + } + + /* Verify that the sid bits got raised. */ + if (!is_setgid(info->t_dir1_fd, "", AT_EMPTY_PATH)) { + log_stderr("failure: is_setgid"); + goto out; + } + + /* Changing mount properties on a detached mount. */ + attr.userns_fd = get_userns_fd(0, 10000, 10000); + if (attr.userns_fd < 0) { + log_stderr("failure: get_userns_fd"); + goto out; + } + + open_tree_fd = sys_open_tree(info->t_dir1_fd, "", + AT_EMPTY_PATH | + AT_NO_AUTOMOUNT | + AT_SYMLINK_NOFOLLOW | + OPEN_TREE_CLOEXEC | + OPEN_TREE_CLONE); + if (open_tree_fd < 0) { + log_stderr("failure: sys_open_tree"); + goto out; + } + + if (sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr))) { + log_stderr("failure: sys_mount_setattr"); + goto out; + } + + supported = openat_tmpfile_supported(open_tree_fd); + + /* Only umask with S_IXGRP because inode strip S_ISGID will check mode + * whether has group execute or search permission. + */ + umask(S_IXGRP); + mode = umask(S_IXGRP); + if (!(mode & S_IXGRP)) + die("failure: umask"); + + /* + * Below we verify that setgid inheritance for a newly created file or + * directory works correctly. As part of this we need to verify that + * newly created files or directories inherit their gid from their + * parent directory. So we change the parent directorie's gid to 1000 + * and create a file with fs{g,u}id 0 and verify that the newly created + * file and directory inherit gid 1000, not 0. + */ + if (fchownat(info->t_dir1_fd, "", -1, 1000, AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) { + log_stderr("failure: fchownat"); + goto out; + } + + pid = fork(); + if (pid < 0) { + log_stderr("failure: fork"); + goto out; + } + if (pid == 0) { + if (!caps_supported()) { + log_debug("skip: capability library not installed"); + exit(EXIT_SUCCESS); + } + + if (!switch_userns(attr.userns_fd, 0, 0, false)) + die("failure: switch_userns"); + + if (!caps_down_fsetid()) + die("failure: caps_down_fsetid"); + + /* create regular file via open() */ + file1_fd = openat(open_tree_fd, FILE1, O_CREAT | O_EXCL | O_CLOEXEC, S_IXGRP | S_ISGID); + if (file1_fd < 0) + die("failure: create"); + + /* Neither in_group_p() nor capable_wrt_inode_uidgid() so setgid + * bit needs to be stripped. + */ + if (is_setgid(open_tree_fd, FILE1, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(open_tree_fd, FILE1, 0)) + die("failure: is_ixgrp"); + + /* create directory */ + if (mkdirat(open_tree_fd, DIR1, 0000)) + die("failure: create"); + + if (xfs_irix_sgid_inherit_enabled(info->t_fstype)) { + /* We're not in_group_p(). */ + if (is_setgid(open_tree_fd, DIR1, 0)) + die("failure: is_setgid"); + } else { + /* Directories always inherit the setgid bit. */ + if (!is_setgid(open_tree_fd, DIR1, 0)) + die("failure: is_setgid"); + } + + if (is_ixgrp(open_tree_fd, DIR1, 0)) + die("failure: is_ixgrp"); + + /* create a special file via mknodat() vfs_create */ + if (mknodat(open_tree_fd, FILE2, S_IFREG | S_ISGID | S_IXGRP, 0)) + die("failure: mknodat"); + + if (is_setgid(open_tree_fd, FILE2, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(open_tree_fd, FILE2, 0)) + die("failure: is_ixgrp"); + + /* create a whiteout device via mknodat() vfs_mknod */ + if (mknodat(open_tree_fd, CHRDEV1, S_IFCHR | S_ISGID | S_IXGRP, 0)) + die("failure: mknodat"); + + if (is_setgid(open_tree_fd, CHRDEV1, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(open_tree_fd, CHRDEV1, 0)) + die("failure: is_ixgrp"); + + /* + * In setgid directories newly created files always inherit the + * gid from the parent directory. Verify that the file is owned + * by gid 1000, not by gid 0. + */ + if (!expected_uid_gid(open_tree_fd, FILE1, 0, 0, 1000)) + die("failure: check ownership"); + + /* + * In setgid directories newly created directories always + * inherit the gid from the parent directory. Verify that the + * directory is owned by gid 1000, not by gid 0. + */ + if (!expected_uid_gid(open_tree_fd, DIR1, 0, 0, 1000)) + die("failure: check ownership"); + + if (!expected_uid_gid(open_tree_fd, FILE2, 0, 0, 1000)) + die("failure: check ownership"); + + if (!expected_uid_gid(open_tree_fd, CHRDEV1, 0, 0, 1000)) + die("failure: check ownership"); + + if (unlinkat(open_tree_fd, FILE1, 0)) + die("failure: delete"); + + if (unlinkat(open_tree_fd, DIR1, AT_REMOVEDIR)) + die("failure: delete"); + + if (unlinkat(open_tree_fd, FILE2, 0)) + die("failure: delete"); + + if (unlinkat(open_tree_fd, CHRDEV1, 0)) + die("failure: delete"); + + /* create tmpfile via filesystem tmpfile api */ + if (supported) { + tmpfile_fd = openat(open_tree_fd, ".", O_TMPFILE | O_RDWR, S_IXGRP | S_ISGID); + if (tmpfile_fd < 0) + die("failure: create"); + /* link the temporary file into the filesystem, making it permanent */ + snprintf(path, PATH_MAX, "/proc/self/fd/%d", tmpfile_fd); + if (linkat(AT_FDCWD, path, open_tree_fd, FILE3, AT_SYMLINK_FOLLOW)) + die("failure: linkat"); + if (close(tmpfile_fd)) + die("failure: close"); + if (is_setgid(open_tree_fd, FILE3, 0)) + die("failure: is_setgid"); + if (is_ixgrp(open_tree_fd, FILE3, 0)) + die("failure: is_ixgrp"); + if (!expected_uid_gid(open_tree_fd, FILE3, 0, 0, 1000)) + die("failure: check ownership"); + if (unlinkat(open_tree_fd, FILE3, 0)) + die("failure: delete"); + } + + exit(EXIT_SUCCESS); + } + if (wait_for_pid(pid)) + goto out; + + fret = 0; + log_debug("Ran test"); +out: + safe_close(attr.userns_fd); + safe_close(file1_fd); + safe_close(open_tree_fd); + + return fret; +} + static const struct test_struct t_idmapped_mounts[] = { { acls, true, "posix acls on regular mounts", }, { create_in_userns, true, "create operations in user namespace", }, @@ -7745,3 +8164,13 @@ const struct test_suite s_setxattr_fix_705191b03d50 = { .tests = t_setxattr_fix_705191b03d50, .nr_tests = ARRAY_SIZE(t_setxattr_fix_705191b03d50), }; + +static const struct test_struct t_setgid_create_umask_idmapped_mounts[] = { + { setgid_create_umask_idmapped, T_REQUIRE_IDMAPPED_MOUNTS, "create operations by using umask in directories with setgid bit set on idmapped mount", }, + { setgid_create_umask_idmapped_in_userns, T_REQUIRE_IDMAPPED_MOUNTS, "create operations by using umask in directories with setgid bit set on idmapped mount inside userns", }, +}; + +const struct test_suite s_setgid_create_umask_idmapped_mounts = { + .tests = t_setgid_create_umask_idmapped_mounts, + .nr_tests = ARRAY_SIZE(t_setgid_create_umask_idmapped_mounts), +}; diff --git a/src/vfs/idmapped-mounts.h b/src/vfs/idmapped-mounts.h index ff21ea2c..a9fb31ea 100644 --- a/src/vfs/idmapped-mounts.h +++ b/src/vfs/idmapped-mounts.h @@ -14,5 +14,6 @@ extern const struct test_suite s_fscaps_in_ancestor_userns; extern const struct test_suite s_nested_userns; extern const struct test_suite s_setattr_fix_968219708108; extern const struct test_suite s_setxattr_fix_705191b03d50; +extern const struct test_suite s_setgid_create_umask_idmapped_mounts; #endif /* __IDMAPPED_MOUNTS_H */ diff --git a/src/vfs/utils.c b/src/vfs/utils.c index 1388edda..6db7a11d 100644 --- a/src/vfs/utils.c +++ b/src/vfs/utils.c @@ -809,6 +809,20 @@ bool is_sticky(int dfd, const char *path, int flags) return (st.st_mode & S_ISVTX) > 0; } +/*is_ixgrp - check whether file or directory is S_IXGRP */ +bool is_ixgrp(int dfd, const char *path, int flags) +{ + int ret; + struct stat st; + + ret = fstatat(dfd, path, &st, flags); + if (ret < 0) + return false; + + errno = 0; /* Don't report misleading errno. */ + return (st.st_mode & S_IXGRP); +} + bool switch_resids(uid_t uid, gid_t gid) { if (setresgid(gid, gid, gid)) diff --git a/src/vfs/utils.h b/src/vfs/utils.h index 7fb702fd..c0dbe370 100644 --- a/src/vfs/utils.h +++ b/src/vfs/utils.h @@ -368,6 +368,7 @@ extern bool expected_file_size(int dfd, const char *path, int flags, extern bool is_setid(int dfd, const char *path, int flags); extern bool is_setgid(int dfd, const char *path, int flags); extern bool is_sticky(int dfd, const char *path, int flags); +extern bool is_ixgrp(int dfd, const char *path, int flags); extern bool openat_tmpfile_supported(int dirfd); #endif /* __IDMAP_UTILS_H */ diff --git a/src/vfs/vfstest.c b/src/vfs/vfstest.c index 29ac0bec..e928a1f5 100644 --- a/src/vfs/vfstest.c +++ b/src/vfs/vfstest.c @@ -1733,6 +1733,186 @@ out: return fret; } +/* The current_umask() is stripped from the mode directly in the vfs if the + * filesystem either doesn't support acls or the filesystem has been + * mounted without posic acl support. + * + * If the filesystem does support acls then current_umask() stripping is + * deferred to posix_acl_create(). So when the filesystem calls + * posix_acl_create() and there are no acls set or not supported then + * current_umask() will be stripped. + * + * Use umask(S_IXGRP) to check whether inode strip S_ISGID works correctly. + * + * test for commit ac6800e279a2 ("fs: Add missing umask strip in vfs_tmpfile") + * and 1639a49ccdce ("fs: move S_ISGID stripping into the vfs_*() helpers"). + */ + +static int setgid_create_umask(const struct vfstest_info *info) +{ + int fret = -1; + int file1_fd = -EBADF; + int tmpfile_fd = -EBADF; + pid_t pid; + bool supported = false; + mode_t mode; + + if (!caps_supported()) + return 0; + + if (fchmod(info->t_dir1_fd, S_IRUSR | + S_IWUSR | + S_IRGRP | + S_IWGRP | + S_IROTH | + S_IWOTH | + S_IXUSR | + S_IXGRP | + S_IXOTH | + S_ISGID), 0) { + log_stderr("failure: fchmod"); + goto out; + } + + /* Verify that the setgid bit got raised. */ + if (!is_setgid(info->t_dir1_fd, "", AT_EMPTY_PATH)) { + log_stderr("failure: is_setgid"); + goto out; + } + + supported = openat_tmpfile_supported(info->t_dir1_fd); + + umask(S_IXGRP); + mode = umask(S_IXGRP); + if (!(mode & S_IXGRP)) + die("failure: umask"); + + pid = fork(); + if (pid < 0) { + log_stderr("failure: fork"); + goto out; + } + if (pid == 0) { + if (!switch_ids(0, 10000)) + die("failure: switch_ids"); + + if (!caps_down_fsetid()) + die("failure: caps_down_fsetid"); + + /* create regular file via open() */ + file1_fd = openat(info->t_dir1_fd, FILE1, O_CREAT | O_EXCL | O_CLOEXEC, S_IXGRP | S_ISGID); + if (file1_fd < 0) + die("failure: create"); + + /* Neither in_group_p() nor capable_wrt_inode_uidgid() so setgid + * bit needs to be stripped. + */ + if (is_setgid(info->t_dir1_fd, FILE1, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(info->t_dir1_fd, FILE1, 0)) + die("failure: is_ixgrp"); + + if (mkdirat(info->t_dir1_fd, DIR1, 0000)) + die("failure: create"); + + if (xfs_irix_sgid_inherit_enabled(info->t_fstype)) { + /* We're not in_group_p(). */ + if (is_setgid(info->t_dir1_fd, DIR1, 0)) + die("failure: is_setgid"); + } else { + /* Directories always inherit the setgid bit. */ + if (!is_setgid(info->t_dir1_fd, DIR1, 0)) + die("failure: is_setgid"); + } + + if (is_ixgrp(info->t_dir1_fd, DIR1, 0)) + die("failure: is_ixgrp"); + + /* create a special file via mknodat() vfs_create */ + if (mknodat(info->t_dir1_fd, FILE2, S_IFREG | S_ISGID | S_IXGRP, 0)) + die("failure: mknodat"); + + if (is_setgid(info->t_dir1_fd, FILE2, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(info->t_dir1_fd, FILE2, 0)) + die("failure: is_ixgrp"); + + /* create a character device via mknodat() vfs_mknod */ + if (mknodat(info->t_dir1_fd, CHRDEV1, S_IFCHR | S_ISGID | S_IXGRP, makedev(5, 1))) + die("failure: mknodat"); + + if (is_setgid(info->t_dir1_fd, CHRDEV1, 0)) + die("failure: is_setgid"); + + if (is_ixgrp(info->t_dir1_fd, CHRDEV1, 0)) + die("failure: is_ixgrp"); + + /* + * In setgid directories newly created files always inherit the + * gid from the parent directory. Verify that the file is owned + * by gid 0, not by gid 10000. + */ + if (!expected_uid_gid(info->t_dir1_fd, FILE1, 0, 0, 0)) + die("failure: check ownership"); + + /* + * In setgid directories newly created directories always + * inherit the gid from the parent directory. Verify that the + * directory is owned by gid 0, not by gid 10000. + */ + if (!expected_uid_gid(info->t_dir1_fd, DIR1, 0, 0, 0)) + die("failure: check ownership"); + + if (!expected_uid_gid(info->t_dir1_fd, FILE2, 0, 0, 0)) + die("failure: check ownership"); + + if (!expected_uid_gid(info->t_dir1_fd, CHRDEV1, 0, 0, 0)) + die("failure: check ownership"); + + if (unlinkat(info->t_dir1_fd, FILE1, 0)) + die("failure: delete"); + + if (unlinkat(info->t_dir1_fd, DIR1, AT_REMOVEDIR)) + die("failure: delete"); + + if (unlinkat(info->t_dir1_fd, FILE2, 0)) + die("failure: delete"); + + if (unlinkat(info->t_dir1_fd, CHRDEV1, 0)) + die("failure: delete"); + + /* create tmpfile via filesystem tmpfile api */ + if (supported) { + tmpfile_fd = openat(info->t_dir1_fd, ".", O_TMPFILE | O_RDWR, S_IXGRP | S_ISGID); + if (tmpfile_fd < 0) + die("failure: create"); + /* link the temporary file into the filesystem, making it permanent */ + if (linkat(tmpfile_fd, "", info->t_dir1_fd, FILE3, AT_EMPTY_PATH)) + die("failure: linkat"); + if (close(tmpfile_fd)) + die("failure: close"); + if (is_setgid(info->t_dir1_fd, FILE3, 0)) + die("failure: is_setgid"); + if (is_ixgrp(info->t_dir1_fd, FILE3, 0)) + die("failure: is_ixgrp"); + if (unlinkat(info->t_dir1_fd, FILE3, 0)) + die("failure: delete"); + } + + exit(EXIT_SUCCESS); + } + if (wait_for_pid(pid)) + goto out; + + fret = 0; + log_debug("Ran test"); +out: + safe_close(file1_fd); + return fret; +} + static int setattr_truncate(const struct vfstest_info *info) { int fret = -1; @@ -1807,6 +1987,7 @@ static void usage(void) fprintf(stderr, "--test-btrfs Run btrfs specific idmapped mount testsuite\n"); fprintf(stderr, "--test-setattr-fix-968219708108 Run setattr regression tests\n"); fprintf(stderr, "--test-setxattr-fix-705191b03d50 Run setxattr regression tests\n"); + fprintf(stderr, "--test-setgid-create-umask Run setgid with umask tests\n"); _exit(EXIT_SUCCESS); } @@ -1825,6 +2006,7 @@ static const struct option longopts[] = { {"test-btrfs", no_argument, 0, 'b'}, {"test-setattr-fix-968219708108", no_argument, 0, 'i'}, {"test-setxattr-fix-705191b03d50", no_argument, 0, 'j'}, + {"test-setgid-create-umask", no_argument, 0, 'u'}, {NULL, 0, 0, 0}, }; @@ -1850,6 +2032,15 @@ static const struct test_suite s_basic = { .nr_tests = ARRAY_SIZE(t_basic), }; +static const struct test_struct t_setgid_create_umask[] = { + { setgid_create_umask, 0, "create operations in directories with setgid bit set under umask", }, +}; + +static const struct test_suite s_setgid_create_umask = { + .tests = t_setgid_create_umask, + .nr_tests = ARRAY_SIZE(t_setgid_create_umask), +}; + static bool run_test(struct vfstest_info *info, const struct test_struct suite[], size_t suite_size) { int i; @@ -1947,7 +2138,8 @@ int main(int argc, char *argv[]) bool idmapped_mounts_supported = false, test_btrfs = false, test_core = false, test_fscaps_regression = false, test_nested_userns = false, test_setattr_fix_968219708108 = false, - test_setxattr_fix_705191b03d50 = false; + test_setxattr_fix_705191b03d50 = false, + test_setgid_create_umask = false; init_vfstest_info(&info); @@ -1989,6 +2181,9 @@ int main(int argc, char *argv[]) case 'j': test_setxattr_fix_705191b03d50 = true; break; + case 'u': + test_setgid_create_umask = true; + break; case 'h': /* fallthrough */ default: @@ -2066,6 +2261,14 @@ int main(int argc, char *argv[]) !run_suite(&info, &s_setxattr_fix_705191b03d50)) goto out; + if (test_setgid_create_umask) { + if (!run_suite(&info, &s_setgid_create_umask)) + goto out; + + if (!run_suite(&info, &s_setgid_create_umask_idmapped_mounts)) + goto out; + } + fret = EXIT_SUCCESS; out: diff --git a/tests/generic/998 b/tests/generic/998 new file mode 100755 index 00000000..5f736b6d --- /dev/null +++ b/tests/generic/998 @@ -0,0 +1,46 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2022 Fujitsu Limited. All Rights Reserved. +# +# FS QA Test No. 998 +# +# Test S_ISGID stripping whether works correctly when call process +# uses umask(S_IXGRP). +# +# It is also a regression test for +# commit ac6800e279a2 ("fs: Add missing umask strip in vfs_tmpfile") +# commit 1639a49ccdce ("fs: move S_ISGID stripping into the vfs_*() helpers") + +. ./common/preamble +_begin_fstest auto quick cap idmapped mount perms rw unlink + +# Import common functions. +. ./common/filter + +# real QA test starts here + +_supported_fs generic +_require_test +_require_scratch +_fixed_by_kernel_commit ac6800e279a2 \ + "fs: Add missing umask strip in vfs_tmpfile" \ +1639a49ccdce "fs: move S_ISGID stripping into the vfs_*() helpers" + +_scratch_mkfs >$seqres.full 2>&1 + +$here/src/vfs/vfstest --test-setgid-create-umask \ + --device "$TEST_DEV" --mount "$TEST_DIR" --fstype "$FSTYP" + +export MOUNT_OPTIONS="-o noacl" + +# Also test S_ISGID stripping whether works correctly on underflying filesystem +# that supports noacl feature. +# noacl will earse acl flag in superblock, so kernel will use current_umask in +# vfs directly instead of calling posix_acl_create on underflying filesystem. +_try_scratch_mount >>$seqres.full 2>&1 && \ + $here/src/vfs/vfstest --test-setgid-create-umask \ + --device "$SCRATCH_DEV" --mount "$SCRATCH_MNT" --fstype "$FSTYP" + +echo "Silence is golden" +status=0 +exit diff --git a/tests/generic/998.out b/tests/generic/998.out new file mode 100644 index 00000000..d2679ae0 --- /dev/null +++ b/tests/generic/998.out @@ -0,0 +1,2 @@ +QA output created by 998 +Silence is golden