1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2014 Red Hat, Inc.
4 * Copyright (C) 2021 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
5 */
6
7/*\
8 * [Description]
9 *
10 * Tests an unbindable mount: unbindable mount is an unbindable
11 * private mount.
12 *
13 * - Creates directories DIRA, DIRB and files DIRA/"A", DIRB/"B"
14 * - Unshares mount namespace and makes it private (so mounts/umounts have no
15 *   effect on a real system)
16 * - Bind mounts directory DIRA to DIRA
17 * - Makes directory DIRA unbindable
18 * - Check if bind mount unbindable DIRA to DIRB fails as expected
19 */
20
21#include <sys/wait.h>
22#include <sys/mount.h>
23#include "mountns.h"
24#include "tst_test.h"
25#include "lapi/sched.h"
26
27static void run(void)
28{
29	SAFE_UNSHARE(CLONE_NEWNS);
30
31	/* makes sure mounts/umounts have no effect on a real system */
32	SAFE_MOUNT("none", "/", "none", MS_REC | MS_PRIVATE, NULL);
33
34	SAFE_MOUNT(DIRA, DIRA, "none", MS_BIND, NULL);
35
36	SAFE_MOUNT("none", DIRA, "none", MS_UNBINDABLE, NULL);
37
38	if (mount(DIRA, DIRB, "none", MS_BIND, NULL) == -1) {
39		tst_res(TPASS, "unbindable mount passed");
40	} else {
41		SAFE_UMOUNT(DIRB);
42		tst_res(TFAIL, "unbindable mount faled");
43	}
44
45	SAFE_UMOUNT(DIRA);
46}
47
48static void setup(void)
49{
50	create_folders();
51}
52
53static void cleanup(void)
54{
55	umount_folders();
56}
57
58static struct tst_test test = {
59	.setup = setup,
60	.cleanup = cleanup,
61	.test_all = run,
62	.needs_root = 1,
63	.needs_tmpdir = 1,
64	.needs_kconfigs = (const char *[]) {
65		"CONFIG_USER_NS",
66		NULL,
67	},
68};
69