summaryrefslogtreecommitdiffstats
path: root/tools/testing/selftests/filesystems/nsfs/iterate_mntns.c
blob: a3d8015897e98688f205a5aa217288ffdc3d71ce (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
// SPDX-License-Identifier: GPL-2.0-or-later
// Copyright (c) 2024 Christian Brauner <brauner@kernel.org>

#define _GNU_SOURCE
#include <fcntl.h>
#include <linux/auto_dev-ioctl.h>
#include <linux/errno.h>
#include <sched.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/mount.h>
#include <unistd.h>

#include "../../kselftest_harness.h"

#define MNT_NS_COUNT 11
#define MNT_NS_LAST_INDEX 10

struct mnt_ns_info {
	__u32 size;
	__u32 nr_mounts;
	__u64 mnt_ns_id;
};

#define MNT_NS_INFO_SIZE_VER0 16 /* size of first published struct */

/* Get information about namespace. */
#define NS_MNT_GET_INFO _IOR(0xb7, 10, struct mnt_ns_info)
/* Get next namespace. */
#define NS_MNT_GET_NEXT _IOR(0xb7, 11, struct mnt_ns_info)
/* Get previous namespace. */
#define NS_MNT_GET_PREV _IOR(0xb7, 12, struct mnt_ns_info)

FIXTURE(iterate_mount_namespaces) {
	int fd_mnt_ns[MNT_NS_COUNT];
	__u64 mnt_ns_id[MNT_NS_COUNT];
};

FIXTURE_SETUP(iterate_mount_namespaces)
{
	for (int i = 0; i < MNT_NS_COUNT; i++)
		self->fd_mnt_ns[i] = -EBADF;

	/*
	 * Creating a new user namespace let's us guarantee that we only see
	 * mount namespaces that we did actually create.
	 */
	ASSERT_EQ(unshare(CLONE_NEWUSER), 0);

	for (int i = 0; i < MNT_NS_COUNT; i++) {
		struct mnt_ns_info info = {};

		ASSERT_EQ(unshare(CLONE_NEWNS), 0);
		self->fd_mnt_ns[i] = open("/proc/self/ns/mnt", O_RDONLY | O_CLOEXEC);
		ASSERT_GE(self->fd_mnt_ns[i], 0);
		ASSERT_EQ(ioctl(self->fd_mnt_ns[i], NS_MNT_GET_INFO, &info), 0);
		self->mnt_ns_id[i] = info.mnt_ns_id;
	}
}

FIXTURE_TEARDOWN(iterate_mount_namespaces)
{
	for (int i = 0; i < MNT_NS_COUNT; i++) {
		if (self->fd_mnt_ns[i] < 0)
			continue;
		ASSERT_EQ(close(self->fd_mnt_ns[i]), 0);
	}
}

TEST_F(iterate_mount_namespaces, iterate_all_forward)
{
	int fd_mnt_ns_cur, count = 0;

	fd_mnt_ns_cur = fcntl(self->fd_mnt_ns[0], F_DUPFD_CLOEXEC);
	ASSERT_GE(fd_mnt_ns_cur, 0);

	for (;; count++) {
		struct mnt_ns_info info = {};
		int fd_mnt_ns_next;

		fd_mnt_ns_next = ioctl(fd_mnt_ns_cur, NS_MNT_GET_NEXT, &info);
		if (fd_mnt_ns_next < 0 && errno == ENOENT)
			break;
		ASSERT_GE(fd_mnt_ns_next, 0);
		ASSERT_EQ(close(fd_mnt_ns_cur), 0);
		fd_mnt_ns_cur = fd_mnt_ns_next;
	}
	ASSERT_EQ(count, MNT_NS_LAST_INDEX);
}

TEST_F(iterate_mount_namespaces, iterate_all_backwards)
{
	int fd_mnt_ns_cur, count = 0;

	fd_mnt_ns_cur = fcntl(self->fd_mnt_ns[MNT_NS_LAST_INDEX], F_DUPFD_CLOEXEC);
	ASSERT_GE(fd_mnt_ns_cur, 0);

	for (;; count++) {
		struct mnt_ns_info info = {};
		int fd_mnt_ns_prev;

		fd_mnt_ns_prev = ioctl(fd_mnt_ns_cur, NS_MNT_GET_PREV, &info);
		if (fd_mnt_ns_prev < 0 && errno == ENOENT)
			break;
		ASSERT_GE(fd_mnt_ns_prev, 0);
		ASSERT_EQ(close(fd_mnt_ns_cur), 0);
		fd_mnt_ns_cur = fd_mnt_ns_prev;
	}
	ASSERT_EQ(count, MNT_NS_LAST_INDEX);
}

TEST_F(iterate_mount_namespaces, iterate_forward)
{
	int fd_mnt_ns_cur;

	ASSERT_EQ(setns(self->fd_mnt_ns[0], CLONE_NEWNS), 0);

	fd_mnt_ns_cur = self->fd_mnt_ns[0];
	for (int i = 1; i < MNT_NS_COUNT; i++) {
		struct mnt_ns_info info = {};
		int fd_mnt_ns_next;

		fd_mnt_ns_next = ioctl(fd_mnt_ns_cur, NS_MNT_GET_NEXT, &info);
		ASSERT_GE(fd_mnt_ns_next, 0);
		ASSERT_EQ(close(fd_mnt_ns_cur), 0);
		fd_mnt_ns_cur = fd_mnt_ns_next;
		ASSERT_EQ(info.mnt_ns_id, self->mnt_ns_id[i]);
	}
}

TEST_F(iterate_mount_namespaces, iterate_backward)
{
	int fd_mnt_ns_cur;

	ASSERT_EQ(setns(self->fd_mnt_ns[MNT_NS_LAST_INDEX], CLONE_NEWNS), 0);

	fd_mnt_ns_cur = self->fd_mnt_ns[MNT_NS_LAST_INDEX];
	for (int i = MNT_NS_LAST_INDEX - 1; i >= 0; i--) {
		struct mnt_ns_info info = {};
		int fd_mnt_ns_prev;

		fd_mnt_ns_prev = ioctl(fd_mnt_ns_cur, NS_MNT_GET_PREV, &info);
		ASSERT_GE(fd_mnt_ns_prev, 0);
		ASSERT_EQ(close(fd_mnt_ns_cur), 0);
		fd_mnt_ns_cur = fd_mnt_ns_prev;
		ASSERT_EQ(info.mnt_ns_id, self->mnt_ns_id[i]);
	}
}

TEST_F(iterate_mount_namespaces, nfs_valid_ioctl)
{
	ASSERT_NE(ioctl(self->fd_mnt_ns[0], AUTOFS_DEV_IOCTL_OPENMOUNT, NULL), 0);
	ASSERT_EQ(errno, ENOTTY);

	ASSERT_NE(ioctl(self->fd_mnt_ns[0], AUTOFS_DEV_IOCTL_CLOSEMOUNT, NULL), 0);
	ASSERT_EQ(errno, ENOTTY);

	ASSERT_NE(ioctl(self->fd_mnt_ns[0], AUTOFS_DEV_IOCTL_READY, NULL), 0);
	ASSERT_EQ(errno, ENOTTY);
}

TEST_HARNESS_MAIN