1 /*
2 * Copyright (c) 2019 Alexey Dobriyan <adobriyan@gmail.com>
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16 /* Test that open(O_TMPFILE), linkat() doesn't screw accounting. */
17 #include <errno.h>
18 #include <sched.h>
19 #include <stdio.h>
20 #include <sys/types.h>
21 #include <sys/stat.h>
22 #include <fcntl.h>
23 #include <sys/mount.h>
24 #include <unistd.h>
25
26 int main(void)
27 {
28 int fd;
29
30 if (unshare(CLONE_NEWNS) == -1) {
31 if (errno == ENOSYS || errno == EPERM) {
32 fprintf(stderr, "error: unshare, errno %d\n", errno);
33 return 4;
34 }
35 fprintf(stderr, "error: unshare, errno %d\n", errno);
36 return 1;
37 }
38 if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) == -1) {
39 fprintf(stderr, "error: mount '/', errno %d\n", errno);
40 return 1;
41 }
42
43 /* Our heroes: 1 root inode, 1 O_TMPFILE inode, 1 permanent inode. */
44 if (mount(NULL, "/tmp", "tmpfs", 0, "nr_inodes=3") == -1) {
45 fprintf(stderr, "error: mount tmpfs, errno %d\n", errno);
46 return 1;
47 }
48
49 fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600);
50 if (fd == -1) {
51 fprintf(stderr, "error: open 1, errno %d\n", errno);
52 return 1;
53 }
54 if (linkat(fd, "", AT_FDCWD, "/tmp/1", AT_EMPTY_PATH) == -1) {
55 fprintf(stderr, "error: linkat, errno %d\n", errno);
56 return 1;
57 }
58 close(fd);
59
60 fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600);
61 if (fd == -1) {
62 fprintf(stderr, "error: open 2, errno %d\n", errno);
63 return 1;
64 }
65
66 return 0;
67 }