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1/*2 * Copyright (c) 2019 Alexey Dobriyan <adobriyan@gmail.com>3 *4 * Permission to use, copy, modify, and distribute this software for any5 * purpose with or without fee is hereby granted, provided that the above6 * copyright notice and this permission notice appear in all copies.7 *8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF14 * 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 26int 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}68