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 } 68