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 #include "../kselftest.h" 27 28 int main(void) 29 { 30 int fd; 31 32 // Setting up kselftest framework 33 ksft_print_header(); 34 ksft_set_plan(1); 35 36 // Check if test is run as root 37 if (geteuid()) { 38 ksft_exit_skip("This test needs root to run!\n"); 39 return 1; 40 } 41 42 if (unshare(CLONE_NEWNS) == -1) { 43 if (errno == ENOSYS || errno == EPERM) { 44 ksft_exit_skip("unshare() error: unshare, errno %d\n", errno); 45 } else { 46 ksft_exit_fail_msg("unshare() error: unshare, errno %d\n", errno); 47 } 48 } 49 50 if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) == -1) { 51 ksft_exit_fail_msg("mount() error: Root filesystem private mount: Fail %d\n", errno); 52 } 53 54 /* Our heroes: 1 root inode, 1 O_TMPFILE inode, 1 permanent inode. */ 55 if (mount(NULL, "/tmp", "tmpfs", 0, "nr_inodes=3") == -1) { 56 ksft_exit_fail_msg("mount() error: Mounting tmpfs on /tmp: Fail %d\n", errno); 57 } 58 59 fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600); 60 if (fd == -1) { 61 ksft_exit_fail_msg("openat() error: Open first temporary file: Fail %d\n", errno); 62 } 63 64 if (linkat(fd, "", AT_FDCWD, "/tmp/1", AT_EMPTY_PATH) == -1) { 65 ksft_exit_fail_msg("linkat() error: Linking the temporary file: Fail %d\n", errno); 66 /* Ensure fd is closed on failure */ 67 close(fd); 68 } 69 close(fd); 70 71 fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600); 72 if (fd == -1) { 73 ksft_exit_fail_msg("openat() error: Opening the second temporary file: Fail %d\n", errno); 74 } 75 ksft_test_result_pass(" "); 76 ksft_exit_pass(); 77 return 0; 78 } 79