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 pointing #! script interpreter to self doesn't recurse. */
17#include <errno.h>
18#include <sched.h>
19#include <stdio.h>
20#include <string.h>
21#include <sys/types.h>
22#include <sys/stat.h>
23#include <fcntl.h>
24#include <sys/mount.h>
25#include <unistd.h>
26#include "../kselftest.h"
27
28int main(void)
29{
30	int fd, rv;
31
32	ksft_print_header();
33	ksft_set_plan(1);
34
35	if (unshare(CLONE_NEWNS) == -1) {
36		if (errno == ENOSYS || errno == EPERM) {
37			ksft_test_result_skip("error: unshare, errno %d\n", errno);
38			ksft_finished();
39		}
40		ksft_exit_fail_msg("error: unshare, errno %d\n", errno);
41	}
42
43	if (mount(NULL, "/", NULL, MS_PRIVATE | MS_REC, NULL) == -1)
44		ksft_exit_fail_msg("error: mount '/', errno %d\n", errno);
45
46	/* Require "exec" filesystem. */
47	if (mount(NULL, "/tmp", "ramfs", 0, NULL) == -1)
48		ksft_exit_fail_msg("error: mount ramfs, errno %d\n", errno);
49
50#define FILENAME "/tmp/1"
51
52	fd = creat(FILENAME, 0700);
53	if (fd == -1)
54		ksft_exit_fail_msg("error: creat, errno %d\n", errno);
55
56#define S "#!" FILENAME "\n"
57	if (write(fd, S, strlen(S)) != strlen(S))
58		ksft_exit_fail_msg("error: write, errno %d\n", errno);
59
60	close(fd);
61
62	rv = execve(FILENAME, NULL, NULL);
63	ksft_test_result(rv == -1 && errno == ELOOP,
64			 "execve failed as expected (ret %d, errno %d)\n", rv, errno);
65	ksft_finished();
66}
67