1/* SPDX-License-Identifier: GPL-2.0 */
2
3#define _GNU_SOURCE
4#include <errno.h>
5#include <sched.h>
6#include <signal.h>
7#include <stdio.h>
8#include <stdlib.h>
9#include <string.h>
10#include <unistd.h>
11#include <linux/sched.h>
12#include <linux/types.h>
13#include <sys/syscall.h>
14#include <sys/wait.h>
15
16#include "../kselftest.h"
17#include "clone3_selftests.h"
18
19#ifndef CLONE_CLEAR_SIGHAND
20#define CLONE_CLEAR_SIGHAND 0x100000000ULL
21#endif
22
23static void nop_handler(int signo)
24{
25}
26
27static int wait_for_pid(pid_t pid)
28{
29	int status, ret;
30
31again:
32	ret = waitpid(pid, &status, 0);
33	if (ret == -1) {
34		if (errno == EINTR)
35			goto again;
36
37		return -1;
38	}
39
40	if (!WIFEXITED(status))
41		return -1;
42
43	return WEXITSTATUS(status);
44}
45
46static void test_clone3_clear_sighand(void)
47{
48	int ret;
49	pid_t pid;
50	struct __clone_args args = {};
51	struct sigaction act;
52
53	/*
54	 * Check that CLONE_CLEAR_SIGHAND and CLONE_SIGHAND are mutually
55	 * exclusive.
56	 */
57	args.flags |= CLONE_CLEAR_SIGHAND | CLONE_SIGHAND;
58	args.exit_signal = SIGCHLD;
59	pid = sys_clone3(&args, sizeof(args));
60	if (pid > 0)
61		ksft_exit_fail_msg(
62			"clone3(CLONE_CLEAR_SIGHAND | CLONE_SIGHAND) succeeded\n");
63
64	act.sa_handler = nop_handler;
65	ret = sigemptyset(&act.sa_mask);
66	if (ret < 0)
67		ksft_exit_fail_msg("%s - sigemptyset() failed\n",
68				   strerror(errno));
69
70	act.sa_flags = 0;
71
72	/* Register signal handler for SIGUSR1 */
73	ret = sigaction(SIGUSR1, &act, NULL);
74	if (ret < 0)
75		ksft_exit_fail_msg(
76			"%s - sigaction(SIGUSR1, &act, NULL) failed\n",
77			strerror(errno));
78
79	/* Register signal handler for SIGUSR2 */
80	ret = sigaction(SIGUSR2, &act, NULL);
81	if (ret < 0)
82		ksft_exit_fail_msg(
83			"%s - sigaction(SIGUSR2, &act, NULL) failed\n",
84			strerror(errno));
85
86	/* Check that CLONE_CLEAR_SIGHAND works. */
87	args.flags = CLONE_CLEAR_SIGHAND;
88	pid = sys_clone3(&args, sizeof(args));
89	if (pid < 0)
90		ksft_exit_fail_msg("%s - clone3(CLONE_CLEAR_SIGHAND) failed\n",
91				   strerror(errno));
92
93	if (pid == 0) {
94		ret = sigaction(SIGUSR1, NULL, &act);
95		if (ret < 0)
96			exit(EXIT_FAILURE);
97
98		if (act.sa_handler != SIG_DFL)
99			exit(EXIT_FAILURE);
100
101		ret = sigaction(SIGUSR2, NULL, &act);
102		if (ret < 0)
103			exit(EXIT_FAILURE);
104
105		if (act.sa_handler != SIG_DFL)
106			exit(EXIT_FAILURE);
107
108		exit(EXIT_SUCCESS);
109	}
110
111	ret = wait_for_pid(pid);
112	if (ret)
113		ksft_exit_fail_msg(
114			"Failed to clear signal handler for child process\n");
115
116	ksft_test_result_pass("Cleared signal handlers for child process\n");
117}
118
119int main(int argc, char **argv)
120{
121	ksft_print_header();
122	ksft_set_plan(1);
123	test_clone3_supported();
124
125	test_clone3_clear_sighand();
126
127	return ksft_exit_pass();
128}
129