1// SPDX-License-Identifier: GPL-2.0
2
3/* Based on Christian Brauner's clone3() example */
4
5#define _GNU_SOURCE
6#include <errno.h>
7#include <inttypes.h>
8#include <linux/types.h>
9#include <linux/sched.h>
10#include <stdint.h>
11#include <stdio.h>
12#include <stdlib.h>
13#include <sys/syscall.h>
14#include <sys/types.h>
15#include <sys/un.h>
16#include <sys/wait.h>
17#include <unistd.h>
18#include <sched.h>
19
20#include "../kselftest.h"
21#include "clone3_selftests.h"
22
23enum test_mode {
24	CLONE3_ARGS_NO_TEST,
25	CLONE3_ARGS_ALL_0,
26	CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG,
27	CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG,
28	CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG,
29	CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG,
30};
31
32static int call_clone3(uint64_t flags, size_t size, enum test_mode test_mode)
33{
34	struct __clone_args args = {
35		.flags = flags,
36		.exit_signal = SIGCHLD,
37	};
38
39	struct clone_args_extended {
40		struct __clone_args args;
41		__aligned_u64 excess_space[2];
42	} args_ext;
43
44	pid_t pid = -1;
45	int status;
46
47	memset(&args_ext, 0, sizeof(args_ext));
48	if (size > sizeof(struct __clone_args))
49		args_ext.excess_space[1] = 1;
50
51	if (size == 0)
52		size = sizeof(struct __clone_args);
53
54	switch (test_mode) {
55	case CLONE3_ARGS_NO_TEST:
56		/*
57		 * Uses default 'flags' and 'SIGCHLD'
58		 * assignment.
59		 */
60		break;
61	case CLONE3_ARGS_ALL_0:
62		args.flags = 0;
63		args.exit_signal = 0;
64		break;
65	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG:
66		args.exit_signal = 0xbadc0ded00000000ULL;
67		break;
68	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG:
69		args.exit_signal = 0x0000000080000000ULL;
70		break;
71	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG:
72		args.exit_signal = 0x0000000000000100ULL;
73		break;
74	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG:
75		args.exit_signal = 0x00000000000000f0ULL;
76		break;
77	}
78
79	memcpy(&args_ext.args, &args, sizeof(struct __clone_args));
80
81	pid = sys_clone3((struct __clone_args *)&args_ext, size);
82	if (pid < 0) {
83		ksft_print_msg("%s - Failed to create new process\n",
84				strerror(errno));
85		return -errno;
86	}
87
88	if (pid == 0) {
89		ksft_print_msg("I am the child, my PID is %d\n", getpid());
90		_exit(EXIT_SUCCESS);
91	}
92
93	ksft_print_msg("I am the parent (%d). My child's pid is %d\n",
94			getpid(), pid);
95
96	if (waitpid(-1, &status, __WALL) < 0) {
97		ksft_print_msg("Child returned %s\n", strerror(errno));
98		return -errno;
99	}
100	if (WEXITSTATUS(status))
101		return WEXITSTATUS(status);
102
103	return 0;
104}
105
106static void test_clone3(uint64_t flags, size_t size, int expected,
107		       enum test_mode test_mode)
108{
109	int ret;
110
111	ksft_print_msg(
112		"[%d] Trying clone3() with flags %#" PRIx64 " (size %zu)\n",
113		getpid(), flags, size);
114	ret = call_clone3(flags, size, test_mode);
115	ksft_print_msg("[%d] clone3() with flags says: %d expected %d\n",
116			getpid(), ret, expected);
117	if (ret != expected)
118		ksft_test_result_fail(
119			"[%d] Result (%d) is different than expected (%d)\n",
120			getpid(), ret, expected);
121	else
122		ksft_test_result_pass(
123			"[%d] Result (%d) matches expectation (%d)\n",
124			getpid(), ret, expected);
125}
126
127int main(int argc, char *argv[])
128{
129	uid_t uid = getuid();
130
131	ksft_print_header();
132	ksft_set_plan(17);
133	test_clone3_supported();
134
135	/* Just a simple clone3() should return 0.*/
136	test_clone3(0, 0, 0, CLONE3_ARGS_NO_TEST);
137
138	/* Do a clone3() in a new PID NS.*/
139	if (uid == 0)
140		test_clone3(CLONE_NEWPID, 0, 0, CLONE3_ARGS_NO_TEST);
141	else
142		ksft_test_result_skip("Skipping clone3() with CLONE_NEWPID\n");
143
144	/* Do a clone3() with CLONE_ARGS_SIZE_VER0. */
145	test_clone3(0, CLONE_ARGS_SIZE_VER0, 0, CLONE3_ARGS_NO_TEST);
146
147	/* Do a clone3() with CLONE_ARGS_SIZE_VER0 - 8 */
148	test_clone3(0, CLONE_ARGS_SIZE_VER0 - 8, -EINVAL, CLONE3_ARGS_NO_TEST);
149
150	/* Do a clone3() with sizeof(struct clone_args) + 8 */
151	test_clone3(0, sizeof(struct __clone_args) + 8, 0, CLONE3_ARGS_NO_TEST);
152
153	/* Do a clone3() with exit_signal having highest 32 bits non-zero */
154	test_clone3(0, 0, -EINVAL, CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG);
155
156	/* Do a clone3() with negative 32-bit exit_signal */
157	test_clone3(0, 0, -EINVAL, CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG);
158
159	/* Do a clone3() with exit_signal not fitting into CSIGNAL mask */
160	test_clone3(0, 0, -EINVAL, CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG);
161
162	/* Do a clone3() with NSIG < exit_signal < CSIG */
163	test_clone3(0, 0, -EINVAL, CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG);
164
165	test_clone3(0, sizeof(struct __clone_args) + 8, 0, CLONE3_ARGS_ALL_0);
166
167	test_clone3(0, sizeof(struct __clone_args) + 16, -E2BIG,
168			CLONE3_ARGS_ALL_0);
169
170	test_clone3(0, sizeof(struct __clone_args) * 2, -E2BIG,
171			CLONE3_ARGS_ALL_0);
172
173	/* Do a clone3() with > page size */
174	test_clone3(0, getpagesize() + 8, -E2BIG, CLONE3_ARGS_NO_TEST);
175
176	/* Do a clone3() with CLONE_ARGS_SIZE_VER0 in a new PID NS. */
177	if (uid == 0)
178		test_clone3(CLONE_NEWPID, CLONE_ARGS_SIZE_VER0, 0,
179				CLONE3_ARGS_NO_TEST);
180	else
181		ksft_test_result_skip("Skipping clone3() with CLONE_NEWPID\n");
182
183	/* Do a clone3() with CLONE_ARGS_SIZE_VER0 - 8 in a new PID NS */
184	test_clone3(CLONE_NEWPID, CLONE_ARGS_SIZE_VER0 - 8, -EINVAL,
185			CLONE3_ARGS_NO_TEST);
186
187	/* Do a clone3() with sizeof(struct clone_args) + 8 in a new PID NS */
188	if (uid == 0)
189		test_clone3(CLONE_NEWPID, sizeof(struct __clone_args) + 8, 0,
190				CLONE3_ARGS_NO_TEST);
191	else
192		ksft_test_result_skip("Skipping clone3() with CLONE_NEWPID\n");
193
194	/* Do a clone3() with > page size in a new PID NS */
195	test_clone3(CLONE_NEWPID, getpagesize() + 8, -E2BIG,
196			CLONE3_ARGS_NO_TEST);
197
198	return !ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();
199}
200