1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #ifndef _CLONE3_SELFTESTS_H
4 #define _CLONE3_SELFTESTS_H
5 
6 #define _GNU_SOURCE
7 #include <sched.h>
8 #include <linux/sched.h>
9 #include <linux/types.h>
10 #include <stdint.h>
11 #include <syscall.h>
12 #include <sys/wait.h>
13 
14 #include "../kselftest.h"
15 
16 #define ptr_to_u64(ptr) ((__u64)((uintptr_t)(ptr)))
17 
18 #ifndef CLONE_INTO_CGROUP
19 #define CLONE_INTO_CGROUP 0x200000000ULL /* Clone into a specific cgroup given the right permissions. */
20 #endif
21 
22 #ifndef __NR_clone3
23 #define __NR_clone3 -1
24 #endif
25 
26 struct __clone_args {
27 	__aligned_u64 flags;
28 	__aligned_u64 pidfd;
29 	__aligned_u64 child_tid;
30 	__aligned_u64 parent_tid;
31 	__aligned_u64 exit_signal;
32 	__aligned_u64 stack;
33 	__aligned_u64 stack_size;
34 	__aligned_u64 tls;
35 #ifndef CLONE_ARGS_SIZE_VER0
36 #define CLONE_ARGS_SIZE_VER0 64	/* sizeof first published struct */
37 #endif
38 	__aligned_u64 set_tid;
39 	__aligned_u64 set_tid_size;
40 #ifndef CLONE_ARGS_SIZE_VER1
41 #define CLONE_ARGS_SIZE_VER1 80	/* sizeof second published struct */
42 #endif
43 	__aligned_u64 cgroup;
44 #ifndef CLONE_ARGS_SIZE_VER2
45 #define CLONE_ARGS_SIZE_VER2 88	/* sizeof third published struct */
46 #endif
47 };
48 
49 static pid_t sys_clone3(struct __clone_args *args, size_t size)
50 {
51 	fflush(stdout);
52 	fflush(stderr);
53 	return syscall(__NR_clone3, args, size);
54 }
55 
56 static inline void test_clone3_supported(void)
57 {
58 	pid_t pid;
59 	struct __clone_args args = {};
60 
61 	if (__NR_clone3 < 0)
62 		ksft_exit_skip("clone3() syscall is not supported\n");
63 
64 	/* Set to something that will always cause EINVAL. */
65 	args.exit_signal = -1;
66 	pid = sys_clone3(&args, sizeof(args));
67 	if (!pid)
68 		exit(EXIT_SUCCESS);
69 
70 	if (pid > 0) {
71 		wait(NULL);
72 		ksft_exit_fail_msg(
73 			"Managed to create child process with invalid exit_signal\n");
74 	}
75 
76 	if (errno == ENOSYS)
77 		ksft_exit_skip("clone3() syscall is not supported\n");
78 
79 	ksft_print_msg("clone3() syscall supported\n");
80 }
81 
82 #endif /* _CLONE3_SELFTESTS_H */
83