// SPDX-License-Identifier: GPL-2.0 /* Based on Christian Brauner's clone3() example */ #define _GNU_SOURCE#include <errno.h>#include <inttypes.h>#include <linux/types.h>#include <linux/sched.h>#include <stdbool.h>#include <stdint.h>#include <stdio.h>#include <stdlib.h>#include <sys/syscall.h>#include <sys/types.h>#include <sys/un.h>#include <sys/wait.h>#include <unistd.h>#include <sched.h> #include "kselftest.h"#include "clone3_selftests.h" enum test_mode {	CLONE3_ARGS_NO_TEST,	CLONE3_ARGS_ALL_0,	CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG,	CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG,	CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG,	CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG,}; static int call_clone3(uint64_t flags, size_t size, enum test_mode test_mode){	struct __clone_args args = {		.flags = flags,		.exit_signal = SIGCHLD,	}; 	struct clone_args_extended {		struct __clone_args args;		__aligned_u64 excess_space[2];	} args_ext; 	pid_t pid = -1;	int status; 	memset(&args_ext, 0, sizeof(args_ext));	if (size > sizeof(struct __clone_args))		args_ext.excess_space[1] = 1; 	if (size == 0)		size = sizeof(struct __clone_args); 	switch (test_mode) {	case CLONE3_ARGS_NO_TEST:		/*		 * Uses default 'flags' and 'SIGCHLD'		 * assignment.		 */		break;	case CLONE3_ARGS_ALL_0:		args.flags = 0;		args.exit_signal = 0;		break;	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG:		args.exit_signal = 0xbadc0ded00000000ULL;		break;	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG:		args.exit_signal = 0x0000000080000000ULL;		break;	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG:		args.exit_signal = 0x0000000000000100ULL;		break;	case CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG:		args.exit_signal = 0x00000000000000f0ULL;		break;	} 	memcpy(&args_ext.args, &args, sizeof(struct __clone_args)); 	pid = sys_clone3((struct __clone_args *)&args_ext, size);	if (pid < 0) {		ksft_print_msg("%s - Failed to create new process\n",				strerror(errno));		return -errno;	} 	if (pid == 0) {		ksft_print_msg("I am the child, my PID is %d\n", getpid());		_exit(EXIT_SUCCESS);	} 	ksft_print_msg("I am the parent (%d). My child's pid is %d\n",			getpid(), pid); 	if (waitpid(-1, &status, __WALL) < 0) {		ksft_print_msg("waitpid() returned %s\n", strerror(errno));		return -errno;	}	if (!WIFEXITED(status)) {		ksft_print_msg("Child did not exit normally, status 0x%x\n",			       status);		return EXIT_FAILURE;	}	if (WEXITSTATUS(status))		return WEXITSTATUS(status); 	return 0;} static bool test_clone3(uint64_t flags, size_t size, int expected,			enum test_mode test_mode){	int ret; 	ksft_print_msg(		"[%d] Trying clone3() with flags %#" PRIx64 " (size %zu)\n",		getpid(), flags, size);	ret = call_clone3(flags, size, test_mode);	ksft_print_msg("[%d] clone3() with flags says: %d expected %d\n",			getpid(), ret, expected);	if (ret != expected) {		ksft_print_msg(			"[%d] Result (%d) is different than expected (%d)\n",			getpid(), ret, expected);		return false;	} 	return true;} typedef bool (*filter_function)(void);typedef size_t (*size_function)(void); static bool not_root(void){	if (getuid() != 0) {		ksft_print_msg("Not running as root\n");		return true;	} 	return false;} static bool no_timenamespace(void){	if (not_root())		return true; 	if (!access("/proc/self/ns/time", F_OK))		return false; 	ksft_print_msg("Time namespaces are not supported\n");	return true;} static size_t page_size_plus_8(void){	return getpagesize() + 8;} struct test {	const char *name;	uint64_t flags;	size_t size;	size_function size_function;	int expected;	enum test_mode test_mode;	filter_function filter;}; static const struct test tests[] = {	{		.name = "simple clone3()",		.flags = 0,		.size = 0,		.expected = 0,		.test_mode = CLONE3_ARGS_NO_TEST,	},	{		.name = "clone3() in a new PID_NS",		.flags = CLONE_NEWPID,		.size = 0,		.expected = 0,		.test_mode = CLONE3_ARGS_NO_TEST,		.filter = not_root,	},	{		.name = "CLONE_ARGS_SIZE_VER0",		.flags = 0,		.size = CLONE_ARGS_SIZE_VER0,		.expected = 0,		.test_mode = CLONE3_ARGS_NO_TEST,	},	{		.name = "CLONE_ARGS_SIZE_VER0 - 8",		.flags = 0,		.size = CLONE_ARGS_SIZE_VER0 - 8,		.expected = -EINVAL,		.test_mode = CLONE3_ARGS_NO_TEST,	},	{		.name = "sizeof(struct clone_args) + 8",		.flags = 0,		.size = sizeof(struct __clone_args) + 8,		.expected = 0,		.test_mode = CLONE3_ARGS_NO_TEST,	},	{		.name = "exit_signal with highest 32 bits non-zero",		.flags = 0,		.size = 0,		.expected = -EINVAL,		.test_mode = CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG,	},	{		.name = "negative 32-bit exit_signal",		.flags = 0,		.size = 0,		.expected = -EINVAL,		.test_mode = CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG,	},	{		.name = "exit_signal not fitting into CSIGNAL mask",		.flags = 0,		.size = 0,		.expected = -EINVAL,		.test_mode = CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG,	},	{		.name = "NSIG < exit_signal < CSIG",		.flags = 0,		.size = 0,		.expected = -EINVAL,		.test_mode = CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG,	},	{		.name = "Arguments sizeof(struct clone_args) + 8",		.flags = 0,		.size = sizeof(struct __clone_args) + 8,		.expected = 0,		.test_mode = CLONE3_ARGS_ALL_0,	},	{		.name = "Arguments sizeof(struct clone_args) + 16",		.flags = 0,		.size = sizeof(struct __clone_args) + 16,		.expected = -E2BIG,		.test_mode = CLONE3_ARGS_ALL_0,	},	{		.name = "Arguments sizeof(struct clone_arg) * 2",		.flags = 0,		.size = sizeof(struct __clone_args) + 16,		.expected = -E2BIG,		.test_mode = CLONE3_ARGS_ALL_0,	},	{		.name = "Arguments > page size",		.flags = 0,		.size_function = page_size_plus_8,		.expected = -E2BIG,		.test_mode = CLONE3_ARGS_NO_TEST,	},	{		.name = "CLONE_ARGS_SIZE_VER0 in a new PID NS",		.flags = CLONE_NEWPID,		.size = CLONE_ARGS_SIZE_VER0,		.expected = 0,		.test_mode = CLONE3_ARGS_NO_TEST,		.filter = not_root,	},	{		.name = "CLONE_ARGS_SIZE_VER0 - 8 in a new PID NS",		.flags = CLONE_NEWPID,		.size = CLONE_ARGS_SIZE_VER0 - 8,		.expected = -EINVAL,		.test_mode = CLONE3_ARGS_NO_TEST,	},	{		.name = "sizeof(struct clone_args) + 8 in a new PID NS",		.flags = CLONE_NEWPID,		.size = sizeof(struct __clone_args) + 8,		.expected = 0,		.test_mode = CLONE3_ARGS_NO_TEST,		.filter = not_root,	},	{		.name = "Arguments > page size in a new PID NS",		.flags = CLONE_NEWPID,		.size_function = page_size_plus_8,		.expected = -E2BIG,		.test_mode = CLONE3_ARGS_NO_TEST,	},	{		.name = "New time NS",		.flags = CLONE_NEWTIME,		.size = 0,		.expected = 0,		.test_mode = CLONE3_ARGS_NO_TEST,		.filter = no_timenamespace,	},	{		.name = "exit signal (SIGCHLD) in flags",		.flags = SIGCHLD,		.size = 0,		.expected = -EINVAL,		.test_mode = CLONE3_ARGS_NO_TEST,	},}; int main(int argc, char *argv[]){	size_t size;	int i; 	ksft_print_header();	ksft_set_plan(ARRAY_SIZE(tests));	test_clone3_supported(); 	for (i = 0; i < ARRAY_SIZE(tests); i++) {		if (tests[i].filter && tests[i].filter()) {			ksft_test_result_skip("%s\n", tests[i].name);			continue;		} 		if (tests[i].size_function)			size = tests[i].size_function();		else			size = tests[i].size; 		ksft_print_msg("Running test '%s'\n", tests[i].name); 		ksft_test_result(test_clone3(tests[i].flags, size,					     tests[i].expected,					     tests[i].test_mode),				 "%s\n", tests[i].name);	} 	ksft_finished();}