clone3.c (5382B)
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}