@@ -12833,6 +12833,7 @@ S: Maintained
T: git git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux.git
F: samples/pidfd/
F: tools/testing/selftests/pidfd/
+F: tools/testing/selftests/clone3/
K: (?i)pidfd
K: (?i)clone3
K: \b(clone_args|kernel_clone_args)\b
@@ -4,6 +4,7 @@ TARGETS += bpf
TARGETS += breakpoints
TARGETS += capabilities
TARGETS += cgroup
+TARGETS += clone3
TARGETS += cpufreq
TARGETS += cpu-hotplug
TARGETS += drivers/dma-buf
new file mode 100644
@@ -0,0 +1 @@
+clone3
new file mode 100644
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+CFLAGS += -I../../../../usr/include/
+
+TEST_GEN_PROGS := clone3
+
+include ../lib.mk
new file mode 100644
@@ -0,0 +1,205 @@
+// 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 <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"
+
+/*
+ * Different sizes of struct clone_args
+ */
+#ifndef CLONE3_ARGS_SIZE_V0
+#define CLONE3_ARGS_SIZE_V0 64
+#endif
+
+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 pid_t raw_clone(struct clone_args *args, size_t size)
+{
+ return syscall(__NR_clone3, args, size);
+}
+
+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_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 = raw_clone((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("Child returned %s\n", strerror(errno));
+ return -errno;
+ }
+ if (WEXITSTATUS(status))
+ return WEXITSTATUS(status);
+
+ return 0;
+}
+
+static void 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_test_result_fail(
+ "[%d] Result (%d) is different than expected (%d)\n",
+ getpid(), ret, expected);
+ else
+ ksft_test_result_pass(
+ "[%d] Result (%d) matches expectation (%d)\n",
+ getpid(), ret, expected);
+}
+
+int main(int argc, char *argv[])
+{
+ pid_t pid;
+
+ uid_t uid = getuid();
+
+ ksft_print_header();
+ ksft_set_plan(17);
+
+ /* Just a simple clone3() should return 0.*/
+ test_clone3(0, 0, 0, CLONE3_ARGS_NO_TEST);
+
+ /* Do a clone3() in a new PID NS.*/
+ if (uid == 0)
+ test_clone3(CLONE_NEWPID, 0, 0, CLONE3_ARGS_NO_TEST);
+ else
+ ksft_test_result_skip("Skipping clone3() with CLONE_NEWPID\n");
+
+ /* Do a clone3() with CLONE3_ARGS_SIZE_V0. */
+ test_clone3(0, CLONE3_ARGS_SIZE_V0, 0, CLONE3_ARGS_NO_TEST);
+
+ /* Do a clone3() with CLONE3_ARGS_SIZE_V0 - 8 */
+ test_clone3(0, CLONE3_ARGS_SIZE_V0 - 8, -EINVAL, CLONE3_ARGS_NO_TEST);
+
+ /* Do a clone3() with sizeof(struct clone_args) + 8 */
+ test_clone3(0, sizeof(struct clone_args) + 8, 0, CLONE3_ARGS_NO_TEST);
+
+ /* Do a clone3() with exit_signal having highest 32 bits non-zero */
+ test_clone3(0, 0, -EINVAL, CLONE3_ARGS_INVAL_EXIT_SIGNAL_BIG);
+
+ /* Do a clone3() with negative 32-bit exit_signal */
+ test_clone3(0, 0, -EINVAL, CLONE3_ARGS_INVAL_EXIT_SIGNAL_NEG);
+
+ /* Do a clone3() with exit_signal not fitting into CSIGNAL mask */
+ test_clone3(0, 0, -EINVAL, CLONE3_ARGS_INVAL_EXIT_SIGNAL_CSIG);
+
+ /* Do a clone3() with NSIG < exit_signal < CSIG */
+ test_clone3(0, 0, -EINVAL, CLONE3_ARGS_INVAL_EXIT_SIGNAL_NSIG);
+
+ test_clone3(0, sizeof(struct clone_args) + 8, 0, CLONE3_ARGS_ALL_0);
+
+ test_clone3(0, sizeof(struct clone_args) + 16, -E2BIG,
+ CLONE3_ARGS_ALL_0);
+
+ test_clone3(0, sizeof(struct clone_args) * 2, -E2BIG,
+ CLONE3_ARGS_ALL_0);
+
+ /* Do a clone3() with > page size */
+ test_clone3(0, getpagesize() + 8, -E2BIG, CLONE3_ARGS_NO_TEST);
+
+ /* Do a clone3() with CLONE3_ARGS_SIZE_V0 in a new PID NS. */
+ if (uid == 0)
+ test_clone3(CLONE_NEWPID, CLONE3_ARGS_SIZE_V0, 0,
+ CLONE3_ARGS_NO_TEST);
+ else
+ ksft_test_result_skip("Skipping clone3() with CLONE_NEWPID\n");
+
+ /* Do a clone3() with CLONE3_ARGS_SIZE_V0 - 8 in a new PID NS */
+ test_clone3(CLONE_NEWPID, CLONE3_ARGS_SIZE_V0 - 8, -EINVAL,
+ CLONE3_ARGS_NO_TEST);
+
+ /* Do a clone3() with sizeof(struct clone_args) + 8 in a new PID NS */
+ if (uid == 0)
+ test_clone3(CLONE_NEWPID, sizeof(struct clone_args) + 8, 0,
+ CLONE3_ARGS_NO_TEST);
+ else
+ ksft_test_result_skip("Skipping clone3() with CLONE_NEWPID\n");
+
+ /* Do a clone3() with > page size in a new PID NS */
+ test_clone3(CLONE_NEWPID, getpagesize() + 8, -E2BIG,
+ CLONE3_ARGS_NO_TEST);
+
+ return !ksft_get_fail_cnt() ? ksft_exit_pass() : ksft_exit_fail();
+}