1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
4 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
5 */
6
7#include <signal.h>
8#include <sched.h>
9#include <asm/unistd.h>
10#include <sys/time.h>
11#include <as-layout.h>
12#include <ptrace_user.h>
13#include <stub-data.h>
14#include <sysdep/stub.h>
15
16/*
17 * This is in a separate file because it needs to be compiled with any
18 * extraneous gcc flags (-pg, -fprofile-arcs, -ftest-coverage) disabled
19 *
20 * Use UM_KERN_PAGE_SIZE instead of PAGE_SIZE because that calls getpagesize
21 * on some systems.
22 */
23
24void __attribute__ ((__section__ (".__syscall_stub")))
25stub_clone_handler(void)
26{
27	struct stub_data *data = get_stub_data();
28	long err;
29
30	err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD,
31			    (unsigned long)data +
32				STUB_DATA_PAGES * UM_KERN_PAGE_SIZE / 2);
33	if (err) {
34		data->parent_err = err;
35		goto done;
36	}
37
38	err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0);
39	if (err) {
40		data->child_err = err;
41		goto done;
42	}
43
44	remap_stack_and_trap();
45
46 done:
47	trap_myself();
48}
49