1 /*
2 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
5
6 #include <signal.h>
7 #include <sched.h>
8 #include <asm/unistd.h>
9 #include <sys/time.h>
10 #include "as-layout.h"
11 #include "ptrace_user.h"
12 #include "stub-data.h"
13 #include "sysdep/stub.h"
14
15 /*
16 * This is in a separate file because it needs to be compiled with any
17 * extraneous gcc flags (-pg, -fprofile-arcs, -ftest-coverage) disabled
18 *
19 * Use UM_KERN_PAGE_SIZE instead of PAGE_SIZE because that calls getpagesize
20 * on some systems.
21 */
22
23 void __attribute__ ((__section__ (".__syscall_stub")))
stub_clone_handler(void)24 stub_clone_handler(void)
25 {
26 struct stub_data *data = (struct stub_data *) STUB_DATA;
27 long err;
28
29 err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD,
30 STUB_DATA + UM_KERN_PAGE_SIZE / 2 - sizeof(void *));
31 if (err != 0)
32 goto out;
33
34 err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0);
35 if (err)
36 goto out;
37
38 err = stub_syscall3(__NR_setitimer, ITIMER_VIRTUAL,
39 (long) &data->timer, 0);
40 if (err)
41 goto out;
42
43 remap_stack(data->fd, data->offset);
44 goto done;
45
46 out:
47 /*
48 * save current result.
49 * Parent: pid;
50 * child: retcode of mmap already saved and it jumps around this
51 * assignment
52 */
53 data->err = err;
54 done:
55 trap_myself();
56 }
57