/arch/um/sys-i386/ldt.c

 1/*
 2 * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
 3 * Licensed under the GPL
 4 */
 5
 6#include "linux/config.h"
 7#include "linux/slab.h"
 8#include "asm/uaccess.h"
 9#include "asm/ptrace.h"
10#include "choose-mode.h"
11#include "kern.h"
12
13#ifdef CONFIG_MODE_TT
14extern int modify_ldt(int func, void *ptr, unsigned long bytecount);
15
16/* XXX this needs copy_to_user and copy_from_user */
17
18int sys_modify_ldt_tt(int func, void __user *ptr, unsigned long bytecount)
19{
20	if (!access_ok(VERIFY_READ, ptr, bytecount))
21		return -EFAULT;
22
23	return modify_ldt(func, ptr, bytecount);
24}
25#endif
26
27#ifdef CONFIG_MODE_SKAS
28extern int userspace_pid;
29
30#include "skas_ptrace.h"
31
32int sys_modify_ldt_skas(int func, void __user *ptr, unsigned long bytecount)
33{
34	struct ptrace_ldt ldt;
35	void *buf;
36	int res, n;
37
38	buf = kmalloc(bytecount, GFP_KERNEL);
39	if(buf == NULL)
40		return(-ENOMEM);
41
42	res = 0;
43
44	switch(func){
45	case 1:
46	case 0x11:
47		res = copy_from_user(buf, ptr, bytecount);
48		break;
49	}
50
51	if(res != 0){
52		res = -EFAULT;
53		goto out;
54	}
55
56	ldt = ((struct ptrace_ldt) { .func	= func,
57				     .ptr	= buf,
58				     .bytecount = bytecount });
59	res = ptrace(PTRACE_LDT, userspace_pid, 0, (unsigned long) &ldt);
60	if(res < 0)
61		goto out;
62
63	switch(func){
64	case 0:
65	case 2:
66		n = res;
67		res = copy_to_user(ptr, buf, n);
68		if(res != 0)
69			res = -EFAULT;
70		else 
71			res = n;
72		break;
73	}
74
75 out:
76	kfree(buf);
77	return(res);
78}
79#endif
80
81int sys_modify_ldt(int func, void __user *ptr, unsigned long bytecount)
82{
83	return(CHOOSE_MODE_PROC(sys_modify_ldt_tt, sys_modify_ldt_skas, func, 
84				ptr, bytecount));
85}
86
87
88
89/*
90 * Overrides for Emacs so that we follow Linus's tabbing style.
91 * Emacs will notice this stuff at the end of the file and automatically
92 * adjust the settings for this buffer only.  This must remain at the end
93 * of the file.
94 * ---------------------------------------------------------------------------
95 * Local variables:
96 * c-file-style: "linux"
97 * End:
98 */