1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
|
/*
* Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#ifndef __UM_UACCESS_H
#define __UM_UACCESS_H
/* thread_info has a mm_segment_t in it, so put the definition up here */
typedef struct {
unsigned long seg;
} mm_segment_t;
#include <linux/thread_info.h>
#include <linux/errno.h>
#include <asm/processor.h>
#include <asm/elf.h>
#define VERIFY_READ 0
#define VERIFY_WRITE 1
/*
* The fs value determines whether argument validity checking should be
* performed or not. If get_fs() == USER_DS, checking is performed, with
* get_fs() == KERNEL_DS, checking is bypassed.
*
* For historical reasons, these macros are grossly misnamed.
*/
#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF)
#define USER_DS MAKE_MM_SEG(TASK_SIZE)
#define get_ds() (KERNEL_DS)
#define get_fs() (current_thread_info()->addr_limit)
#define set_fs(x) (current_thread_info()->addr_limit = (x))
#define segment_eq(a, b) ((a).seg == (b).seg)
#define __under_task_size(addr, size) \
(((unsigned long) (addr) < TASK_SIZE) && \
(((unsigned long) (addr) + (size)) < TASK_SIZE))
#define __access_ok_vsyscall(type, addr, size) \
((type == VERIFY_READ) && \
((unsigned long) (addr) >= FIXADDR_USER_START) && \
((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \
((unsigned long) (addr) + (size) >= (unsigned long)(addr)))
#define __addr_range_nowrap(addr, size) \
((unsigned long) (addr) <= ((unsigned long) (addr) + (size)))
#define access_ok(type, addr, size) \
(__addr_range_nowrap(addr, size) && \
(__under_task_size(addr, size) || \
__access_ok_vsyscall(type, addr, size) || \
segment_eq(get_fs(), KERNEL_DS)))
extern int copy_from_user(void *to, const void __user *from, int n);
extern int copy_to_user(void __user *to, const void *from, int n);
/*
* strncpy_from_user: - Copy a NUL terminated string from userspace.
* @dst: Destination address, in kernel space. This buffer must be at
* least @count bytes long.
* @src: Source address, in user space.
* @count: Maximum number of bytes to copy, including the trailing NUL.
*
* Copies a NUL-terminated string from userspace to kernel space.
*
* On success, returns the length of the string (not including the trailing
* NUL).
*
* If access to userspace fails, returns -EFAULT (some data may have been
* copied).
*
* If @count is smaller than the length of the string, copies @count bytes
* and returns @count.
*/
extern int strncpy_from_user(char *dst, const char __user *src, int count);
/*
* __clear_user: - Zero a block of memory in user space, with less checking.
* @to: Destination address, in user space.
* @n: Number of bytes to zero.
*
* Zero a block of memory in user space. Caller must check
* the specified block with access_ok() before calling this function.
*
* Returns number of bytes that could not be cleared.
* On success, this will be zero.
*/
extern int __clear_user(void __user *mem, int len);
/*
* clear_user: - Zero a block of memory in user space.
* @to: Destination address, in user space.
* @n: Number of bytes to zero.
*
* Zero a block of memory in user space.
*
* Returns number of bytes that could not be cleared.
* On success, this will be zero.
*/
extern int clear_user(void __user *mem, int len);
/*
* strlen_user: - Get the size of a string in user space.
* @str: The string to measure.
* @n: The maximum valid length
*
* Get the size of a NUL-terminated string in user space.
*
* Returns the size of the string INCLUDING the terminating NUL.
* On exception, returns 0.
* If the string is too long, returns a value greater than @n.
*/
extern int strnlen_user(const void __user *str, int len);
#define __copy_from_user(to, from, n) copy_from_user(to, from, n)
#define __copy_to_user(to, from, n) copy_to_user(to, from, n)
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
#define __get_user(x, ptr) \
({ \
const __typeof__(*(ptr)) __user *__private_ptr = (ptr); \
__typeof__(x) __private_val; \
int __private_ret = -EFAULT; \
(x) = (__typeof__(*(__private_ptr)))0; \
if (__copy_from_user((__force void *)&__private_val, (__private_ptr),\
sizeof(*(__private_ptr))) == 0) { \
(x) = (__typeof__(*(__private_ptr))) __private_val; \
__private_ret = 0; \
} \
__private_ret; \
})
#define get_user(x, ptr) \
({ \
const __typeof__((*(ptr))) __user *private_ptr = (ptr); \
(access_ok(VERIFY_READ, private_ptr, sizeof(*private_ptr)) ? \
__get_user(x, private_ptr) : ((x) = (__typeof__(*ptr))0, -EFAULT)); \
})
#define __put_user(x, ptr) \
({ \
__typeof__(*(ptr)) __user *__private_ptr = ptr; \
__typeof__(*(__private_ptr)) __private_val; \
int __private_ret = -EFAULT; \
__private_val = (__typeof__(*(__private_ptr))) (x); \
if (__copy_to_user((__private_ptr), &__private_val, \
sizeof(*(__private_ptr))) == 0) { \
__private_ret = 0; \
} \
__private_ret; \
})
#define put_user(x, ptr) \
({ \
__typeof__(*(ptr)) __user *private_ptr = (ptr); \
(access_ok(VERIFY_WRITE, private_ptr, sizeof(*private_ptr)) ? \
__put_user(x, private_ptr) : -EFAULT); \
})
#define strlen_user(str) strnlen_user(str, ~0U >> 1)
struct exception_table_entry
{
unsigned long insn;
unsigned long fixup;
};
#endif
|
