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
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* __put_user functions.
*
* (C) Copyright 2005 Linus Torvalds
* (C) Copyright 2005 Andi Kleen
* (C) Copyright 2008 Glauber Costa
*
* These functions have a non-standard call interface
* to make them more efficient, especially as they
* return an error value in addition to the "real"
* return value.
*/
#include <linux/linkage.h>
#include <asm/thread_info.h>
#include <asm/errno.h>
#include <asm/asm.h>
#include <asm/smap.h>
#include <asm/export.h>
/*
* __put_user_X
*
* Inputs: %eax[:%edx] contains the data
* %ecx contains the address
*
* Outputs: %ecx is error code (0 or -EFAULT)
*
* Clobbers: %ebx needed for task pointer
*
* These functions should not modify any other registers,
* as they get called from within inline assembly.
*/
.macro check_range size:req
.if IS_ENABLED(CONFIG_X86_64)
mov %rcx, %rbx
sar $63, %rbx
or %rbx, %rcx
.else
cmp $TASK_SIZE_MAX-\size+1, %ecx
jae .Lbad_put_user
.endif
.endm
.text
SYM_FUNC_START(__put_user_1)
check_range size=1
ASM_STAC
1: movb %al,(%_ASM_CX)
xor %ecx,%ecx
ASM_CLAC
RET
SYM_FUNC_END(__put_user_1)
EXPORT_SYMBOL(__put_user_1)
SYM_FUNC_START(__put_user_nocheck_1)
ASM_STAC
2: movb %al,(%_ASM_CX)
xor %ecx,%ecx
ASM_CLAC
RET
SYM_FUNC_END(__put_user_nocheck_1)
EXPORT_SYMBOL(__put_user_nocheck_1)
SYM_FUNC_START(__put_user_2)
check_range size=2
ASM_STAC
3: movw %ax,(%_ASM_CX)
xor %ecx,%ecx
ASM_CLAC
RET
SYM_FUNC_END(__put_user_2)
EXPORT_SYMBOL(__put_user_2)
SYM_FUNC_START(__put_user_nocheck_2)
ASM_STAC
4: movw %ax,(%_ASM_CX)
xor %ecx,%ecx
ASM_CLAC
RET
SYM_FUNC_END(__put_user_nocheck_2)
EXPORT_SYMBOL(__put_user_nocheck_2)
SYM_FUNC_START(__put_user_4)
check_range size=4
ASM_STAC
5: movl %eax,(%_ASM_CX)
xor %ecx,%ecx
ASM_CLAC
RET
SYM_FUNC_END(__put_user_4)
EXPORT_SYMBOL(__put_user_4)
SYM_FUNC_START(__put_user_nocheck_4)
ASM_STAC
6: movl %eax,(%_ASM_CX)
xor %ecx,%ecx
ASM_CLAC
RET
SYM_FUNC_END(__put_user_nocheck_4)
EXPORT_SYMBOL(__put_user_nocheck_4)
SYM_FUNC_START(__put_user_8)
check_range size=8
ASM_STAC
7: mov %_ASM_AX,(%_ASM_CX)
#ifdef CONFIG_X86_32
8: movl %edx,4(%_ASM_CX)
#endif
xor %ecx,%ecx
ASM_CLAC
RET
SYM_FUNC_END(__put_user_8)
EXPORT_SYMBOL(__put_user_8)
SYM_FUNC_START(__put_user_nocheck_8)
ASM_STAC
9: mov %_ASM_AX,(%_ASM_CX)
#ifdef CONFIG_X86_32
10: movl %edx,4(%_ASM_CX)
#endif
xor %ecx,%ecx
ASM_CLAC
RET
SYM_FUNC_END(__put_user_nocheck_8)
EXPORT_SYMBOL(__put_user_nocheck_8)
SYM_CODE_START_LOCAL(__put_user_handle_exception)
ASM_CLAC
.Lbad_put_user:
movl $-EFAULT,%ecx
RET
SYM_CODE_END(__put_user_handle_exception)
_ASM_EXTABLE(1b, __put_user_handle_exception)
_ASM_EXTABLE(2b, __put_user_handle_exception)
_ASM_EXTABLE(3b, __put_user_handle_exception)
_ASM_EXTABLE(4b, __put_user_handle_exception)
_ASM_EXTABLE(5b, __put_user_handle_exception)
_ASM_EXTABLE(6b, __put_user_handle_exception)
_ASM_EXTABLE(7b, __put_user_handle_exception)
_ASM_EXTABLE(9b, __put_user_handle_exception)
#ifdef CONFIG_X86_32
_ASM_EXTABLE(8b, __put_user_handle_exception)
_ASM_EXTABLE(10b, __put_user_handle_exception)
#endif
|
