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
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
|
/*
* Access to user system call parameters and results
*
* Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License v.2.
*
* See asm-generic/syscall.h for descriptions of what we must do here.
*/
#ifndef _ASM_X86_SYSCALL_H
#define _ASM_X86_SYSCALL_H
#include <linux/audit.h>
#include <linux/sched.h>
#include <linux/err.h>
#include <asm/asm-offsets.h> /* For NR_syscalls */
#include <asm/thread_info.h> /* for TS_COMPAT */
#include <asm/unistd.h>
typedef void (*sys_call_ptr_t)(void);
extern const sys_call_ptr_t sys_call_table[];
/*
* Only the low 32 bits of orig_ax are meaningful, so we return int.
* This importantly ignores the high bits on 64-bit, so comparisons
* sign-extend the low 32 bits.
*/
static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
{
return regs->orig_ax;
}
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
regs->ax = regs->orig_ax;
}
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
unsigned long error = regs->ax;
#ifdef CONFIG_IA32_EMULATION
/*
* TS_COMPAT is set for 32-bit syscall entries and then
* remains set until we return to user mode.
*/
if (task_thread_info(task)->status & TS_COMPAT)
/*
* Sign-extend the value so (int)-EFOO becomes (long)-EFOO
* and will match correctly in comparisons.
*/
error = (long) (int) error;
#endif
return IS_ERR_VALUE(error) ? error : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
return regs->ax;
}
static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
regs->ax = (long) error ?: val;
}
#ifdef CONFIG_X86_32
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
unsigned long *args)
{
BUG_ON(i + n > 6);
memcpy(args, ®s->bx + i, n * sizeof(args[0]));
}
static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
const unsigned long *args)
{
BUG_ON(i + n > 6);
memcpy(®s->bx + i, args, n * sizeof(args[0]));
}
static inline int syscall_get_arch(struct task_struct *task,
struct pt_regs *regs)
{
return AUDIT_ARCH_I386;
}
#else /* CONFIG_X86_64 */
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
unsigned long *args)
{
# ifdef CONFIG_IA32_EMULATION
if (task_thread_info(task)->status & TS_COMPAT)
switch (i) {
case 0:
if (!n--) break;
*args++ = regs->bx;
case 1:
if (!n--) break;
*args++ = regs->cx;
case 2:
if (!n--) break;
*args++ = regs->dx;
case 3:
if (!n--) break;
*args++ = regs->si;
case 4:
if (!n--) break;
*args++ = regs->di;
case 5:
if (!n--) break;
*args++ = regs->bp;
case 6:
if (!n--) break;
default:
BUG();
break;
}
else
# endif
switch (i) {
case 0:
if (!n--) break;
*args++ = regs->di;
case 1:
if (!n--) break;
*args++ = regs->si;
case 2:
if (!n--) break;
*args++ = regs->dx;
case 3:
if (!n--) break;
*args++ = regs->r10;
case 4:
if (!n--) break;
*args++ = regs->r8;
case 5:
if (!n--) break;
*args++ = regs->r9;
case 6:
if (!n--) break;
default:
BUG();
break;
}
}
static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
const unsigned long *args)
{
# ifdef CONFIG_IA32_EMULATION
if (task_thread_info(task)->status & TS_COMPAT)
switch (i) {
case 0:
if (!n--) break;
regs->bx = *args++;
case 1:
if (!n--) break;
regs->cx = *args++;
case 2:
if (!n--) break;
regs->dx = *args++;
case 3:
if (!n--) break;
regs->si = *args++;
case 4:
if (!n--) break;
regs->di = *args++;
case 5:
if (!n--) break;
regs->bp = *args++;
case 6:
if (!n--) break;
default:
BUG();
break;
}
else
# endif
switch (i) {
case 0:
if (!n--) break;
regs->di = *args++;
case 1:
if (!n--) break;
regs->si = *args++;
case 2:
if (!n--) break;
regs->dx = *args++;
case 3:
if (!n--) break;
regs->r10 = *args++;
case 4:
if (!n--) break;
regs->r8 = *args++;
case 5:
if (!n--) break;
regs->r9 = *args++;
case 6:
if (!n--) break;
default:
BUG();
break;
}
}
static inline int syscall_get_arch(struct task_struct *task,
struct pt_regs *regs)
{
#ifdef CONFIG_IA32_EMULATION
/*
* TS_COMPAT is set for 32-bit syscall entry and then
* remains set until we return to user mode.
*
* TIF_IA32 tasks should always have TS_COMPAT set at
* system call time.
*
* x32 tasks should be considered AUDIT_ARCH_X86_64.
*/
if (task_thread_info(task)->status & TS_COMPAT)
return AUDIT_ARCH_I386;
#endif
/* Both x32 and x86_64 are considered "64-bit". */
return AUDIT_ARCH_X86_64;
}
#endif /* CONFIG_X86_32 */
#endif /* _ASM_X86_SYSCALL_H */
|
