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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Access to user system call parameters and results
4 *
5 * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
6 *
7 * See asm-generic/syscall.h for descriptions of what we must do here.
8 */
9
10#ifndef _ASM_X86_SYSCALL_H
11#define _ASM_X86_SYSCALL_H
12
13#include <uapi/linux/audit.h>
14#include <linux/sched.h>
15#include <linux/err.h>
16#include <asm/thread_info.h> /* for TS_COMPAT */
17#include <asm/unistd.h>
18
19typedef long (*sys_call_ptr_t)(const struct pt_regs *);
20extern const sys_call_ptr_t sys_call_table[];
21
22#if defined(CONFIG_X86_32)
23#define ia32_sys_call_table sys_call_table
24#else
25/*
26 * These may not exist, but still put the prototypes in so we
27 * can use IS_ENABLED().
28 */
29extern const sys_call_ptr_t ia32_sys_call_table[];
30extern const sys_call_ptr_t x32_sys_call_table[];
31#endif
32
33/*
34 * Only the low 32 bits of orig_ax are meaningful, so we return int.
35 * This importantly ignores the high bits on 64-bit, so comparisons
36 * sign-extend the low 32 bits.
37 */
38static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
39{
40 return regs->orig_ax;
41}
42
43static inline void syscall_rollback(struct task_struct *task,
44 struct pt_regs *regs)
45{
46 regs->ax = regs->orig_ax;
47}
48
49static inline long syscall_get_error(struct task_struct *task,
50 struct pt_regs *regs)
51{
52 unsigned long error = regs->ax;
53#ifdef CONFIG_IA32_EMULATION
54 /*
55 * TS_COMPAT is set for 32-bit syscall entries and then
56 * remains set until we return to user mode.
57 */
58 if (task->thread_info.status & (TS_COMPAT|TS_I386_REGS_POKED))
59 /*
60 * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
61 * and will match correctly in comparisons.
62 */
63 error = (long) (int) error;
64#endif
65 return IS_ERR_VALUE(error) ? error : 0;
66}
67
68static inline long syscall_get_return_value(struct task_struct *task,
69 struct pt_regs *regs)
70{
71 return regs->ax;
72}
73
74static inline void syscall_set_return_value(struct task_struct *task,
75 struct pt_regs *regs,
76 int error, long val)
77{
78 regs->ax = (long) error ?: val;
79}
80
81#ifdef CONFIG_X86_32
82
83static inline void syscall_get_arguments(struct task_struct *task,
84 struct pt_regs *regs,
85 unsigned long *args)
86{
87 memcpy(args, ®s->bx, 6 * sizeof(args[0]));
88}
89
90static inline int syscall_get_arch(struct task_struct *task)
91{
92 return AUDIT_ARCH_I386;
93}
94
95#else /* CONFIG_X86_64 */
96
97static inline void syscall_get_arguments(struct task_struct *task,
98 struct pt_regs *regs,
99 unsigned long *args)
100{
101# ifdef CONFIG_IA32_EMULATION
102 if (task->thread_info.status & TS_COMPAT) {
103 *args++ = regs->bx;
104 *args++ = regs->cx;
105 *args++ = regs->dx;
106 *args++ = regs->si;
107 *args++ = regs->di;
108 *args = regs->bp;
109 } else
110# endif
111 {
112 *args++ = regs->di;
113 *args++ = regs->si;
114 *args++ = regs->dx;
115 *args++ = regs->r10;
116 *args++ = regs->r8;
117 *args = regs->r9;
118 }
119}
120
121static inline int syscall_get_arch(struct task_struct *task)
122{
123 /* x32 tasks should be considered AUDIT_ARCH_X86_64. */
124 return (IS_ENABLED(CONFIG_IA32_EMULATION) &&
125 task->thread_info.status & TS_COMPAT)
126 ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64;
127}
128
129void do_syscall_64(struct pt_regs *regs, int nr);
130void do_int80_syscall_32(struct pt_regs *regs);
131long do_fast_syscall_32(struct pt_regs *regs);
132
133#endif /* CONFIG_X86_32 */
134
135#endif /* _ASM_X86_SYSCALL_H */
1/*
2 * Access to user system call parameters and results
3 *
4 * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
5 *
6 * This copyrighted material is made available to anyone wishing to use,
7 * modify, copy, or redistribute it subject to the terms and conditions
8 * of the GNU General Public License v.2.
9 *
10 * See asm-generic/syscall.h for descriptions of what we must do here.
11 */
12
13#ifndef _ASM_X86_SYSCALL_H
14#define _ASM_X86_SYSCALL_H
15
16#include <linux/sched.h>
17#include <linux/err.h>
18
19extern const unsigned long sys_call_table[];
20
21/*
22 * Only the low 32 bits of orig_ax are meaningful, so we return int.
23 * This importantly ignores the high bits on 64-bit, so comparisons
24 * sign-extend the low 32 bits.
25 */
26static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
27{
28 return regs->orig_ax;
29}
30
31static inline void syscall_rollback(struct task_struct *task,
32 struct pt_regs *regs)
33{
34 regs->ax = regs->orig_ax;
35}
36
37static inline long syscall_get_error(struct task_struct *task,
38 struct pt_regs *regs)
39{
40 unsigned long error = regs->ax;
41#ifdef CONFIG_IA32_EMULATION
42 /*
43 * TS_COMPAT is set for 32-bit syscall entries and then
44 * remains set until we return to user mode.
45 */
46 if (task_thread_info(task)->status & TS_COMPAT)
47 /*
48 * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
49 * and will match correctly in comparisons.
50 */
51 error = (long) (int) error;
52#endif
53 return IS_ERR_VALUE(error) ? error : 0;
54}
55
56static inline long syscall_get_return_value(struct task_struct *task,
57 struct pt_regs *regs)
58{
59 return regs->ax;
60}
61
62static inline void syscall_set_return_value(struct task_struct *task,
63 struct pt_regs *regs,
64 int error, long val)
65{
66 regs->ax = (long) error ?: val;
67}
68
69#ifdef CONFIG_X86_32
70
71static inline void syscall_get_arguments(struct task_struct *task,
72 struct pt_regs *regs,
73 unsigned int i, unsigned int n,
74 unsigned long *args)
75{
76 BUG_ON(i + n > 6);
77 memcpy(args, ®s->bx + i, n * sizeof(args[0]));
78}
79
80static inline void syscall_set_arguments(struct task_struct *task,
81 struct pt_regs *regs,
82 unsigned int i, unsigned int n,
83 const unsigned long *args)
84{
85 BUG_ON(i + n > 6);
86 memcpy(®s->bx + i, args, n * sizeof(args[0]));
87}
88
89#else /* CONFIG_X86_64 */
90
91static inline void syscall_get_arguments(struct task_struct *task,
92 struct pt_regs *regs,
93 unsigned int i, unsigned int n,
94 unsigned long *args)
95{
96# ifdef CONFIG_IA32_EMULATION
97 if (task_thread_info(task)->status & TS_COMPAT)
98 switch (i) {
99 case 0:
100 if (!n--) break;
101 *args++ = regs->bx;
102 case 1:
103 if (!n--) break;
104 *args++ = regs->cx;
105 case 2:
106 if (!n--) break;
107 *args++ = regs->dx;
108 case 3:
109 if (!n--) break;
110 *args++ = regs->si;
111 case 4:
112 if (!n--) break;
113 *args++ = regs->di;
114 case 5:
115 if (!n--) break;
116 *args++ = regs->bp;
117 case 6:
118 if (!n--) break;
119 default:
120 BUG();
121 break;
122 }
123 else
124# endif
125 switch (i) {
126 case 0:
127 if (!n--) break;
128 *args++ = regs->di;
129 case 1:
130 if (!n--) break;
131 *args++ = regs->si;
132 case 2:
133 if (!n--) break;
134 *args++ = regs->dx;
135 case 3:
136 if (!n--) break;
137 *args++ = regs->r10;
138 case 4:
139 if (!n--) break;
140 *args++ = regs->r8;
141 case 5:
142 if (!n--) break;
143 *args++ = regs->r9;
144 case 6:
145 if (!n--) break;
146 default:
147 BUG();
148 break;
149 }
150}
151
152static inline void syscall_set_arguments(struct task_struct *task,
153 struct pt_regs *regs,
154 unsigned int i, unsigned int n,
155 const unsigned long *args)
156{
157# ifdef CONFIG_IA32_EMULATION
158 if (task_thread_info(task)->status & TS_COMPAT)
159 switch (i) {
160 case 0:
161 if (!n--) break;
162 regs->bx = *args++;
163 case 1:
164 if (!n--) break;
165 regs->cx = *args++;
166 case 2:
167 if (!n--) break;
168 regs->dx = *args++;
169 case 3:
170 if (!n--) break;
171 regs->si = *args++;
172 case 4:
173 if (!n--) break;
174 regs->di = *args++;
175 case 5:
176 if (!n--) break;
177 regs->bp = *args++;
178 case 6:
179 if (!n--) break;
180 default:
181 BUG();
182 break;
183 }
184 else
185# endif
186 switch (i) {
187 case 0:
188 if (!n--) break;
189 regs->di = *args++;
190 case 1:
191 if (!n--) break;
192 regs->si = *args++;
193 case 2:
194 if (!n--) break;
195 regs->dx = *args++;
196 case 3:
197 if (!n--) break;
198 regs->r10 = *args++;
199 case 4:
200 if (!n--) break;
201 regs->r8 = *args++;
202 case 5:
203 if (!n--) break;
204 regs->r9 = *args++;
205 case 6:
206 if (!n--) break;
207 default:
208 BUG();
209 break;
210 }
211}
212
213#endif /* CONFIG_X86_32 */
214
215#endif /* _ASM_X86_SYSCALL_H */