1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * 32bit compatibility wrappers for the input subsystem.
4 *
5 * Very heavily based on evdev.c - Copyright (c) 1999-2002 Vojtech Pavlik
6 */
7
8#include <linux/export.h>
9#include <linux/uaccess.h>
10#include "input-compat.h"
11
12#ifdef CONFIG_COMPAT
13
14int input_event_from_user(const char __user *buffer,
15 struct input_event *event)
16{
17 if (in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
18 struct input_event_compat compat_event;
19
20 if (copy_from_user(to: &compat_event, from: buffer,
21 n: sizeof(struct input_event_compat)))
22 return -EFAULT;
23
24 event->input_event_sec = compat_event.sec;
25 event->input_event_usec = compat_event.usec;
26 event->type = compat_event.type;
27 event->code = compat_event.code;
28 event->value = compat_event.value;
29
30 } else {
31 if (copy_from_user(to: event, from: buffer, n: sizeof(struct input_event)))
32 return -EFAULT;
33 }
34
35 return 0;
36}
37
38int input_event_to_user(char __user *buffer,
39 const struct input_event *event)
40{
41 if (in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
42 struct input_event_compat compat_event;
43
44 compat_event.sec = event->input_event_sec;
45 compat_event.usec = event->input_event_usec;
46 compat_event.type = event->type;
47 compat_event.code = event->code;
48 compat_event.value = event->value;
49
50 if (copy_to_user(to: buffer, from: &compat_event,
51 n: sizeof(struct input_event_compat)))
52 return -EFAULT;
53
54 } else {
55 if (copy_to_user(to: buffer, from: event, n: sizeof(struct input_event)))
56 return -EFAULT;
57 }
58
59 return 0;
60}
61
62int input_ff_effect_from_user(const char __user *buffer, size_t size,
63 struct ff_effect *effect)
64{
65 if (in_compat_syscall()) {
66 struct ff_effect_compat *compat_effect;
67
68 if (size != sizeof(struct ff_effect_compat))
69 return -EINVAL;
70
71 /*
72 * It so happens that the pointer which needs to be changed
73 * is the last field in the structure, so we can retrieve the
74 * whole thing and replace just the pointer.
75 */
76 compat_effect = (struct ff_effect_compat *)effect;
77
78 if (copy_from_user(to: compat_effect, from: buffer,
79 n: sizeof(struct ff_effect_compat)))
80 return -EFAULT;
81
82 if (compat_effect->type == FF_PERIODIC &&
83 compat_effect->u.periodic.waveform == FF_CUSTOM)
84 effect->u.periodic.custom_data =
85 compat_ptr(uptr: compat_effect->u.periodic.custom_data);
86 } else {
87 if (size != sizeof(struct ff_effect))
88 return -EINVAL;
89
90 if (copy_from_user(to: effect, from: buffer, n: sizeof(struct ff_effect)))
91 return -EFAULT;
92 }
93
94 return 0;
95}
96
97#else
98
99int input_event_from_user(const char __user *buffer,
100 struct input_event *event)
101{
102 if (copy_from_user(event, buffer, sizeof(struct input_event)))
103 return -EFAULT;
104
105 return 0;
106}
107
108int input_event_to_user(char __user *buffer,
109 const struct input_event *event)
110{
111 if (copy_to_user(buffer, event, sizeof(struct input_event)))
112 return -EFAULT;
113
114 return 0;
115}
116
117int input_ff_effect_from_user(const char __user *buffer, size_t size,
118 struct ff_effect *effect)
119{
120 if (size != sizeof(struct ff_effect))
121 return -EINVAL;
122
123 if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
124 return -EFAULT;
125
126 return 0;
127}
128
129#endif /* CONFIG_COMPAT */
130
131EXPORT_SYMBOL_GPL(input_event_from_user);
132EXPORT_SYMBOL_GPL(input_event_to_user);
133EXPORT_SYMBOL_GPL(input_ff_effect_from_user);
134

source code of linux/drivers/input/input-compat.c