xref: /openbmc/linux/sound/core/rawmidi_compat.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   32bit -> 64bit ioctl wrapper for raw MIDI API
4  *   Copyright (c) by Takashi Iwai <tiwai@suse.de>
5  */
6 
7 /* This file included from rawmidi.c */
8 
9 #include <linux/compat.h>
10 
11 struct snd_rawmidi_params32 {
12 	s32 stream;
13 	u32 buffer_size;
14 	u32 avail_min;
15 	unsigned int no_active_sensing; /* avoid bit-field */
16 	unsigned char reserved[16];
17 } __attribute__((packed));
18 
19 static int snd_rawmidi_ioctl_params_compat(struct snd_rawmidi_file *rfile,
20 					   struct snd_rawmidi_params32 __user *src)
21 {
22 	struct snd_rawmidi_params params;
23 	unsigned int val;
24 
25 	if (get_user(params.stream, &src->stream) ||
26 	    get_user(params.buffer_size, &src->buffer_size) ||
27 	    get_user(params.avail_min, &src->avail_min) ||
28 	    get_user(val, &src->no_active_sensing))
29 		return -EFAULT;
30 	params.no_active_sensing = val;
31 	switch (params.stream) {
32 	case SNDRV_RAWMIDI_STREAM_OUTPUT:
33 		if (!rfile->output)
34 			return -EINVAL;
35 		return snd_rawmidi_output_params(rfile->output, &params);
36 	case SNDRV_RAWMIDI_STREAM_INPUT:
37 		if (!rfile->input)
38 			return -EINVAL;
39 		return snd_rawmidi_input_params(rfile->input, &params);
40 	}
41 	return -EINVAL;
42 }
43 
44 struct snd_rawmidi_status32 {
45 	s32 stream;
46 	struct compat_timespec tstamp;
47 	u32 avail;
48 	u32 xruns;
49 	unsigned char reserved[16];
50 } __attribute__((packed));
51 
52 static int snd_rawmidi_ioctl_status_compat(struct snd_rawmidi_file *rfile,
53 					   struct snd_rawmidi_status32 __user *src)
54 {
55 	int err;
56 	struct snd_rawmidi_status status;
57 
58 	if (get_user(status.stream, &src->stream))
59 		return -EFAULT;
60 
61 	switch (status.stream) {
62 	case SNDRV_RAWMIDI_STREAM_OUTPUT:
63 		if (!rfile->output)
64 			return -EINVAL;
65 		err = snd_rawmidi_output_status(rfile->output, &status);
66 		break;
67 	case SNDRV_RAWMIDI_STREAM_INPUT:
68 		if (!rfile->input)
69 			return -EINVAL;
70 		err = snd_rawmidi_input_status(rfile->input, &status);
71 		break;
72 	default:
73 		return -EINVAL;
74 	}
75 	if (err < 0)
76 		return err;
77 
78 	if (compat_put_timespec(&status.tstamp, &src->tstamp) ||
79 	    put_user(status.avail, &src->avail) ||
80 	    put_user(status.xruns, &src->xruns))
81 		return -EFAULT;
82 
83 	return 0;
84 }
85 
86 #ifdef CONFIG_X86_X32
87 /* X32 ABI has 64bit timespec and 64bit alignment */
88 struct snd_rawmidi_status_x32 {
89 	s32 stream;
90 	u32 rsvd; /* alignment */
91 	struct timespec tstamp;
92 	u32 avail;
93 	u32 xruns;
94 	unsigned char reserved[16];
95 } __attribute__((packed));
96 
97 #define put_timespec(src, dst) copy_to_user(dst, src, sizeof(*dst))
98 
99 static int snd_rawmidi_ioctl_status_x32(struct snd_rawmidi_file *rfile,
100 					struct snd_rawmidi_status_x32 __user *src)
101 {
102 	int err;
103 	struct snd_rawmidi_status status;
104 
105 	if (get_user(status.stream, &src->stream))
106 		return -EFAULT;
107 
108 	switch (status.stream) {
109 	case SNDRV_RAWMIDI_STREAM_OUTPUT:
110 		if (!rfile->output)
111 			return -EINVAL;
112 		err = snd_rawmidi_output_status(rfile->output, &status);
113 		break;
114 	case SNDRV_RAWMIDI_STREAM_INPUT:
115 		if (!rfile->input)
116 			return -EINVAL;
117 		err = snd_rawmidi_input_status(rfile->input, &status);
118 		break;
119 	default:
120 		return -EINVAL;
121 	}
122 	if (err < 0)
123 		return err;
124 
125 	if (put_timespec(&status.tstamp, &src->tstamp) ||
126 	    put_user(status.avail, &src->avail) ||
127 	    put_user(status.xruns, &src->xruns))
128 		return -EFAULT;
129 
130 	return 0;
131 }
132 #endif /* CONFIG_X86_X32 */
133 
134 enum {
135 	SNDRV_RAWMIDI_IOCTL_PARAMS32 = _IOWR('W', 0x10, struct snd_rawmidi_params32),
136 	SNDRV_RAWMIDI_IOCTL_STATUS32 = _IOWR('W', 0x20, struct snd_rawmidi_status32),
137 #ifdef CONFIG_X86_X32
138 	SNDRV_RAWMIDI_IOCTL_STATUS_X32 = _IOWR('W', 0x20, struct snd_rawmidi_status_x32),
139 #endif /* CONFIG_X86_X32 */
140 };
141 
142 static long snd_rawmidi_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
143 {
144 	struct snd_rawmidi_file *rfile;
145 	void __user *argp = compat_ptr(arg);
146 
147 	rfile = file->private_data;
148 	switch (cmd) {
149 	case SNDRV_RAWMIDI_IOCTL_PVERSION:
150 	case SNDRV_RAWMIDI_IOCTL_INFO:
151 	case SNDRV_RAWMIDI_IOCTL_DROP:
152 	case SNDRV_RAWMIDI_IOCTL_DRAIN:
153 		return snd_rawmidi_ioctl(file, cmd, (unsigned long)argp);
154 	case SNDRV_RAWMIDI_IOCTL_PARAMS32:
155 		return snd_rawmidi_ioctl_params_compat(rfile, argp);
156 	case SNDRV_RAWMIDI_IOCTL_STATUS32:
157 		return snd_rawmidi_ioctl_status_compat(rfile, argp);
158 #ifdef CONFIG_X86_X32
159 	case SNDRV_RAWMIDI_IOCTL_STATUS_X32:
160 		return snd_rawmidi_ioctl_status_x32(rfile, argp);
161 #endif /* CONFIG_X86_X32 */
162 	}
163 	return -ENOIOCTLCMD;
164 }
165