xref: /openbmc/linux/sound/core/control_compat.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * compat ioctls for control API
3  *
4  *   Copyright (c) by Takashi Iwai <tiwai@suse.de>
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  *   This program is distributed in the hope that it will be useful,
12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *   GNU General Public License for more details.
15  *
16  *   You should have received a copy of the GNU General Public License
17  *   along with this program; if not, write to the Free Software
18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
19  */
20 
21 /* this file included from control.c */
22 
23 #include <linux/compat.h>
24 
25 struct sndrv_ctl_elem_list32 {
26 	u32 offset;
27 	u32 space;
28 	u32 used;
29 	u32 count;
30 	u32 pids;
31 	unsigned char reserved[50];
32 } /* don't set packed attribute here */;
33 
34 static int snd_ctl_elem_list_compat(snd_card_t *card, struct sndrv_ctl_elem_list32 __user *data32)
35 {
36 	struct sndrv_ctl_elem_list __user *data;
37 	compat_caddr_t ptr;
38 	int err;
39 
40 	data = compat_alloc_user_space(sizeof(*data));
41 
42 	/* offset, space, used, count */
43 	if (copy_in_user(data, data32, 4 * sizeof(u32)))
44 		return -EFAULT;
45 	/* pids */
46 	if (get_user(ptr, &data32->pids) ||
47 	    put_user(compat_ptr(ptr), &data->pids))
48 		return -EFAULT;
49 	err = snd_ctl_elem_list(card, data);
50 	if (err < 0)
51 		return err;
52 	/* copy the result */
53 	if (copy_in_user(data32, data, 4 * sizeof(u32)))
54 		return -EFAULT;
55 	return 0;
56 }
57 
58 /*
59  * control element info
60  * it uses union, so the things are not easy..
61  */
62 
63 struct sndrv_ctl_elem_info32 {
64 	struct sndrv_ctl_elem_id id; // the size of struct is same
65 	s32 type;
66 	u32 access;
67 	u32 count;
68 	s32 owner;
69 	union {
70 		struct {
71 			s32 min;
72 			s32 max;
73 			s32 step;
74 		} integer;
75 		struct {
76 			u64 min;
77 			u64 max;
78 			u64 step;
79 		} integer64;
80 		struct {
81 			u32 items;
82 			u32 item;
83 			char name[64];
84 		} enumerated;
85 		unsigned char reserved[128];
86 	} value;
87 	unsigned char reserved[64];
88 } __attribute__((packed));
89 
90 static int snd_ctl_elem_info_compat(snd_ctl_file_t *ctl, struct sndrv_ctl_elem_info32 __user *data32)
91 {
92 	struct sndrv_ctl_elem_info *data;
93 	int err;
94 
95 	data = kcalloc(1, sizeof(*data), GFP_KERNEL);
96 	if (! data)
97 		return -ENOMEM;
98 
99 	err = -EFAULT;
100 	/* copy id */
101 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
102 		goto error;
103 	/* we need to copy the item index.
104 	 * hope this doesn't break anything..
105 	 */
106 	if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
107 		goto error;
108 	err = snd_ctl_elem_info(ctl, data);
109 	if (err < 0)
110 		goto error;
111 	/* restore info to 32bit */
112 	err = -EFAULT;
113 	/* id, type, access, count */
114 	if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
115 	    copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
116 		goto error;
117 	if (put_user(data->owner, &data32->owner))
118 		goto error;
119 	switch (data->type) {
120 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
121 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
122 		if (put_user(data->value.integer.min, &data32->value.integer.min) ||
123 		    put_user(data->value.integer.max, &data32->value.integer.max) ||
124 		    put_user(data->value.integer.step, &data32->value.integer.step))
125 			goto error;
126 		break;
127 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
128 		if (copy_to_user(&data32->value.integer64,
129 				 &data->value.integer64,
130 				 sizeof(data->value.integer64)))
131 			goto error;
132 		break;
133 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
134 		if (copy_to_user(&data32->value.enumerated,
135 				 &data->value.enumerated,
136 				 sizeof(data->value.enumerated)))
137 			goto error;
138 		break;
139 	default:
140 		break;
141 	}
142 	err = 0;
143  error:
144 	kfree(data);
145 	return err;
146 }
147 
148 /* read / write */
149 struct sndrv_ctl_elem_value32 {
150 	struct sndrv_ctl_elem_id id;
151 	unsigned int indirect;	/* bit-field causes misalignment */
152         union {
153 		s32 integer[128];
154 		unsigned char data[512];
155 #ifndef CONFIG_X86_64
156 		s64 integer64[64];
157 #endif
158         } value;
159         unsigned char reserved[128];
160 };
161 
162 
163 /* get the value type and count of the control */
164 static int get_ctl_type(snd_card_t *card, snd_ctl_elem_id_t *id, int *countp)
165 {
166 	snd_kcontrol_t *kctl;
167 	snd_ctl_elem_info_t info;
168 	int err;
169 
170 	down_read(&card->controls_rwsem);
171 	kctl = snd_ctl_find_id(card, id);
172 	if (! kctl) {
173 		up_read(&card->controls_rwsem);
174 		return -ENXIO;
175 	}
176 	info.id = *id;
177 	err = kctl->info(kctl, &info);
178 	up_read(&card->controls_rwsem);
179 	if (err >= 0) {
180 		err = info.type;
181 		*countp = info.count;
182 	}
183 	return err;
184 }
185 
186 static int get_elem_size(int type, int count)
187 {
188 	switch (type) {
189 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
190 		return sizeof(s64) * count;
191 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
192 		return sizeof(int) * count;
193 	case SNDRV_CTL_ELEM_TYPE_BYTES:
194 		return 512;
195 	case SNDRV_CTL_ELEM_TYPE_IEC958:
196 		return sizeof(struct sndrv_aes_iec958);
197 	default:
198 		return -1;
199 	}
200 }
201 
202 static int copy_ctl_value_from_user(snd_card_t *card,
203 				    struct sndrv_ctl_elem_value *data,
204 				    struct sndrv_ctl_elem_value32 __user *data32,
205 				    int *typep, int *countp)
206 {
207 	int i, type, count, size;
208 	unsigned int indirect;
209 
210 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
211 		return -EFAULT;
212 	if (get_user(indirect, &data32->indirect))
213 		return -EFAULT;
214 	if (indirect)
215 		return -EINVAL;
216 	type = get_ctl_type(card, &data->id, &count);
217 	if (type < 0)
218 		return type;
219 
220 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
221 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
222 		for (i = 0; i < count; i++) {
223 			int val;
224 			if (get_user(val, &data32->value.integer[i]))
225 				return -EFAULT;
226 			data->value.integer.value[i] = val;
227 		}
228 	} else {
229 		size = get_elem_size(type, count);
230 		if (size < 0) {
231 			printk(KERN_ERR "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
232 			return -EINVAL;
233 		}
234 		if (copy_from_user(data->value.bytes.data,
235 				   data32->value.data, size))
236 			return -EFAULT;
237 	}
238 
239 	*typep = type;
240 	*countp = count;
241 	return 0;
242 }
243 
244 /* restore the value to 32bit */
245 static int copy_ctl_value_to_user(struct sndrv_ctl_elem_value32 __user *data32,
246 				  struct sndrv_ctl_elem_value *data,
247 				  int type, int count)
248 {
249 	int i, size;
250 
251 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
252 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
253 		for (i = 0; i < count; i++) {
254 			int val;
255 			val = data->value.integer.value[i];
256 			if (put_user(val, &data32->value.integer[i]))
257 				return -EFAULT;
258 		}
259 	} else {
260 		size = get_elem_size(type, count);
261 		if (copy_to_user(data32->value.data,
262 				 data->value.bytes.data, size))
263 			return -EFAULT;
264 	}
265 	return 0;
266 }
267 
268 static int snd_ctl_elem_read_user_compat(snd_card_t *card,
269 					 struct sndrv_ctl_elem_value32 __user *data32)
270 {
271 	struct sndrv_ctl_elem_value *data;
272 	int err, type, count;
273 
274 	data = kcalloc(1, sizeof(*data), GFP_KERNEL);
275 	if (data == NULL)
276 		return -ENOMEM;
277 
278 	if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
279 		goto error;
280 	if ((err = snd_ctl_elem_read(card, data)) < 0)
281 		goto error;
282 	err = copy_ctl_value_to_user(data32, data, type, count);
283  error:
284 	kfree(data);
285 	return err;
286 }
287 
288 static int snd_ctl_elem_write_user_compat(snd_ctl_file_t *file,
289 					  struct sndrv_ctl_elem_value32 __user *data32)
290 {
291 	struct sndrv_ctl_elem_value *data;
292 	int err, type, count;
293 
294 	data = kcalloc(1, sizeof(*data), GFP_KERNEL);
295 	if (data == NULL)
296 		return -ENOMEM;
297 
298 	if ((err = copy_ctl_value_from_user(file->card, data, data32, &type, &count)) < 0)
299 		goto error;
300 	if ((err = snd_ctl_elem_write(file->card, file, data)) < 0)
301 		goto error;
302 	err = copy_ctl_value_to_user(data32, data, type, count);
303  error:
304 	kfree(data);
305 	return err;
306 }
307 
308 /* add or replace a user control */
309 static int snd_ctl_elem_add_compat(snd_ctl_file_t *file,
310 				   struct sndrv_ctl_elem_info32 __user *data32,
311 				   int replace)
312 {
313 	struct sndrv_ctl_elem_info *data;
314 	int err;
315 
316 	data = kcalloc(1, sizeof(*data), GFP_KERNEL);
317 	if (! data)
318 		return -ENOMEM;
319 
320 	err = -EFAULT;
321 	/* id, type, access, count */ \
322 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
323 	    copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
324 		goto error;
325 	if (get_user(data->owner, &data32->owner) ||
326 	    get_user(data->type, &data32->type))
327 		goto error;
328 	switch (data->type) {
329 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
330 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
331 		if (get_user(data->value.integer.min, &data32->value.integer.min) ||
332 		    get_user(data->value.integer.max, &data32->value.integer.max) ||
333 		    get_user(data->value.integer.step, &data32->value.integer.step))
334 			goto error;
335 		break;
336 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
337 		if (copy_from_user(&data->value.integer64,
338 				   &data32->value.integer64,
339 				   sizeof(data->value.integer64)))
340 			goto error;
341 		break;
342 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
343 		if (copy_from_user(&data->value.enumerated,
344 				   &data32->value.enumerated,
345 				   sizeof(data->value.enumerated)))
346 			goto error;
347 		break;
348 	default:
349 		break;
350 	}
351 	err = snd_ctl_elem_add(file, data, replace);
352  error:
353 	kfree(data);
354 	return err;
355 }
356 
357 enum {
358 	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct sndrv_ctl_elem_list32),
359 	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct sndrv_ctl_elem_info32),
360 	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct sndrv_ctl_elem_value32),
361 	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct sndrv_ctl_elem_value32),
362 	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct sndrv_ctl_elem_info32),
363 	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct sndrv_ctl_elem_info32),
364 };
365 
366 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
367 {
368 	snd_ctl_file_t *ctl;
369 	struct list_head *list;
370 	void __user *argp = compat_ptr(arg);
371 	int err;
372 
373 	ctl = file->private_data;
374 	snd_assert(ctl && ctl->card, return -ENXIO);
375 
376 	switch (cmd) {
377 	case SNDRV_CTL_IOCTL_PVERSION:
378 	case SNDRV_CTL_IOCTL_CARD_INFO:
379 	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
380 	case SNDRV_CTL_IOCTL_POWER:
381 	case SNDRV_CTL_IOCTL_POWER_STATE:
382 	case SNDRV_CTL_IOCTL_ELEM_LOCK:
383 	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
384 		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
385 	case SNDRV_CTL_IOCTL_ELEM_LIST32:
386 		return snd_ctl_elem_list_compat(ctl->card, argp);
387 	case SNDRV_CTL_IOCTL_ELEM_INFO32:
388 		return snd_ctl_elem_info_compat(ctl, argp);
389 	case SNDRV_CTL_IOCTL_ELEM_READ32:
390 		return snd_ctl_elem_read_user_compat(ctl->card, argp);
391 	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
392 		return snd_ctl_elem_write_user_compat(ctl, argp);
393 	case SNDRV_CTL_IOCTL_ELEM_ADD32:
394 		return snd_ctl_elem_add_compat(ctl, argp, 0);
395 	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
396 		return snd_ctl_elem_add_compat(ctl, argp, 1);
397 	}
398 
399 	down_read(&snd_ioctl_rwsem);
400 	list_for_each(list, &snd_control_compat_ioctls) {
401 		snd_kctl_ioctl_t *p = list_entry(list, snd_kctl_ioctl_t, list);
402 		if (p->fioctl) {
403 			err = p->fioctl(ctl->card, ctl, cmd, arg);
404 			if (err != -ENOIOCTLCMD) {
405 				up_read(&snd_ioctl_rwsem);
406 				return err;
407 			}
408 		}
409 	}
410 	up_read(&snd_ioctl_rwsem);
411 	return -ENOIOCTLCMD;
412 }
413