xref: /openbmc/linux/sound/core/control_compat.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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 snd_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(struct snd_card *card,
35 				    struct snd_ctl_elem_list32 __user *data32)
36 {
37 	struct snd_ctl_elem_list __user *data;
38 	compat_caddr_t ptr;
39 	int err;
40 
41 	data = compat_alloc_user_space(sizeof(*data));
42 
43 	/* offset, space, used, count */
44 	if (copy_in_user(data, data32, 4 * sizeof(u32)))
45 		return -EFAULT;
46 	/* pids */
47 	if (get_user(ptr, &data32->pids) ||
48 	    put_user(compat_ptr(ptr), &data->pids))
49 		return -EFAULT;
50 	err = snd_ctl_elem_list(card, data);
51 	if (err < 0)
52 		return err;
53 	/* copy the result */
54 	if (copy_in_user(data32, data, 4 * sizeof(u32)))
55 		return -EFAULT;
56 	return 0;
57 }
58 
59 /*
60  * control element info
61  * it uses union, so the things are not easy..
62  */
63 
64 struct snd_ctl_elem_info32 {
65 	struct snd_ctl_elem_id id; // the size of struct is same
66 	s32 type;
67 	u32 access;
68 	u32 count;
69 	s32 owner;
70 	union {
71 		struct {
72 			s32 min;
73 			s32 max;
74 			s32 step;
75 		} integer;
76 		struct {
77 			u64 min;
78 			u64 max;
79 			u64 step;
80 		} integer64;
81 		struct {
82 			u32 items;
83 			u32 item;
84 			char name[64];
85 		} enumerated;
86 		unsigned char reserved[128];
87 	} value;
88 	unsigned char reserved[64];
89 } __attribute__((packed));
90 
91 static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
92 				    struct snd_ctl_elem_info32 __user *data32)
93 {
94 	struct snd_ctl_elem_info *data;
95 	int err;
96 
97 	data = kzalloc(sizeof(*data), GFP_KERNEL);
98 	if (! data)
99 		return -ENOMEM;
100 
101 	err = -EFAULT;
102 	/* copy id */
103 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
104 		goto error;
105 	/* we need to copy the item index.
106 	 * hope this doesn't break anything..
107 	 */
108 	if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
109 		goto error;
110 
111 	snd_power_lock(ctl->card);
112 	err = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
113 	if (err >= 0)
114 		err = snd_ctl_elem_info(ctl, data);
115 	snd_power_unlock(ctl->card);
116 
117 	if (err < 0)
118 		goto error;
119 	/* restore info to 32bit */
120 	err = -EFAULT;
121 	/* id, type, access, count */
122 	if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
123 	    copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
124 		goto error;
125 	if (put_user(data->owner, &data32->owner))
126 		goto error;
127 	switch (data->type) {
128 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
129 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
130 		if (put_user(data->value.integer.min, &data32->value.integer.min) ||
131 		    put_user(data->value.integer.max, &data32->value.integer.max) ||
132 		    put_user(data->value.integer.step, &data32->value.integer.step))
133 			goto error;
134 		break;
135 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
136 		if (copy_to_user(&data32->value.integer64,
137 				 &data->value.integer64,
138 				 sizeof(data->value.integer64)))
139 			goto error;
140 		break;
141 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
142 		if (copy_to_user(&data32->value.enumerated,
143 				 &data->value.enumerated,
144 				 sizeof(data->value.enumerated)))
145 			goto error;
146 		break;
147 	default:
148 		break;
149 	}
150 	err = 0;
151  error:
152 	kfree(data);
153 	return err;
154 }
155 
156 /* read / write */
157 struct snd_ctl_elem_value32 {
158 	struct snd_ctl_elem_id id;
159 	unsigned int indirect;	/* bit-field causes misalignment */
160         union {
161 		s32 integer[128];
162 		unsigned char data[512];
163 #ifndef CONFIG_X86_64
164 		s64 integer64[64];
165 #endif
166         } value;
167         unsigned char reserved[128];
168 };
169 
170 
171 /* get the value type and count of the control */
172 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
173 			int *countp)
174 {
175 	struct snd_kcontrol *kctl;
176 	struct snd_ctl_elem_info *info;
177 	int err;
178 
179 	down_read(&card->controls_rwsem);
180 	kctl = snd_ctl_find_id(card, id);
181 	if (! kctl) {
182 		up_read(&card->controls_rwsem);
183 		return -ENXIO;
184 	}
185 	info = kzalloc(sizeof(*info), GFP_KERNEL);
186 	if (info == NULL) {
187 		up_read(&card->controls_rwsem);
188 		return -ENOMEM;
189 	}
190 	info->id = *id;
191 	err = kctl->info(kctl, info);
192 	up_read(&card->controls_rwsem);
193 	if (err >= 0) {
194 		err = info->type;
195 		*countp = info->count;
196 	}
197 	kfree(info);
198 	return err;
199 }
200 
201 static int get_elem_size(int type, int count)
202 {
203 	switch (type) {
204 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
205 		return sizeof(s64) * count;
206 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
207 		return sizeof(int) * count;
208 	case SNDRV_CTL_ELEM_TYPE_BYTES:
209 		return 512;
210 	case SNDRV_CTL_ELEM_TYPE_IEC958:
211 		return sizeof(struct snd_aes_iec958);
212 	default:
213 		return -1;
214 	}
215 }
216 
217 static int copy_ctl_value_from_user(struct snd_card *card,
218 				    struct snd_ctl_elem_value *data,
219 				    struct snd_ctl_elem_value32 __user *data32,
220 				    int *typep, int *countp)
221 {
222 	int i, type, count, size;
223 	unsigned int indirect;
224 
225 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
226 		return -EFAULT;
227 	if (get_user(indirect, &data32->indirect))
228 		return -EFAULT;
229 	if (indirect)
230 		return -EINVAL;
231 	type = get_ctl_type(card, &data->id, &count);
232 	if (type < 0)
233 		return type;
234 
235 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
236 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
237 		for (i = 0; i < count; i++) {
238 			int val;
239 			if (get_user(val, &data32->value.integer[i]))
240 				return -EFAULT;
241 			data->value.integer.value[i] = val;
242 		}
243 	} else {
244 		size = get_elem_size(type, count);
245 		if (size < 0) {
246 			printk(KERN_ERR "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
247 			return -EINVAL;
248 		}
249 		if (copy_from_user(data->value.bytes.data,
250 				   data32->value.data, size))
251 			return -EFAULT;
252 	}
253 
254 	*typep = type;
255 	*countp = count;
256 	return 0;
257 }
258 
259 /* restore the value to 32bit */
260 static int copy_ctl_value_to_user(struct snd_ctl_elem_value32 __user *data32,
261 				  struct snd_ctl_elem_value *data,
262 				  int type, int count)
263 {
264 	int i, size;
265 
266 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
267 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
268 		for (i = 0; i < count; i++) {
269 			int val;
270 			val = data->value.integer.value[i];
271 			if (put_user(val, &data32->value.integer[i]))
272 				return -EFAULT;
273 		}
274 	} else {
275 		size = get_elem_size(type, count);
276 		if (copy_to_user(data32->value.data,
277 				 data->value.bytes.data, size))
278 			return -EFAULT;
279 	}
280 	return 0;
281 }
282 
283 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
284 					 struct snd_ctl_elem_value32 __user *data32)
285 {
286 	struct snd_ctl_elem_value *data;
287 	int err, type, count;
288 
289 	data = kzalloc(sizeof(*data), GFP_KERNEL);
290 	if (data == NULL)
291 		return -ENOMEM;
292 
293 	if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
294 		goto error;
295 
296 	snd_power_lock(card);
297 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
298 	if (err >= 0)
299 		err = snd_ctl_elem_read(card, data);
300 	snd_power_unlock(card);
301 	if (err >= 0)
302 		err = copy_ctl_value_to_user(data32, data, type, count);
303  error:
304 	kfree(data);
305 	return err;
306 }
307 
308 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
309 					  struct snd_ctl_elem_value32 __user *data32)
310 {
311 	struct snd_ctl_elem_value *data;
312 	struct snd_card *card = file->card;
313 	int err, type, count;
314 
315 	data = kzalloc(sizeof(*data), GFP_KERNEL);
316 	if (data == NULL)
317 		return -ENOMEM;
318 
319 	if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
320 		goto error;
321 
322 	snd_power_lock(card);
323 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
324 	if (err >= 0)
325 		err = snd_ctl_elem_write(card, file, data);
326 	snd_power_unlock(card);
327 	if (err >= 0)
328 		err = copy_ctl_value_to_user(data32, data, type, count);
329  error:
330 	kfree(data);
331 	return err;
332 }
333 
334 /* add or replace a user control */
335 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
336 				   struct snd_ctl_elem_info32 __user *data32,
337 				   int replace)
338 {
339 	struct snd_ctl_elem_info *data;
340 	int err;
341 
342 	data = kzalloc(sizeof(*data), GFP_KERNEL);
343 	if (! data)
344 		return -ENOMEM;
345 
346 	err = -EFAULT;
347 	/* id, type, access, count */ \
348 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
349 	    copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
350 		goto error;
351 	if (get_user(data->owner, &data32->owner) ||
352 	    get_user(data->type, &data32->type))
353 		goto error;
354 	switch (data->type) {
355 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
356 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
357 		if (get_user(data->value.integer.min, &data32->value.integer.min) ||
358 		    get_user(data->value.integer.max, &data32->value.integer.max) ||
359 		    get_user(data->value.integer.step, &data32->value.integer.step))
360 			goto error;
361 		break;
362 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
363 		if (copy_from_user(&data->value.integer64,
364 				   &data32->value.integer64,
365 				   sizeof(data->value.integer64)))
366 			goto error;
367 		break;
368 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
369 		if (copy_from_user(&data->value.enumerated,
370 				   &data32->value.enumerated,
371 				   sizeof(data->value.enumerated)))
372 			goto error;
373 		break;
374 	default:
375 		break;
376 	}
377 	err = snd_ctl_elem_add(file, data, replace);
378  error:
379 	kfree(data);
380 	return err;
381 }
382 
383 enum {
384 	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
385 	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
386 	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
387 	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
388 	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
389 	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
390 };
391 
392 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
393 {
394 	struct snd_ctl_file *ctl;
395 	struct snd_kctl_ioctl *p;
396 	void __user *argp = compat_ptr(arg);
397 	int err;
398 
399 	ctl = file->private_data;
400 	snd_assert(ctl && ctl->card, return -ENXIO);
401 
402 	switch (cmd) {
403 	case SNDRV_CTL_IOCTL_PVERSION:
404 	case SNDRV_CTL_IOCTL_CARD_INFO:
405 	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
406 	case SNDRV_CTL_IOCTL_POWER:
407 	case SNDRV_CTL_IOCTL_POWER_STATE:
408 	case SNDRV_CTL_IOCTL_ELEM_LOCK:
409 	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
410 	case SNDRV_CTL_IOCTL_ELEM_REMOVE:
411 	case SNDRV_CTL_IOCTL_TLV_READ:
412 	case SNDRV_CTL_IOCTL_TLV_WRITE:
413 	case SNDRV_CTL_IOCTL_TLV_COMMAND:
414 		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
415 	case SNDRV_CTL_IOCTL_ELEM_LIST32:
416 		return snd_ctl_elem_list_compat(ctl->card, argp);
417 	case SNDRV_CTL_IOCTL_ELEM_INFO32:
418 		return snd_ctl_elem_info_compat(ctl, argp);
419 	case SNDRV_CTL_IOCTL_ELEM_READ32:
420 		return snd_ctl_elem_read_user_compat(ctl->card, argp);
421 	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
422 		return snd_ctl_elem_write_user_compat(ctl, argp);
423 	case SNDRV_CTL_IOCTL_ELEM_ADD32:
424 		return snd_ctl_elem_add_compat(ctl, argp, 0);
425 	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
426 		return snd_ctl_elem_add_compat(ctl, argp, 1);
427 	}
428 
429 	down_read(&snd_ioctl_rwsem);
430 	list_for_each_entry(p, &snd_control_compat_ioctls, list) {
431 		if (p->fioctl) {
432 			err = p->fioctl(ctl->card, ctl, cmd, arg);
433 			if (err != -ENOIOCTLCMD) {
434 				up_read(&snd_ioctl_rwsem);
435 				return err;
436 			}
437 		}
438 	}
439 	up_read(&snd_ioctl_rwsem);
440 	return -ENOIOCTLCMD;
441 }
442