xref: /openbmc/linux/sound/core/control_compat.c (revision f3539c12)
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 #include <linux/slab.h>
25 
26 struct snd_ctl_elem_list32 {
27 	u32 offset;
28 	u32 space;
29 	u32 used;
30 	u32 count;
31 	u32 pids;
32 	unsigned char reserved[50];
33 } /* don't set packed attribute here */;
34 
35 static int snd_ctl_elem_list_compat(struct snd_card *card,
36 				    struct snd_ctl_elem_list32 __user *data32)
37 {
38 	struct snd_ctl_elem_list __user *data;
39 	compat_caddr_t ptr;
40 	int err;
41 
42 	data = compat_alloc_user_space(sizeof(*data));
43 
44 	/* offset, space, used, count */
45 	if (copy_in_user(data, data32, 4 * sizeof(u32)))
46 		return -EFAULT;
47 	/* pids */
48 	if (get_user(ptr, &data32->pids) ||
49 	    put_user(compat_ptr(ptr), &data->pids))
50 		return -EFAULT;
51 	err = snd_ctl_elem_list(card, data);
52 	if (err < 0)
53 		return err;
54 	/* copy the result */
55 	if (copy_in_user(data32, data, 4 * sizeof(u32)))
56 		return -EFAULT;
57 	return 0;
58 }
59 
60 /*
61  * control element info
62  * it uses union, so the things are not easy..
63  */
64 
65 struct snd_ctl_elem_info32 {
66 	struct snd_ctl_elem_id id; // the size of struct is same
67 	s32 type;
68 	u32 access;
69 	u32 count;
70 	s32 owner;
71 	union {
72 		struct {
73 			s32 min;
74 			s32 max;
75 			s32 step;
76 		} integer;
77 		struct {
78 			u64 min;
79 			u64 max;
80 			u64 step;
81 		} integer64;
82 		struct {
83 			u32 items;
84 			u32 item;
85 			char name[64];
86 			u64 names_ptr;
87 			u32 names_length;
88 		} enumerated;
89 		unsigned char reserved[128];
90 	} value;
91 	unsigned char reserved[64];
92 } __attribute__((packed));
93 
94 static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
95 				    struct snd_ctl_elem_info32 __user *data32)
96 {
97 	struct snd_ctl_elem_info *data;
98 	int err;
99 
100 	data = kzalloc(sizeof(*data), GFP_KERNEL);
101 	if (! data)
102 		return -ENOMEM;
103 
104 	err = -EFAULT;
105 	/* copy id */
106 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
107 		goto error;
108 	/* we need to copy the item index.
109 	 * hope this doesn't break anything..
110 	 */
111 	if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
112 		goto error;
113 
114 	snd_power_lock(ctl->card);
115 	err = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
116 	if (err >= 0)
117 		err = snd_ctl_elem_info(ctl, data);
118 	snd_power_unlock(ctl->card);
119 
120 	if (err < 0)
121 		goto error;
122 	/* restore info to 32bit */
123 	err = -EFAULT;
124 	/* id, type, access, count */
125 	if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
126 	    copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
127 		goto error;
128 	if (put_user(data->owner, &data32->owner))
129 		goto error;
130 	switch (data->type) {
131 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
132 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
133 		if (put_user(data->value.integer.min, &data32->value.integer.min) ||
134 		    put_user(data->value.integer.max, &data32->value.integer.max) ||
135 		    put_user(data->value.integer.step, &data32->value.integer.step))
136 			goto error;
137 		break;
138 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
139 		if (copy_to_user(&data32->value.integer64,
140 				 &data->value.integer64,
141 				 sizeof(data->value.integer64)))
142 			goto error;
143 		break;
144 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
145 		if (copy_to_user(&data32->value.enumerated,
146 				 &data->value.enumerated,
147 				 sizeof(data->value.enumerated)))
148 			goto error;
149 		break;
150 	default:
151 		break;
152 	}
153 	err = 0;
154  error:
155 	kfree(data);
156 	return err;
157 }
158 
159 /* read / write */
160 struct snd_ctl_elem_value32 {
161 	struct snd_ctl_elem_id id;
162 	unsigned int indirect;	/* bit-field causes misalignment */
163         union {
164 		s32 integer[128];
165 		unsigned char data[512];
166 #ifndef CONFIG_X86_64
167 		s64 integer64[64];
168 #endif
169         } value;
170         unsigned char reserved[128];
171 };
172 
173 #ifdef CONFIG_X86_X32
174 /* x32 has a different alignment for 64bit values from ia32 */
175 struct snd_ctl_elem_value_x32 {
176 	struct snd_ctl_elem_id id;
177 	unsigned int indirect;	/* bit-field causes misalignment */
178 	union {
179 		s32 integer[128];
180 		unsigned char data[512];
181 		s64 integer64[64];
182 	} value;
183 	unsigned char reserved[128];
184 };
185 #endif /* CONFIG_X86_X32 */
186 
187 /* get the value type and count of the control */
188 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
189 			int *countp)
190 {
191 	struct snd_kcontrol *kctl;
192 	struct snd_ctl_elem_info *info;
193 	int err;
194 
195 	down_read(&card->controls_rwsem);
196 	kctl = snd_ctl_find_id(card, id);
197 	if (! kctl) {
198 		up_read(&card->controls_rwsem);
199 		return -ENOENT;
200 	}
201 	info = kzalloc(sizeof(*info), GFP_KERNEL);
202 	if (info == NULL) {
203 		up_read(&card->controls_rwsem);
204 		return -ENOMEM;
205 	}
206 	info->id = *id;
207 	err = kctl->info(kctl, info);
208 	up_read(&card->controls_rwsem);
209 	if (err >= 0) {
210 		err = info->type;
211 		*countp = info->count;
212 	}
213 	kfree(info);
214 	return err;
215 }
216 
217 static int get_elem_size(int type, int count)
218 {
219 	switch (type) {
220 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
221 		return sizeof(s64) * count;
222 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
223 		return sizeof(int) * count;
224 	case SNDRV_CTL_ELEM_TYPE_BYTES:
225 		return 512;
226 	case SNDRV_CTL_ELEM_TYPE_IEC958:
227 		return sizeof(struct snd_aes_iec958);
228 	default:
229 		return -1;
230 	}
231 }
232 
233 static int copy_ctl_value_from_user(struct snd_card *card,
234 				    struct snd_ctl_elem_value *data,
235 				    void __user *userdata,
236 				    void __user *valuep,
237 				    int *typep, int *countp)
238 {
239 	struct snd_ctl_elem_value32 __user *data32 = userdata;
240 	int i, type, size;
241 	int uninitialized_var(count);
242 	unsigned int indirect;
243 
244 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
245 		return -EFAULT;
246 	if (get_user(indirect, &data32->indirect))
247 		return -EFAULT;
248 	if (indirect)
249 		return -EINVAL;
250 	type = get_ctl_type(card, &data->id, &count);
251 	if (type < 0)
252 		return type;
253 
254 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
255 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
256 		for (i = 0; i < count; i++) {
257 			s32 __user *intp = valuep;
258 			int val;
259 			if (get_user(val, &intp[i]))
260 				return -EFAULT;
261 			data->value.integer.value[i] = val;
262 		}
263 	} else {
264 		size = get_elem_size(type, count);
265 		if (size < 0) {
266 			dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
267 			return -EINVAL;
268 		}
269 		if (copy_from_user(data->value.bytes.data, valuep, size))
270 			return -EFAULT;
271 	}
272 
273 	*typep = type;
274 	*countp = count;
275 	return 0;
276 }
277 
278 /* restore the value to 32bit */
279 static int copy_ctl_value_to_user(void __user *userdata,
280 				  void __user *valuep,
281 				  struct snd_ctl_elem_value *data,
282 				  int type, int count)
283 {
284 	int i, size;
285 
286 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
287 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
288 		for (i = 0; i < count; i++) {
289 			s32 __user *intp = valuep;
290 			int val;
291 			val = data->value.integer.value[i];
292 			if (put_user(val, &intp[i]))
293 				return -EFAULT;
294 		}
295 	} else {
296 		size = get_elem_size(type, count);
297 		if (copy_to_user(valuep, data->value.bytes.data, size))
298 			return -EFAULT;
299 	}
300 	return 0;
301 }
302 
303 static int ctl_elem_read_user(struct snd_card *card,
304 			      void __user *userdata, void __user *valuep)
305 {
306 	struct snd_ctl_elem_value *data;
307 	int err, type, count;
308 
309 	data = kzalloc(sizeof(*data), GFP_KERNEL);
310 	if (data == NULL)
311 		return -ENOMEM;
312 
313 	err = copy_ctl_value_from_user(card, data, userdata, valuep,
314 				       &type, &count);
315 	if (err < 0)
316 		goto error;
317 
318 	snd_power_lock(card);
319 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
320 	if (err >= 0)
321 		err = snd_ctl_elem_read(card, data);
322 	snd_power_unlock(card);
323 	if (err >= 0)
324 		err = copy_ctl_value_to_user(userdata, valuep, data,
325 					     type, count);
326  error:
327 	kfree(data);
328 	return err;
329 }
330 
331 static int ctl_elem_write_user(struct snd_ctl_file *file,
332 			       void __user *userdata, void __user *valuep)
333 {
334 	struct snd_ctl_elem_value *data;
335 	struct snd_card *card = file->card;
336 	int err, type, count;
337 
338 	data = kzalloc(sizeof(*data), GFP_KERNEL);
339 	if (data == NULL)
340 		return -ENOMEM;
341 
342 	err = copy_ctl_value_from_user(card, data, userdata, valuep,
343 				       &type, &count);
344 	if (err < 0)
345 		goto error;
346 
347 	snd_power_lock(card);
348 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
349 	if (err >= 0)
350 		err = snd_ctl_elem_write(card, file, data);
351 	snd_power_unlock(card);
352 	if (err >= 0)
353 		err = copy_ctl_value_to_user(userdata, valuep, data,
354 					     type, count);
355  error:
356 	kfree(data);
357 	return err;
358 }
359 
360 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
361 					 struct snd_ctl_elem_value32 __user *data32)
362 {
363 	return ctl_elem_read_user(card, data32, &data32->value);
364 }
365 
366 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
367 					  struct snd_ctl_elem_value32 __user *data32)
368 {
369 	return ctl_elem_write_user(file, data32, &data32->value);
370 }
371 
372 #ifdef CONFIG_X86_X32
373 static int snd_ctl_elem_read_user_x32(struct snd_card *card,
374 				      struct snd_ctl_elem_value_x32 __user *data32)
375 {
376 	return ctl_elem_read_user(card, data32, &data32->value);
377 }
378 
379 static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
380 				       struct snd_ctl_elem_value_x32 __user *data32)
381 {
382 	return ctl_elem_write_user(file, data32, &data32->value);
383 }
384 #endif /* CONFIG_X86_X32 */
385 
386 /* add or replace a user control */
387 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
388 				   struct snd_ctl_elem_info32 __user *data32,
389 				   int replace)
390 {
391 	struct snd_ctl_elem_info *data;
392 	int err;
393 
394 	data = kzalloc(sizeof(*data), GFP_KERNEL);
395 	if (! data)
396 		return -ENOMEM;
397 
398 	err = -EFAULT;
399 	/* id, type, access, count */ \
400 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
401 	    copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
402 		goto error;
403 	if (get_user(data->owner, &data32->owner) ||
404 	    get_user(data->type, &data32->type))
405 		goto error;
406 	switch (data->type) {
407 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
408 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
409 		if (get_user(data->value.integer.min, &data32->value.integer.min) ||
410 		    get_user(data->value.integer.max, &data32->value.integer.max) ||
411 		    get_user(data->value.integer.step, &data32->value.integer.step))
412 			goto error;
413 		break;
414 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
415 		if (copy_from_user(&data->value.integer64,
416 				   &data32->value.integer64,
417 				   sizeof(data->value.integer64)))
418 			goto error;
419 		break;
420 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
421 		if (copy_from_user(&data->value.enumerated,
422 				   &data32->value.enumerated,
423 				   sizeof(data->value.enumerated)))
424 			goto error;
425 		data->value.enumerated.names_ptr =
426 			(uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
427 		break;
428 	default:
429 		break;
430 	}
431 	err = snd_ctl_elem_add(file, data, replace);
432  error:
433 	kfree(data);
434 	return err;
435 }
436 
437 enum {
438 	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
439 	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
440 	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
441 	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
442 	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
443 	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
444 #ifdef CONFIG_X86_X32
445 	SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
446 	SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
447 #endif /* CONFIG_X86_X32 */
448 };
449 
450 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
451 {
452 	struct snd_ctl_file *ctl;
453 	struct snd_kctl_ioctl *p;
454 	void __user *argp = compat_ptr(arg);
455 	int err;
456 
457 	ctl = file->private_data;
458 	if (snd_BUG_ON(!ctl || !ctl->card))
459 		return -ENXIO;
460 
461 	switch (cmd) {
462 	case SNDRV_CTL_IOCTL_PVERSION:
463 	case SNDRV_CTL_IOCTL_CARD_INFO:
464 	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
465 	case SNDRV_CTL_IOCTL_POWER:
466 	case SNDRV_CTL_IOCTL_POWER_STATE:
467 	case SNDRV_CTL_IOCTL_ELEM_LOCK:
468 	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
469 	case SNDRV_CTL_IOCTL_ELEM_REMOVE:
470 	case SNDRV_CTL_IOCTL_TLV_READ:
471 	case SNDRV_CTL_IOCTL_TLV_WRITE:
472 	case SNDRV_CTL_IOCTL_TLV_COMMAND:
473 		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
474 	case SNDRV_CTL_IOCTL_ELEM_LIST32:
475 		return snd_ctl_elem_list_compat(ctl->card, argp);
476 	case SNDRV_CTL_IOCTL_ELEM_INFO32:
477 		return snd_ctl_elem_info_compat(ctl, argp);
478 	case SNDRV_CTL_IOCTL_ELEM_READ32:
479 		return snd_ctl_elem_read_user_compat(ctl->card, argp);
480 	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
481 		return snd_ctl_elem_write_user_compat(ctl, argp);
482 	case SNDRV_CTL_IOCTL_ELEM_ADD32:
483 		return snd_ctl_elem_add_compat(ctl, argp, 0);
484 	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
485 		return snd_ctl_elem_add_compat(ctl, argp, 1);
486 #ifdef CONFIG_X86_X32
487 	case SNDRV_CTL_IOCTL_ELEM_READ_X32:
488 		return snd_ctl_elem_read_user_x32(ctl->card, argp);
489 	case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
490 		return snd_ctl_elem_write_user_x32(ctl, argp);
491 #endif /* CONFIG_X86_X32 */
492 	}
493 
494 	down_read(&snd_ioctl_rwsem);
495 	list_for_each_entry(p, &snd_control_compat_ioctls, list) {
496 		if (p->fioctl) {
497 			err = p->fioctl(ctl->card, ctl, cmd, arg);
498 			if (err != -ENOIOCTLCMD) {
499 				up_read(&snd_ioctl_rwsem);
500 				return err;
501 			}
502 		}
503 	}
504 	up_read(&snd_ioctl_rwsem);
505 	return -ENOIOCTLCMD;
506 }
507