xref: /openbmc/linux/sound/core/control_compat.c (revision 6d99a79c)
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 	err = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
115 	if (err < 0)
116 		goto error;
117 	err = snd_ctl_elem_info(ctl, data);
118 	if (err < 0)
119 		goto error;
120 	/* restore info to 32bit */
121 	err = -EFAULT;
122 	/* id, type, access, count */
123 	if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
124 	    copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
125 		goto error;
126 	if (put_user(data->owner, &data32->owner))
127 		goto error;
128 	switch (data->type) {
129 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
130 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
131 		if (put_user(data->value.integer.min, &data32->value.integer.min) ||
132 		    put_user(data->value.integer.max, &data32->value.integer.max) ||
133 		    put_user(data->value.integer.step, &data32->value.integer.step))
134 			goto error;
135 		break;
136 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
137 		if (copy_to_user(&data32->value.integer64,
138 				 &data->value.integer64,
139 				 sizeof(data->value.integer64)))
140 			goto error;
141 		break;
142 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
143 		if (copy_to_user(&data32->value.enumerated,
144 				 &data->value.enumerated,
145 				 sizeof(data->value.enumerated)))
146 			goto error;
147 		break;
148 	default:
149 		break;
150 	}
151 	err = 0;
152  error:
153 	kfree(data);
154 	return err;
155 }
156 
157 /* read / write */
158 struct snd_ctl_elem_value32 {
159 	struct snd_ctl_elem_id id;
160 	unsigned int indirect;	/* bit-field causes misalignment */
161         union {
162 		s32 integer[128];
163 		unsigned char data[512];
164 #ifndef CONFIG_X86_64
165 		s64 integer64[64];
166 #endif
167         } value;
168         unsigned char reserved[128];
169 };
170 
171 #ifdef CONFIG_X86_X32
172 /* x32 has a different alignment for 64bit values from ia32 */
173 struct snd_ctl_elem_value_x32 {
174 	struct snd_ctl_elem_id id;
175 	unsigned int indirect;	/* bit-field causes misalignment */
176 	union {
177 		s32 integer[128];
178 		unsigned char data[512];
179 		s64 integer64[64];
180 	} value;
181 	unsigned char reserved[128];
182 };
183 #endif /* CONFIG_X86_X32 */
184 
185 /* get the value type and count of the control */
186 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
187 			int *countp)
188 {
189 	struct snd_kcontrol *kctl;
190 	struct snd_ctl_elem_info *info;
191 	int err;
192 
193 	down_read(&card->controls_rwsem);
194 	kctl = snd_ctl_find_id(card, id);
195 	if (! kctl) {
196 		up_read(&card->controls_rwsem);
197 		return -ENOENT;
198 	}
199 	info = kzalloc(sizeof(*info), GFP_KERNEL);
200 	if (info == NULL) {
201 		up_read(&card->controls_rwsem);
202 		return -ENOMEM;
203 	}
204 	info->id = *id;
205 	err = kctl->info(kctl, info);
206 	up_read(&card->controls_rwsem);
207 	if (err >= 0) {
208 		err = info->type;
209 		*countp = info->count;
210 	}
211 	kfree(info);
212 	return err;
213 }
214 
215 static int get_elem_size(int type, int count)
216 {
217 	switch (type) {
218 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
219 		return sizeof(s64) * count;
220 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
221 		return sizeof(int) * count;
222 	case SNDRV_CTL_ELEM_TYPE_BYTES:
223 		return 512;
224 	case SNDRV_CTL_ELEM_TYPE_IEC958:
225 		return sizeof(struct snd_aes_iec958);
226 	default:
227 		return -1;
228 	}
229 }
230 
231 static int copy_ctl_value_from_user(struct snd_card *card,
232 				    struct snd_ctl_elem_value *data,
233 				    void __user *userdata,
234 				    void __user *valuep,
235 				    int *typep, int *countp)
236 {
237 	struct snd_ctl_elem_value32 __user *data32 = userdata;
238 	int i, type, size;
239 	int uninitialized_var(count);
240 	unsigned int indirect;
241 
242 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
243 		return -EFAULT;
244 	if (get_user(indirect, &data32->indirect))
245 		return -EFAULT;
246 	if (indirect)
247 		return -EINVAL;
248 	type = get_ctl_type(card, &data->id, &count);
249 	if (type < 0)
250 		return type;
251 
252 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
253 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
254 		for (i = 0; i < count; i++) {
255 			s32 __user *intp = valuep;
256 			int val;
257 			if (get_user(val, &intp[i]))
258 				return -EFAULT;
259 			data->value.integer.value[i] = val;
260 		}
261 	} else {
262 		size = get_elem_size(type, count);
263 		if (size < 0) {
264 			dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
265 			return -EINVAL;
266 		}
267 		if (copy_from_user(data->value.bytes.data, valuep, size))
268 			return -EFAULT;
269 	}
270 
271 	*typep = type;
272 	*countp = count;
273 	return 0;
274 }
275 
276 /* restore the value to 32bit */
277 static int copy_ctl_value_to_user(void __user *userdata,
278 				  void __user *valuep,
279 				  struct snd_ctl_elem_value *data,
280 				  int type, int count)
281 {
282 	int i, size;
283 
284 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
285 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
286 		for (i = 0; i < count; i++) {
287 			s32 __user *intp = valuep;
288 			int val;
289 			val = data->value.integer.value[i];
290 			if (put_user(val, &intp[i]))
291 				return -EFAULT;
292 		}
293 	} else {
294 		size = get_elem_size(type, count);
295 		if (copy_to_user(valuep, data->value.bytes.data, size))
296 			return -EFAULT;
297 	}
298 	return 0;
299 }
300 
301 static int ctl_elem_read_user(struct snd_card *card,
302 			      void __user *userdata, void __user *valuep)
303 {
304 	struct snd_ctl_elem_value *data;
305 	int err, type, count;
306 
307 	data = kzalloc(sizeof(*data), GFP_KERNEL);
308 	if (data == NULL)
309 		return -ENOMEM;
310 
311 	err = copy_ctl_value_from_user(card, data, userdata, valuep,
312 				       &type, &count);
313 	if (err < 0)
314 		goto error;
315 
316 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
317 	if (err < 0)
318 		goto error;
319 	err = snd_ctl_elem_read(card, data);
320 	if (err < 0)
321 		goto error;
322 	err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
323  error:
324 	kfree(data);
325 	return err;
326 }
327 
328 static int ctl_elem_write_user(struct snd_ctl_file *file,
329 			       void __user *userdata, void __user *valuep)
330 {
331 	struct snd_ctl_elem_value *data;
332 	struct snd_card *card = file->card;
333 	int err, type, count;
334 
335 	data = kzalloc(sizeof(*data), GFP_KERNEL);
336 	if (data == NULL)
337 		return -ENOMEM;
338 
339 	err = copy_ctl_value_from_user(card, data, userdata, valuep,
340 				       &type, &count);
341 	if (err < 0)
342 		goto error;
343 
344 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
345 	if (err < 0)
346 		goto error;
347 	err = snd_ctl_elem_write(card, file, data);
348 	if (err < 0)
349 		goto error;
350 	err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
351  error:
352 	kfree(data);
353 	return err;
354 }
355 
356 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
357 					 struct snd_ctl_elem_value32 __user *data32)
358 {
359 	return ctl_elem_read_user(card, data32, &data32->value);
360 }
361 
362 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
363 					  struct snd_ctl_elem_value32 __user *data32)
364 {
365 	return ctl_elem_write_user(file, data32, &data32->value);
366 }
367 
368 #ifdef CONFIG_X86_X32
369 static int snd_ctl_elem_read_user_x32(struct snd_card *card,
370 				      struct snd_ctl_elem_value_x32 __user *data32)
371 {
372 	return ctl_elem_read_user(card, data32, &data32->value);
373 }
374 
375 static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
376 				       struct snd_ctl_elem_value_x32 __user *data32)
377 {
378 	return ctl_elem_write_user(file, data32, &data32->value);
379 }
380 #endif /* CONFIG_X86_X32 */
381 
382 /* add or replace a user control */
383 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
384 				   struct snd_ctl_elem_info32 __user *data32,
385 				   int replace)
386 {
387 	struct snd_ctl_elem_info *data;
388 	int err;
389 
390 	data = kzalloc(sizeof(*data), GFP_KERNEL);
391 	if (! data)
392 		return -ENOMEM;
393 
394 	err = -EFAULT;
395 	/* id, type, access, count */ \
396 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
397 	    copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
398 		goto error;
399 	if (get_user(data->owner, &data32->owner))
400 		goto error;
401 	switch (data->type) {
402 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
403 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
404 		if (get_user(data->value.integer.min, &data32->value.integer.min) ||
405 		    get_user(data->value.integer.max, &data32->value.integer.max) ||
406 		    get_user(data->value.integer.step, &data32->value.integer.step))
407 			goto error;
408 		break;
409 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
410 		if (copy_from_user(&data->value.integer64,
411 				   &data32->value.integer64,
412 				   sizeof(data->value.integer64)))
413 			goto error;
414 		break;
415 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
416 		if (copy_from_user(&data->value.enumerated,
417 				   &data32->value.enumerated,
418 				   sizeof(data->value.enumerated)))
419 			goto error;
420 		data->value.enumerated.names_ptr =
421 			(uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
422 		break;
423 	default:
424 		break;
425 	}
426 	err = snd_ctl_elem_add(file, data, replace);
427  error:
428 	kfree(data);
429 	return err;
430 }
431 
432 enum {
433 	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
434 	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
435 	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
436 	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
437 	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
438 	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
439 #ifdef CONFIG_X86_X32
440 	SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
441 	SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
442 #endif /* CONFIG_X86_X32 */
443 };
444 
445 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
446 {
447 	struct snd_ctl_file *ctl;
448 	struct snd_kctl_ioctl *p;
449 	void __user *argp = compat_ptr(arg);
450 	int err;
451 
452 	ctl = file->private_data;
453 	if (snd_BUG_ON(!ctl || !ctl->card))
454 		return -ENXIO;
455 
456 	switch (cmd) {
457 	case SNDRV_CTL_IOCTL_PVERSION:
458 	case SNDRV_CTL_IOCTL_CARD_INFO:
459 	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
460 	case SNDRV_CTL_IOCTL_POWER:
461 	case SNDRV_CTL_IOCTL_POWER_STATE:
462 	case SNDRV_CTL_IOCTL_ELEM_LOCK:
463 	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
464 	case SNDRV_CTL_IOCTL_ELEM_REMOVE:
465 	case SNDRV_CTL_IOCTL_TLV_READ:
466 	case SNDRV_CTL_IOCTL_TLV_WRITE:
467 	case SNDRV_CTL_IOCTL_TLV_COMMAND:
468 		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
469 	case SNDRV_CTL_IOCTL_ELEM_LIST32:
470 		return snd_ctl_elem_list_compat(ctl->card, argp);
471 	case SNDRV_CTL_IOCTL_ELEM_INFO32:
472 		return snd_ctl_elem_info_compat(ctl, argp);
473 	case SNDRV_CTL_IOCTL_ELEM_READ32:
474 		return snd_ctl_elem_read_user_compat(ctl->card, argp);
475 	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
476 		return snd_ctl_elem_write_user_compat(ctl, argp);
477 	case SNDRV_CTL_IOCTL_ELEM_ADD32:
478 		return snd_ctl_elem_add_compat(ctl, argp, 0);
479 	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
480 		return snd_ctl_elem_add_compat(ctl, argp, 1);
481 #ifdef CONFIG_X86_X32
482 	case SNDRV_CTL_IOCTL_ELEM_READ_X32:
483 		return snd_ctl_elem_read_user_x32(ctl->card, argp);
484 	case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
485 		return snd_ctl_elem_write_user_x32(ctl, argp);
486 #endif /* CONFIG_X86_X32 */
487 	}
488 
489 	down_read(&snd_ioctl_rwsem);
490 	list_for_each_entry(p, &snd_control_compat_ioctls, list) {
491 		if (p->fioctl) {
492 			err = p->fioctl(ctl->card, ctl, cmd, arg);
493 			if (err != -ENOIOCTLCMD) {
494 				up_read(&snd_ioctl_rwsem);
495 				return err;
496 			}
497 		}
498 	}
499 	up_read(&snd_ioctl_rwsem);
500 	return -ENOIOCTLCMD;
501 }
502