xref: /openbmc/linux/sound/core/control_compat.c (revision 206a81c1)
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 
174 /* get the value type and count of the control */
175 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
176 			int *countp)
177 {
178 	struct snd_kcontrol *kctl;
179 	struct snd_ctl_elem_info *info;
180 	int err;
181 
182 	down_read(&card->controls_rwsem);
183 	kctl = snd_ctl_find_id(card, id);
184 	if (! kctl) {
185 		up_read(&card->controls_rwsem);
186 		return -ENXIO;
187 	}
188 	info = kzalloc(sizeof(*info), GFP_KERNEL);
189 	if (info == NULL) {
190 		up_read(&card->controls_rwsem);
191 		return -ENOMEM;
192 	}
193 	info->id = *id;
194 	err = kctl->info(kctl, info);
195 	up_read(&card->controls_rwsem);
196 	if (err >= 0) {
197 		err = info->type;
198 		*countp = info->count;
199 	}
200 	kfree(info);
201 	return err;
202 }
203 
204 static int get_elem_size(int type, int count)
205 {
206 	switch (type) {
207 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
208 		return sizeof(s64) * count;
209 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
210 		return sizeof(int) * count;
211 	case SNDRV_CTL_ELEM_TYPE_BYTES:
212 		return 512;
213 	case SNDRV_CTL_ELEM_TYPE_IEC958:
214 		return sizeof(struct snd_aes_iec958);
215 	default:
216 		return -1;
217 	}
218 }
219 
220 static int copy_ctl_value_from_user(struct snd_card *card,
221 				    struct snd_ctl_elem_value *data,
222 				    struct snd_ctl_elem_value32 __user *data32,
223 				    int *typep, int *countp)
224 {
225 	int i, type, size;
226 	int uninitialized_var(count);
227 	unsigned int indirect;
228 
229 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
230 		return -EFAULT;
231 	if (get_user(indirect, &data32->indirect))
232 		return -EFAULT;
233 	if (indirect)
234 		return -EINVAL;
235 	type = get_ctl_type(card, &data->id, &count);
236 	if (type < 0)
237 		return type;
238 
239 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
240 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
241 		for (i = 0; i < count; i++) {
242 			int val;
243 			if (get_user(val, &data32->value.integer[i]))
244 				return -EFAULT;
245 			data->value.integer.value[i] = val;
246 		}
247 	} else {
248 		size = get_elem_size(type, count);
249 		if (size < 0) {
250 			dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
251 			return -EINVAL;
252 		}
253 		if (copy_from_user(data->value.bytes.data,
254 				   data32->value.data, size))
255 			return -EFAULT;
256 	}
257 
258 	*typep = type;
259 	*countp = count;
260 	return 0;
261 }
262 
263 /* restore the value to 32bit */
264 static int copy_ctl_value_to_user(struct snd_ctl_elem_value32 __user *data32,
265 				  struct snd_ctl_elem_value *data,
266 				  int type, int count)
267 {
268 	int i, size;
269 
270 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
271 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
272 		for (i = 0; i < count; i++) {
273 			int val;
274 			val = data->value.integer.value[i];
275 			if (put_user(val, &data32->value.integer[i]))
276 				return -EFAULT;
277 		}
278 	} else {
279 		size = get_elem_size(type, count);
280 		if (copy_to_user(data32->value.data,
281 				 data->value.bytes.data, size))
282 			return -EFAULT;
283 	}
284 	return 0;
285 }
286 
287 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
288 					 struct snd_ctl_elem_value32 __user *data32)
289 {
290 	struct snd_ctl_elem_value *data;
291 	int err, type, count;
292 
293 	data = kzalloc(sizeof(*data), GFP_KERNEL);
294 	if (data == NULL)
295 		return -ENOMEM;
296 
297 	if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
298 		goto error;
299 
300 	snd_power_lock(card);
301 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
302 	if (err >= 0)
303 		err = snd_ctl_elem_read(card, data);
304 	snd_power_unlock(card);
305 	if (err >= 0)
306 		err = copy_ctl_value_to_user(data32, data, type, count);
307  error:
308 	kfree(data);
309 	return err;
310 }
311 
312 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
313 					  struct snd_ctl_elem_value32 __user *data32)
314 {
315 	struct snd_ctl_elem_value *data;
316 	struct snd_card *card = file->card;
317 	int err, type, count;
318 
319 	data = kzalloc(sizeof(*data), GFP_KERNEL);
320 	if (data == NULL)
321 		return -ENOMEM;
322 
323 	if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
324 		goto error;
325 
326 	snd_power_lock(card);
327 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
328 	if (err >= 0)
329 		err = snd_ctl_elem_write(card, file, data);
330 	snd_power_unlock(card);
331 	if (err >= 0)
332 		err = copy_ctl_value_to_user(data32, data, type, count);
333  error:
334 	kfree(data);
335 	return err;
336 }
337 
338 /* add or replace a user control */
339 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
340 				   struct snd_ctl_elem_info32 __user *data32,
341 				   int replace)
342 {
343 	struct snd_ctl_elem_info *data;
344 	int err;
345 
346 	data = kzalloc(sizeof(*data), GFP_KERNEL);
347 	if (! data)
348 		return -ENOMEM;
349 
350 	err = -EFAULT;
351 	/* id, type, access, count */ \
352 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
353 	    copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
354 		goto error;
355 	if (get_user(data->owner, &data32->owner) ||
356 	    get_user(data->type, &data32->type))
357 		goto error;
358 	switch (data->type) {
359 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
360 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
361 		if (get_user(data->value.integer.min, &data32->value.integer.min) ||
362 		    get_user(data->value.integer.max, &data32->value.integer.max) ||
363 		    get_user(data->value.integer.step, &data32->value.integer.step))
364 			goto error;
365 		break;
366 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
367 		if (copy_from_user(&data->value.integer64,
368 				   &data32->value.integer64,
369 				   sizeof(data->value.integer64)))
370 			goto error;
371 		break;
372 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
373 		if (copy_from_user(&data->value.enumerated,
374 				   &data32->value.enumerated,
375 				   sizeof(data->value.enumerated)))
376 			goto error;
377 		data->value.enumerated.names_ptr =
378 			(uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
379 		break;
380 	default:
381 		break;
382 	}
383 	err = snd_ctl_elem_add(file, data, replace);
384  error:
385 	kfree(data);
386 	return err;
387 }
388 
389 enum {
390 	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
391 	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
392 	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
393 	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
394 	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
395 	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
396 };
397 
398 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
399 {
400 	struct snd_ctl_file *ctl;
401 	struct snd_kctl_ioctl *p;
402 	void __user *argp = compat_ptr(arg);
403 	int err;
404 
405 	ctl = file->private_data;
406 	if (snd_BUG_ON(!ctl || !ctl->card))
407 		return -ENXIO;
408 
409 	switch (cmd) {
410 	case SNDRV_CTL_IOCTL_PVERSION:
411 	case SNDRV_CTL_IOCTL_CARD_INFO:
412 	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
413 	case SNDRV_CTL_IOCTL_POWER:
414 	case SNDRV_CTL_IOCTL_POWER_STATE:
415 	case SNDRV_CTL_IOCTL_ELEM_LOCK:
416 	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
417 	case SNDRV_CTL_IOCTL_ELEM_REMOVE:
418 	case SNDRV_CTL_IOCTL_TLV_READ:
419 	case SNDRV_CTL_IOCTL_TLV_WRITE:
420 	case SNDRV_CTL_IOCTL_TLV_COMMAND:
421 		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
422 	case SNDRV_CTL_IOCTL_ELEM_LIST32:
423 		return snd_ctl_elem_list_compat(ctl->card, argp);
424 	case SNDRV_CTL_IOCTL_ELEM_INFO32:
425 		return snd_ctl_elem_info_compat(ctl, argp);
426 	case SNDRV_CTL_IOCTL_ELEM_READ32:
427 		return snd_ctl_elem_read_user_compat(ctl->card, argp);
428 	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
429 		return snd_ctl_elem_write_user_compat(ctl, argp);
430 	case SNDRV_CTL_IOCTL_ELEM_ADD32:
431 		return snd_ctl_elem_add_compat(ctl, argp, 0);
432 	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
433 		return snd_ctl_elem_add_compat(ctl, argp, 1);
434 	}
435 
436 	down_read(&snd_ioctl_rwsem);
437 	list_for_each_entry(p, &snd_control_compat_ioctls, list) {
438 		if (p->fioctl) {
439 			err = p->fioctl(ctl->card, ctl, cmd, arg);
440 			if (err != -ENOIOCTLCMD) {
441 				up_read(&snd_ioctl_rwsem);
442 				return err;
443 			}
444 		}
445 	}
446 	up_read(&snd_ioctl_rwsem);
447 	return -ENOIOCTLCMD;
448 }
449