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 
snd_ctl_elem_list_compat(struct snd_card * card,struct snd_ctl_elem_list32 __user * data32)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 		} enumerated;
87 		unsigned char reserved[128];
88 	} value;
89 	unsigned char reserved[64];
90 } __attribute__((packed));
91 
snd_ctl_elem_info_compat(struct snd_ctl_file * ctl,struct snd_ctl_elem_info32 __user * data32)92 static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
93 				    struct snd_ctl_elem_info32 __user *data32)
94 {
95 	struct snd_ctl_elem_info *data;
96 	int err;
97 
98 	data = kzalloc(sizeof(*data), GFP_KERNEL);
99 	if (! data)
100 		return -ENOMEM;
101 
102 	err = -EFAULT;
103 	/* copy id */
104 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
105 		goto error;
106 	/* we need to copy the item index.
107 	 * hope this doesn't break anything..
108 	 */
109 	if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
110 		goto error;
111 
112 	snd_power_lock(ctl->card);
113 	err = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
114 	if (err >= 0)
115 		err = snd_ctl_elem_info(ctl, data);
116 	snd_power_unlock(ctl->card);
117 
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 
172 /* get the value type and count of the control */
get_ctl_type(struct snd_card * card,struct snd_ctl_elem_id * id,int * countp)173 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
174 			int *countp)
175 {
176 	struct snd_kcontrol *kctl;
177 	struct snd_ctl_elem_info *info;
178 	int err;
179 
180 	down_read(&card->controls_rwsem);
181 	kctl = snd_ctl_find_id(card, id);
182 	if (! kctl) {
183 		up_read(&card->controls_rwsem);
184 		return -ENXIO;
185 	}
186 	info = kzalloc(sizeof(*info), GFP_KERNEL);
187 	if (info == NULL) {
188 		up_read(&card->controls_rwsem);
189 		return -ENOMEM;
190 	}
191 	info->id = *id;
192 	err = kctl->info(kctl, info);
193 	up_read(&card->controls_rwsem);
194 	if (err >= 0) {
195 		err = info->type;
196 		*countp = info->count;
197 	}
198 	kfree(info);
199 	return err;
200 }
201 
get_elem_size(int type,int count)202 static int get_elem_size(int type, int count)
203 {
204 	switch (type) {
205 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
206 		return sizeof(s64) * count;
207 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
208 		return sizeof(int) * count;
209 	case SNDRV_CTL_ELEM_TYPE_BYTES:
210 		return 512;
211 	case SNDRV_CTL_ELEM_TYPE_IEC958:
212 		return sizeof(struct snd_aes_iec958);
213 	default:
214 		return -1;
215 	}
216 }
217 
copy_ctl_value_from_user(struct snd_card * card,struct snd_ctl_elem_value * data,struct snd_ctl_elem_value32 __user * data32,int * typep,int * countp)218 static int copy_ctl_value_from_user(struct snd_card *card,
219 				    struct snd_ctl_elem_value *data,
220 				    struct snd_ctl_elem_value32 __user *data32,
221 				    int *typep, int *countp)
222 {
223 	int i, type, size;
224 	int uninitialized_var(count);
225 	unsigned int indirect;
226 
227 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
228 		return -EFAULT;
229 	if (get_user(indirect, &data32->indirect))
230 		return -EFAULT;
231 	if (indirect)
232 		return -EINVAL;
233 	type = get_ctl_type(card, &data->id, &count);
234 	if (type < 0)
235 		return type;
236 
237 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
238 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
239 		for (i = 0; i < count; i++) {
240 			int val;
241 			if (get_user(val, &data32->value.integer[i]))
242 				return -EFAULT;
243 			data->value.integer.value[i] = val;
244 		}
245 	} else {
246 		size = get_elem_size(type, count);
247 		if (size < 0) {
248 			printk(KERN_ERR "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
249 			return -EINVAL;
250 		}
251 		if (copy_from_user(data->value.bytes.data,
252 				   data32->value.data, size))
253 			return -EFAULT;
254 	}
255 
256 	*typep = type;
257 	*countp = count;
258 	return 0;
259 }
260 
261 /* restore the value to 32bit */
copy_ctl_value_to_user(struct snd_ctl_elem_value32 __user * data32,struct snd_ctl_elem_value * data,int type,int count)262 static int copy_ctl_value_to_user(struct snd_ctl_elem_value32 __user *data32,
263 				  struct snd_ctl_elem_value *data,
264 				  int type, int count)
265 {
266 	int i, size;
267 
268 	if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
269 	    type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
270 		for (i = 0; i < count; i++) {
271 			int val;
272 			val = data->value.integer.value[i];
273 			if (put_user(val, &data32->value.integer[i]))
274 				return -EFAULT;
275 		}
276 	} else {
277 		size = get_elem_size(type, count);
278 		if (copy_to_user(data32->value.data,
279 				 data->value.bytes.data, size))
280 			return -EFAULT;
281 	}
282 	return 0;
283 }
284 
snd_ctl_elem_read_user_compat(struct snd_card * card,struct snd_ctl_elem_value32 __user * data32)285 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
286 					 struct snd_ctl_elem_value32 __user *data32)
287 {
288 	struct snd_ctl_elem_value *data;
289 	int err, type, count;
290 
291 	data = kzalloc(sizeof(*data), GFP_KERNEL);
292 	if (data == NULL)
293 		return -ENOMEM;
294 
295 	if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
296 		goto error;
297 
298 	snd_power_lock(card);
299 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
300 	if (err >= 0)
301 		err = snd_ctl_elem_read(card, data);
302 	snd_power_unlock(card);
303 	if (err >= 0)
304 		err = copy_ctl_value_to_user(data32, data, type, count);
305  error:
306 	kfree(data);
307 	return err;
308 }
309 
snd_ctl_elem_write_user_compat(struct snd_ctl_file * file,struct snd_ctl_elem_value32 __user * data32)310 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
311 					  struct snd_ctl_elem_value32 __user *data32)
312 {
313 	struct snd_ctl_elem_value *data;
314 	struct snd_card *card = file->card;
315 	int err, type, count;
316 
317 	data = kzalloc(sizeof(*data), GFP_KERNEL);
318 	if (data == NULL)
319 		return -ENOMEM;
320 
321 	if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
322 		goto error;
323 
324 	snd_power_lock(card);
325 	err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
326 	if (err >= 0)
327 		err = snd_ctl_elem_write(card, file, data);
328 	snd_power_unlock(card);
329 	if (err >= 0)
330 		err = copy_ctl_value_to_user(data32, data, type, count);
331  error:
332 	kfree(data);
333 	return err;
334 }
335 
336 /* add or replace a user control */
snd_ctl_elem_add_compat(struct snd_ctl_file * file,struct snd_ctl_elem_info32 __user * data32,int replace)337 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
338 				   struct snd_ctl_elem_info32 __user *data32,
339 				   int replace)
340 {
341 	struct snd_ctl_elem_info *data;
342 	int err;
343 
344 	data = kzalloc(sizeof(*data), GFP_KERNEL);
345 	if (! data)
346 		return -ENOMEM;
347 
348 	err = -EFAULT;
349 	/* id, type, access, count */ \
350 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
351 	    copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
352 		goto error;
353 	if (get_user(data->owner, &data32->owner) ||
354 	    get_user(data->type, &data32->type))
355 		goto error;
356 	switch (data->type) {
357 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
358 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
359 		if (get_user(data->value.integer.min, &data32->value.integer.min) ||
360 		    get_user(data->value.integer.max, &data32->value.integer.max) ||
361 		    get_user(data->value.integer.step, &data32->value.integer.step))
362 			goto error;
363 		break;
364 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
365 		if (copy_from_user(&data->value.integer64,
366 				   &data32->value.integer64,
367 				   sizeof(data->value.integer64)))
368 			goto error;
369 		break;
370 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
371 		if (copy_from_user(&data->value.enumerated,
372 				   &data32->value.enumerated,
373 				   sizeof(data->value.enumerated)))
374 			goto error;
375 		break;
376 	default:
377 		break;
378 	}
379 	err = snd_ctl_elem_add(file, data, replace);
380  error:
381 	kfree(data);
382 	return err;
383 }
384 
385 enum {
386 	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
387 	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
388 	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
389 	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
390 	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
391 	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
392 };
393 
snd_ctl_ioctl_compat(struct file * file,unsigned int cmd,unsigned long arg)394 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
395 {
396 	struct snd_ctl_file *ctl;
397 	struct snd_kctl_ioctl *p;
398 	void __user *argp = compat_ptr(arg);
399 	int err;
400 
401 	ctl = file->private_data;
402 	if (snd_BUG_ON(!ctl || !ctl->card))
403 		return -ENXIO;
404 
405 	switch (cmd) {
406 	case SNDRV_CTL_IOCTL_PVERSION:
407 	case SNDRV_CTL_IOCTL_CARD_INFO:
408 	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
409 	case SNDRV_CTL_IOCTL_POWER:
410 	case SNDRV_CTL_IOCTL_POWER_STATE:
411 	case SNDRV_CTL_IOCTL_ELEM_LOCK:
412 	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
413 	case SNDRV_CTL_IOCTL_ELEM_REMOVE:
414 	case SNDRV_CTL_IOCTL_TLV_READ:
415 	case SNDRV_CTL_IOCTL_TLV_WRITE:
416 	case SNDRV_CTL_IOCTL_TLV_COMMAND:
417 		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
418 	case SNDRV_CTL_IOCTL_ELEM_LIST32:
419 		return snd_ctl_elem_list_compat(ctl->card, argp);
420 	case SNDRV_CTL_IOCTL_ELEM_INFO32:
421 		return snd_ctl_elem_info_compat(ctl, argp);
422 	case SNDRV_CTL_IOCTL_ELEM_READ32:
423 		return snd_ctl_elem_read_user_compat(ctl->card, argp);
424 	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
425 		return snd_ctl_elem_write_user_compat(ctl, argp);
426 	case SNDRV_CTL_IOCTL_ELEM_ADD32:
427 		return snd_ctl_elem_add_compat(ctl, argp, 0);
428 	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
429 		return snd_ctl_elem_add_compat(ctl, argp, 1);
430 	}
431 
432 	down_read(&snd_ioctl_rwsem);
433 	list_for_each_entry(p, &snd_control_compat_ioctls, list) {
434 		if (p->fioctl) {
435 			err = p->fioctl(ctl->card, ctl, cmd, arg);
436 			if (err != -ENOIOCTLCMD) {
437 				up_read(&snd_ioctl_rwsem);
438 				return err;
439 			}
440 		}
441 	}
442 	up_read(&snd_ioctl_rwsem);
443 	return -ENOIOCTLCMD;
444 }
445