1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * compat ioctls for control API
4 *
5 *   Copyright (c) by Takashi Iwai <tiwai@suse.de>
6 */
7
8/* this file included from control.c */
9
10#include <linux/compat.h>
11#include <linux/slab.h>
12
13struct snd_ctl_elem_list32 {
14	u32 offset;
15	u32 space;
16	u32 used;
17	u32 count;
18	u32 pids;
19	unsigned char reserved[50];
20} /* don't set packed attribute here */;
21
22static int snd_ctl_elem_list_compat(struct snd_card *card,
23				    struct snd_ctl_elem_list32 __user *data32)
24{
25	struct snd_ctl_elem_list data = {};
26	compat_caddr_t ptr;
27	int err;
28
29	/* offset, space, used, count */
30	if (copy_from_user(&data, data32, 4 * sizeof(u32)))
31		return -EFAULT;
32	/* pids */
33	if (get_user(ptr, &data32->pids))
34		return -EFAULT;
35	data.pids = compat_ptr(ptr);
36	err = snd_ctl_elem_list(card, &data);
37	if (err < 0)
38		return err;
39	/* copy the result */
40	if (copy_to_user(data32, &data, 4 * sizeof(u32)))
41		return -EFAULT;
42	return 0;
43}
44
45/*
46 * control element info
47 * it uses union, so the things are not easy..
48 */
49
50struct snd_ctl_elem_info32 {
51	struct snd_ctl_elem_id id; // the size of struct is same
52	s32 type;
53	u32 access;
54	u32 count;
55	s32 owner;
56	union {
57		struct {
58			s32 min;
59			s32 max;
60			s32 step;
61		} integer;
62		struct {
63			u64 min;
64			u64 max;
65			u64 step;
66		} integer64;
67		struct {
68			u32 items;
69			u32 item;
70			char name[64];
71			u64 names_ptr;
72			u32 names_length;
73		} enumerated;
74		unsigned char reserved[128];
75	} value;
76	unsigned char reserved[64];
77} __packed;
78
79static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
80				    struct snd_ctl_elem_info32 __user *data32)
81{
82	struct snd_ctl_elem_info *data __free(kfree) = NULL;
83	int err;
84
85	data = kzalloc(sizeof(*data), GFP_KERNEL);
86	if (! data)
87		return -ENOMEM;
88
89	/* copy id */
90	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
91		return -EFAULT;
92	/* we need to copy the item index.
93	 * hope this doesn't break anything..
94	 */
95	if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
96		return -EFAULT;
97
98	err = snd_ctl_elem_info(ctl, data);
99	if (err < 0)
100		return err;
101	/* restore info to 32bit */
102	/* id, type, access, count */
103	if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
104	    copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
105		return -EFAULT;
106	if (put_user(data->owner, &data32->owner))
107		return -EFAULT;
108	switch (data->type) {
109	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
110	case SNDRV_CTL_ELEM_TYPE_INTEGER:
111		if (put_user(data->value.integer.min, &data32->value.integer.min) ||
112		    put_user(data->value.integer.max, &data32->value.integer.max) ||
113		    put_user(data->value.integer.step, &data32->value.integer.step))
114			return -EFAULT;
115		break;
116	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
117		if (copy_to_user(&data32->value.integer64,
118				 &data->value.integer64,
119				 sizeof(data->value.integer64)))
120			return -EFAULT;
121		break;
122	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
123		if (copy_to_user(&data32->value.enumerated,
124				 &data->value.enumerated,
125				 sizeof(data->value.enumerated)))
126			return -EFAULT;
127		break;
128	default:
129		break;
130	}
131	return 0;
132}
133
134/* read / write */
135struct snd_ctl_elem_value32 {
136	struct snd_ctl_elem_id id;
137	unsigned int indirect;	/* bit-field causes misalignment */
138        union {
139		s32 integer[128];
140		unsigned char data[512];
141#ifndef CONFIG_X86_64
142		s64 integer64[64];
143#endif
144        } value;
145        unsigned char reserved[128];
146};
147
148#ifdef CONFIG_X86_X32_ABI
149/* x32 has a different alignment for 64bit values from ia32 */
150struct snd_ctl_elem_value_x32 {
151	struct snd_ctl_elem_id id;
152	unsigned int indirect;	/* bit-field causes misalignment */
153	union {
154		s32 integer[128];
155		unsigned char data[512];
156		s64 integer64[64];
157	} value;
158	unsigned char reserved[128];
159};
160#endif /* CONFIG_X86_X32_ABI */
161
162/* get the value type and count of the control */
163static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
164			int *countp)
165{
166	struct snd_kcontrol *kctl;
167	struct snd_ctl_elem_info *info __free(kfree) = NULL;
168	int err;
169
170	guard(rwsem_read)(&card->controls_rwsem);
171	kctl = snd_ctl_find_id_locked(card, id);
172	if (!kctl)
173		return -ENOENT;
174	info = kzalloc(sizeof(*info), GFP_KERNEL);
175	if (info == NULL)
176		return -ENOMEM;
177	info->id = *id;
178	err = snd_power_ref_and_wait(card);
179	if (!err)
180		err = kctl->info(kctl, info);
181	snd_power_unref(card);
182	if (err >= 0) {
183		err = info->type;
184		*countp = info->count;
185	}
186	return err;
187}
188
189static int get_elem_size(snd_ctl_elem_type_t type, int count)
190{
191	switch (type) {
192	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
193		return sizeof(s64) * count;
194	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
195		return sizeof(int) * count;
196	case SNDRV_CTL_ELEM_TYPE_BYTES:
197		return 512;
198	case SNDRV_CTL_ELEM_TYPE_IEC958:
199		return sizeof(struct snd_aes_iec958);
200	default:
201		return -1;
202	}
203}
204
205static int copy_ctl_value_from_user(struct snd_card *card,
206				    struct snd_ctl_elem_value *data,
207				    void __user *userdata,
208				    void __user *valuep,
209				    int *typep, int *countp)
210{
211	struct snd_ctl_elem_value32 __user *data32 = userdata;
212	int i, type, size;
213	int count;
214	unsigned int indirect;
215
216	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
217		return -EFAULT;
218	if (get_user(indirect, &data32->indirect))
219		return -EFAULT;
220	if (indirect)
221		return -EINVAL;
222	type = get_ctl_type(card, &data->id, &count);
223	if (type < 0)
224		return type;
225
226	if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
227	    type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
228		for (i = 0; i < count; i++) {
229			s32 __user *intp = valuep;
230			int val;
231			if (get_user(val, &intp[i]))
232				return -EFAULT;
233			data->value.integer.value[i] = val;
234		}
235	} else {
236		size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
237		if (size < 0) {
238			dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
239			return -EINVAL;
240		}
241		if (copy_from_user(data->value.bytes.data, valuep, size))
242			return -EFAULT;
243	}
244
245	*typep = type;
246	*countp = count;
247	return 0;
248}
249
250/* restore the value to 32bit */
251static int copy_ctl_value_to_user(void __user *userdata,
252				  void __user *valuep,
253				  struct snd_ctl_elem_value *data,
254				  int type, int count)
255{
256	struct snd_ctl_elem_value32 __user *data32 = userdata;
257	int i, size;
258
259	if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
260	    type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
261		for (i = 0; i < count; i++) {
262			s32 __user *intp = valuep;
263			int val;
264			val = data->value.integer.value[i];
265			if (put_user(val, &intp[i]))
266				return -EFAULT;
267		}
268	} else {
269		size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
270		if (copy_to_user(valuep, data->value.bytes.data, size))
271			return -EFAULT;
272	}
273	if (copy_to_user(&data32->id, &data->id, sizeof(data32->id)))
274		return -EFAULT;
275	return 0;
276}
277
278static int ctl_elem_read_user(struct snd_card *card,
279			      void __user *userdata, void __user *valuep)
280{
281	struct snd_ctl_elem_value *data __free(kfree) = NULL;
282	int err, type, count;
283
284	data = kzalloc(sizeof(*data), GFP_KERNEL);
285	if (data == NULL)
286		return -ENOMEM;
287
288	err = copy_ctl_value_from_user(card, data, userdata, valuep,
289				       &type, &count);
290	if (err < 0)
291		return err;
292
293	err = snd_ctl_elem_read(card, data);
294	if (err < 0)
295		return err;
296	return copy_ctl_value_to_user(userdata, valuep, data, type, count);
297}
298
299static int ctl_elem_write_user(struct snd_ctl_file *file,
300			       void __user *userdata, void __user *valuep)
301{
302	struct snd_ctl_elem_value *data __free(kfree) = NULL;
303	struct snd_card *card = file->card;
304	int err, type, count;
305
306	data = kzalloc(sizeof(*data), GFP_KERNEL);
307	if (data == NULL)
308		return -ENOMEM;
309
310	err = copy_ctl_value_from_user(card, data, userdata, valuep,
311				       &type, &count);
312	if (err < 0)
313		return err;
314
315	err = snd_ctl_elem_write(card, file, data);
316	if (err < 0)
317		return err;
318	return copy_ctl_value_to_user(userdata, valuep, data, type, count);
319}
320
321static int snd_ctl_elem_read_user_compat(struct snd_card *card,
322					 struct snd_ctl_elem_value32 __user *data32)
323{
324	return ctl_elem_read_user(card, data32, &data32->value);
325}
326
327static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
328					  struct snd_ctl_elem_value32 __user *data32)
329{
330	return ctl_elem_write_user(file, data32, &data32->value);
331}
332
333#ifdef CONFIG_X86_X32_ABI
334static int snd_ctl_elem_read_user_x32(struct snd_card *card,
335				      struct snd_ctl_elem_value_x32 __user *data32)
336{
337	return ctl_elem_read_user(card, data32, &data32->value);
338}
339
340static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
341				       struct snd_ctl_elem_value_x32 __user *data32)
342{
343	return ctl_elem_write_user(file, data32, &data32->value);
344}
345#endif /* CONFIG_X86_X32_ABI */
346
347/* add or replace a user control */
348static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
349				   struct snd_ctl_elem_info32 __user *data32,
350				   int replace)
351{
352	struct snd_ctl_elem_info *data __free(kfree) = NULL;
353
354	data = kzalloc(sizeof(*data), GFP_KERNEL);
355	if (! data)
356		return -ENOMEM;
357
358	/* id, type, access, count */ \
359	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
360	    copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
361		return -EFAULT;
362	if (get_user(data->owner, &data32->owner))
363		return -EFAULT;
364	switch (data->type) {
365	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
366	case SNDRV_CTL_ELEM_TYPE_INTEGER:
367		if (get_user(data->value.integer.min, &data32->value.integer.min) ||
368		    get_user(data->value.integer.max, &data32->value.integer.max) ||
369		    get_user(data->value.integer.step, &data32->value.integer.step))
370			return -EFAULT;
371		break;
372	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
373		if (copy_from_user(&data->value.integer64,
374				   &data32->value.integer64,
375				   sizeof(data->value.integer64)))
376			return -EFAULT;
377		break;
378	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
379		if (copy_from_user(&data->value.enumerated,
380				   &data32->value.enumerated,
381				   sizeof(data->value.enumerated)))
382			return -EFAULT;
383		data->value.enumerated.names_ptr =
384			(uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
385		break;
386	default:
387		break;
388	}
389	return snd_ctl_elem_add(file, data, replace);
390}
391
392enum {
393	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
394	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
395	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
396	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
397	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
398	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
399#ifdef CONFIG_X86_X32_ABI
400	SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
401	SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
402#endif /* CONFIG_X86_X32_ABI */
403};
404
405static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
406{
407	struct snd_ctl_file *ctl;
408	struct snd_kctl_ioctl *p;
409	void __user *argp = compat_ptr(arg);
410	int err;
411
412	ctl = file->private_data;
413	if (snd_BUG_ON(!ctl || !ctl->card))
414		return -ENXIO;
415
416	switch (cmd) {
417	case SNDRV_CTL_IOCTL_PVERSION:
418	case SNDRV_CTL_IOCTL_CARD_INFO:
419	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
420	case SNDRV_CTL_IOCTL_POWER:
421	case SNDRV_CTL_IOCTL_POWER_STATE:
422	case SNDRV_CTL_IOCTL_ELEM_LOCK:
423	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
424	case SNDRV_CTL_IOCTL_ELEM_REMOVE:
425	case SNDRV_CTL_IOCTL_TLV_READ:
426	case SNDRV_CTL_IOCTL_TLV_WRITE:
427	case SNDRV_CTL_IOCTL_TLV_COMMAND:
428		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
429	case SNDRV_CTL_IOCTL_ELEM_LIST32:
430		return snd_ctl_elem_list_compat(ctl->card, argp);
431	case SNDRV_CTL_IOCTL_ELEM_INFO32:
432		return snd_ctl_elem_info_compat(ctl, argp);
433	case SNDRV_CTL_IOCTL_ELEM_READ32:
434		return snd_ctl_elem_read_user_compat(ctl->card, argp);
435	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
436		return snd_ctl_elem_write_user_compat(ctl, argp);
437	case SNDRV_CTL_IOCTL_ELEM_ADD32:
438		return snd_ctl_elem_add_compat(ctl, argp, 0);
439	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
440		return snd_ctl_elem_add_compat(ctl, argp, 1);
441#ifdef CONFIG_X86_X32_ABI
442	case SNDRV_CTL_IOCTL_ELEM_READ_X32:
443		return snd_ctl_elem_read_user_x32(ctl->card, argp);
444	case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
445		return snd_ctl_elem_write_user_x32(ctl, argp);
446#endif /* CONFIG_X86_X32_ABI */
447	}
448
449	guard(rwsem_read)(&snd_ioctl_rwsem);
450	list_for_each_entry(p, &snd_control_compat_ioctls, list) {
451		if (p->fioctl) {
452			err = p->fioctl(ctl->card, ctl, cmd, arg);
453			if (err != -ENOIOCTLCMD)
454				return err;
455		}
456	}
457	return -ENOIOCTLCMD;
458}
459