sound/core/control_compat.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * compat ioctls for control API
  *
  *   Copyright (c) by Takashi Iwai <tiwai@suse.de>
  */

 /* this file included from control.c */

 #include <linux/compat.h>
 #include <linux/slab.h>

 struct snd_ctl_elem_list32 {
 	u32 offset;
 	u32 space;
 	u32 used;
 	u32 count;
 	u32 pids;
 	unsigned char reserved[50];
 } /* don't set packed attribute here */;

 static int snd_ctl_elem_list_compat(struct snd_card *card,
 				    struct snd_ctl_elem_list32 __user *data32)
 {
 	struct snd_ctl_elem_list data = {};
 	compat_caddr_t ptr;
 	int err;

 	/* offset, space, used, count */
 	if (copy_from_user(&data, data32, 4 * sizeof(u32)))
 		return -EFAULT;
 	/* pids */
 	if (get_user(ptr, &data32->pids))
 		return -EFAULT;
 	data.pids = compat_ptr(ptr);
 	err = snd_ctl_elem_list(card, &data);
 	if (err < 0)
 		return err;
 	/* copy the result */
 	if (copy_to_user(data32, &data, 4 * sizeof(u32)))
 		return -EFAULT;
 	return 0;
 }

 /*
  * control element info
  * it uses union, so the things are not easy..
  */

 struct snd_ctl_elem_info32 {
 	struct snd_ctl_elem_id id; // the size of struct is same
 	s32 type;
 	u32 access;
 	u32 count;
 	s32 owner;
 	union {
 		struct {
 			s32 min;
 			s32 max;
 			s32 step;
 		} integer;
 		struct {
 			u64 min;
 			u64 max;
 			u64 step;
 		} integer64;
 		struct {
 			u32 items;
 			u32 item;
 			char name[64];
 			u64 names_ptr;
 			u32 names_length;
 		} enumerated;
 		unsigned char reserved[128];
 	} value;
 	unsigned char reserved[64];
 } __attribute__((packed));

 static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
 				    struct snd_ctl_elem_info32 __user *data32)
 {
 	struct snd_ctl_elem_info *data;
 	int err;

 	data = kzalloc(sizeof(*data), GFP_KERNEL);
 	if (! data)
 		return -ENOMEM;

 	err = -EFAULT;
 	/* copy id */
 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
 		goto error;
 	/* we need to copy the item index.
 	 * hope this doesn't break anything..
 	 */
 	if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
 		goto error;

 	err = snd_ctl_elem_info(ctl, data);
 	if (err < 0)
 		goto error;
 	/* restore info to 32bit */
 	err = -EFAULT;
 	/* id, type, access, count */
 	if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
 	    copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
 		goto error;
 	if (put_user(data->owner, &data32->owner))
 		goto error;
 	switch (data->type) {
 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
 		if (put_user(data->value.integer.min, &data32->value.integer.min) ||
 		    put_user(data->value.integer.max, &data32->value.integer.max) ||
 		    put_user(data->value.integer.step, &data32->value.integer.step))
 			goto error;
 		break;
 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 		if (copy_to_user(&data32->value.integer64,
 				 &data->value.integer64,
 				 sizeof(data->value.integer64)))
 			goto error;
 		break;
 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 		if (copy_to_user(&data32->value.enumerated,
 				 &data->value.enumerated,
 				 sizeof(data->value.enumerated)))
 			goto error;
 		break;
 	default:
 		break;
 	}
 	err = 0;
  error:
 	kfree(data);
 	return err;
 }

 /* read / write */
 struct snd_ctl_elem_value32 {
 	struct snd_ctl_elem_id id;
 	unsigned int indirect;	/* bit-field causes misalignment */
         union {
 		s32 integer[128];
 		unsigned char data[512];
 #ifndef CONFIG_X86_64
 		s64 integer64[64];
 #endif
         } value;
         unsigned char reserved[128];
 };

 #ifdef CONFIG_X86_X32_ABI
 /* x32 has a different alignment for 64bit values from ia32 */
 struct snd_ctl_elem_value_x32 {
 	struct snd_ctl_elem_id id;
 	unsigned int indirect;	/* bit-field causes misalignment */
 	union {
 		s32 integer[128];
 		unsigned char data[512];
 		s64 integer64[64];
 	} value;
 	unsigned char reserved[128];
 };
 #endif /* CONFIG_X86_X32_ABI */

 /* get the value type and count of the control */
 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
 			int *countp)
 {
 	struct snd_kcontrol *kctl;
 	struct snd_ctl_elem_info *info;
 	int err;

 	down_read(&card->controls_rwsem);
 	kctl = snd_ctl_find_id(card, id);
 	if (! kctl) {
 		up_read(&card->controls_rwsem);
 		return -ENOENT;
 	}
 	info = kzalloc(sizeof(*info), GFP_KERNEL);
 	if (info == NULL) {
 		up_read(&card->controls_rwsem);
 		return -ENOMEM;
 	}
 	info->id = *id;
 	err = snd_power_ref_and_wait(card);
 	if (!err)
 		err = kctl->info(kctl, info);
 	snd_power_unref(card);
 	up_read(&card->controls_rwsem);
 	if (err >= 0) {
 		err = info->type;
 		*countp = info->count;
 	}
 	kfree(info);
 	return err;
 }

 static int get_elem_size(snd_ctl_elem_type_t type, int count)
 {
 	switch (type) {
 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 		return sizeof(s64) * count;
 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 		return sizeof(int) * count;
 	case SNDRV_CTL_ELEM_TYPE_BYTES:
 		return 512;
 	case SNDRV_CTL_ELEM_TYPE_IEC958:
 		return sizeof(struct snd_aes_iec958);
 	default:
 		return -1;
 	}
 }

 static int copy_ctl_value_from_user(struct snd_card *card,
 				    struct snd_ctl_elem_value *data,
 				    void __user *userdata,
 				    void __user *valuep,
 				    int *typep, int *countp)
 {
 	struct snd_ctl_elem_value32 __user *data32 = userdata;
 	int i, type, size;
 	int count;
 	unsigned int indirect;

 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
 		return -EFAULT;
 	if (get_user(indirect, &data32->indirect))
 		return -EFAULT;
 	if (indirect)
 		return -EINVAL;
 	type = get_ctl_type(card, &data->id, &count);
 	if (type < 0)
 		return type;

 	if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 	    type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
 		for (i = 0; i < count; i++) {
 			s32 __user *intp = valuep;
 			int val;
 			if (get_user(val, &intp[i]))
 				return -EFAULT;
 			data->value.integer.value[i] = val;
 		}
 	} else {
 		size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
 		if (size < 0) {
 			dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
 			return -EINVAL;
 		}
 		if (copy_from_user(data->value.bytes.data, valuep, size))
 			return -EFAULT;
 	}

 	*typep = type;
 	*countp = count;
 	return 0;
 }

 /* restore the value to 32bit */
 static int copy_ctl_value_to_user(void __user *userdata,
 				  void __user *valuep,
 				  struct snd_ctl_elem_value *data,
 				  int type, int count)
 {
 	struct snd_ctl_elem_value32 __user *data32 = userdata;
 	int i, size;

 	if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 	    type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
 		for (i = 0; i < count; i++) {
 			s32 __user *intp = valuep;
 			int val;
 			val = data->value.integer.value[i];
 			if (put_user(val, &intp[i]))
 				return -EFAULT;
 		}
 	} else {
 		size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
 		if (copy_to_user(valuep, data->value.bytes.data, size))
 			return -EFAULT;
 	}
 	if (copy_to_user(&data32->id, &data->id, sizeof(data32->id)))
 		return -EFAULT;
 	return 0;
 }

 static int ctl_elem_read_user(struct snd_card *card,
 			      void __user *userdata, void __user *valuep)
 {
 	struct snd_ctl_elem_value *data;
 	int err, type, count;

 	data = kzalloc(sizeof(*data), GFP_KERNEL);
 	if (data == NULL)
 		return -ENOMEM;

 	err = copy_ctl_value_from_user(card, data, userdata, valuep,
 				       &type, &count);
 	if (err < 0)
 		goto error;

 	err = snd_ctl_elem_read(card, data);
 	if (err < 0)
 		goto error;
 	err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
  error:
 	kfree(data);
 	return err;
 }

 static int ctl_elem_write_user(struct snd_ctl_file *file,
 			       void __user *userdata, void __user *valuep)
 {
 	struct snd_ctl_elem_value *data;
 	struct snd_card *card = file->card;
 	int err, type, count;

 	data = kzalloc(sizeof(*data), GFP_KERNEL);
 	if (data == NULL)
 		return -ENOMEM;

 	err = copy_ctl_value_from_user(card, data, userdata, valuep,
 				       &type, &count);
 	if (err < 0)
 		goto error;

 	err = snd_ctl_elem_write(card, file, data);
 	if (err < 0)
 		goto error;
 	err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
  error:
 	kfree(data);
 	return err;
 }

 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 					 struct snd_ctl_elem_value32 __user *data32)
 {
 	return ctl_elem_read_user(card, data32, &data32->value);
 }

 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
 					  struct snd_ctl_elem_value32 __user *data32)
 {
 	return ctl_elem_write_user(file, data32, &data32->value);
 }

 #ifdef CONFIG_X86_X32_ABI
 static int snd_ctl_elem_read_user_x32(struct snd_card *card,
 				      struct snd_ctl_elem_value_x32 __user *data32)
 {
 	return ctl_elem_read_user(card, data32, &data32->value);
 }

 static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
 				       struct snd_ctl_elem_value_x32 __user *data32)
 {
 	return ctl_elem_write_user(file, data32, &data32->value);
 }
 #endif /* CONFIG_X86_X32_ABI */

 /* add or replace a user control */
 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
 				   struct snd_ctl_elem_info32 __user *data32,
 				   int replace)
 {
 	struct snd_ctl_elem_info *data;
 	int err;

 	data = kzalloc(sizeof(*data), GFP_KERNEL);
 	if (! data)
 		return -ENOMEM;

 	err = -EFAULT;
 	/* id, type, access, count */ \
 	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
 	    copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
 		goto error;
 	if (get_user(data->owner, &data32->owner))
 		goto error;
 	switch (data->type) {
 	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 	case SNDRV_CTL_ELEM_TYPE_INTEGER:
 		if (get_user(data->value.integer.min, &data32->value.integer.min) ||
 		    get_user(data->value.integer.max, &data32->value.integer.max) ||
 		    get_user(data->value.integer.step, &data32->value.integer.step))
 			goto error;
 		break;
 	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 		if (copy_from_user(&data->value.integer64,
 				   &data32->value.integer64,
 				   sizeof(data->value.integer64)))
 			goto error;
 		break;
 	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 		if (copy_from_user(&data->value.enumerated,
 				   &data32->value.enumerated,
 				   sizeof(data->value.enumerated)))
 			goto error;
 		data->value.enumerated.names_ptr =
 			(uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
 		break;
 	default:
 		break;
 	}
 	err = snd_ctl_elem_add(file, data, replace);
  error:
 	kfree(data);
 	return err;
 }

 enum {
 	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
 	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
 	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
 	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
 	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
 	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 #ifdef CONFIG_X86_X32_ABI
 	SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
 	SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
 #endif /* CONFIG_X86_X32_ABI */
 };

 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct snd_ctl_file *ctl;
 	struct snd_kctl_ioctl *p;
 	void __user *argp = compat_ptr(arg);
 	int err;

 	ctl = file->private_data;
 	if (snd_BUG_ON(!ctl || !ctl->card))
 		return -ENXIO;

 	switch (cmd) {
 	case SNDRV_CTL_IOCTL_PVERSION:
 	case SNDRV_CTL_IOCTL_CARD_INFO:
 	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
 	case SNDRV_CTL_IOCTL_POWER:
 	case SNDRV_CTL_IOCTL_POWER_STATE:
 	case SNDRV_CTL_IOCTL_ELEM_LOCK:
 	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
 	case SNDRV_CTL_IOCTL_ELEM_REMOVE:
 	case SNDRV_CTL_IOCTL_TLV_READ:
 	case SNDRV_CTL_IOCTL_TLV_WRITE:
 	case SNDRV_CTL_IOCTL_TLV_COMMAND:
 		return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
 	case SNDRV_CTL_IOCTL_ELEM_LIST32:
 		return snd_ctl_elem_list_compat(ctl->card, argp);
 	case SNDRV_CTL_IOCTL_ELEM_INFO32:
 		return snd_ctl_elem_info_compat(ctl, argp);
 	case SNDRV_CTL_IOCTL_ELEM_READ32:
 		return snd_ctl_elem_read_user_compat(ctl->card, argp);
 	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
 		return snd_ctl_elem_write_user_compat(ctl, argp);
 	case SNDRV_CTL_IOCTL_ELEM_ADD32:
 		return snd_ctl_elem_add_compat(ctl, argp, 0);
 	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
 		return snd_ctl_elem_add_compat(ctl, argp, 1);
 #ifdef CONFIG_X86_X32_ABI
 	case SNDRV_CTL_IOCTL_ELEM_READ_X32:
 		return snd_ctl_elem_read_user_x32(ctl->card, argp);
 	case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
 		return snd_ctl_elem_write_user_x32(ctl, argp);
 #endif /* CONFIG_X86_X32_ABI */
 	}

 	down_read(&snd_ioctl_rwsem);
 	list_for_each_entry(p, &snd_control_compat_ioctls, list) {
 		if (p->fioctl) {
 			err = p->fioctl(ctl->card, ctl, cmd, arg);
 			if (err != -ENOIOCTLCMD) {
 				up_read(&snd_ioctl_rwsem);
 				return err;
 			}
 		}
 	}
 	up_read(&snd_ioctl_rwsem);
 	return -ENOIOCTLCMD;
 }
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* compat ioctls for control API
	*
	* Copyright (c) by Takashi Iwai <tiwai@suse.de>
	*/

	/* this file included from control.c */

	#include <linux/compat.h>
	#include <linux/slab.h>

	struct snd_ctl_elem_list32 {
	u32 offset;
	u32 space;
	u32 used;
	u32 count;
	u32 pids;
	unsigned char reserved[50];
	} /* don't set packed attribute here */;

	static int snd_ctl_elem_list_compat(struct snd_card *card,
	struct snd_ctl_elem_list32 __user *data32)
	{
	struct snd_ctl_elem_list data = {};
	compat_caddr_t ptr;
	int err;

	/* offset, space, used, count */
	if (copy_from_user(&data, data32, 4 * sizeof(u32)))
	return -EFAULT;
	/* pids */
	if (get_user(ptr, &data32->pids))
	return -EFAULT;
	data.pids = compat_ptr(ptr);
	err = snd_ctl_elem_list(card, &data);
	if (err < 0)
	return err;
	/* copy the result */
	if (copy_to_user(data32, &data, 4 * sizeof(u32)))
	return -EFAULT;
	return 0;
	}

	/*
	* control element info
	* it uses union, so the things are not easy..
	*/

	struct snd_ctl_elem_info32 {
	struct snd_ctl_elem_id id; // the size of struct is same
	s32 type;
	u32 access;
	u32 count;
	s32 owner;
	union {
	struct {
	s32 min;
	s32 max;
	s32 step;
	} integer;
	struct {
	u64 min;
	u64 max;
	u64 step;
	} integer64;
	struct {
	u32 items;
	u32 item;
	char name[64];
	u64 names_ptr;
	u32 names_length;
	} enumerated;
	unsigned char reserved[128];
	} value;
	unsigned char reserved[64];
	} __attribute__((packed));

	static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
	struct snd_ctl_elem_info32 __user *data32)
	{
	struct snd_ctl_elem_info *data;
	int err;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (! data)
	return -ENOMEM;

	err = -EFAULT;
	/* copy id */
	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
	goto error;
	/* we need to copy the item index.
	* hope this doesn't break anything..
	*/
	if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
	goto error;

	err = snd_ctl_elem_info(ctl, data);
	if (err < 0)
	goto error;
	/* restore info to 32bit */
	err = -EFAULT;
	/* id, type, access, count */
	if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) \|\|
	copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
	goto error;
	if (put_user(data->owner, &data32->owner))
	goto error;
	switch (data->type) {
	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
	case SNDRV_CTL_ELEM_TYPE_INTEGER:
	if (put_user(data->value.integer.min, &data32->value.integer.min) \|\|
	put_user(data->value.integer.max, &data32->value.integer.max) \|\|
	put_user(data->value.integer.step, &data32->value.integer.step))
	goto error;
	break;
	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
	if (copy_to_user(&data32->value.integer64,
	&data->value.integer64,
	sizeof(data->value.integer64)))
	goto error;
	break;
	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
	if (copy_to_user(&data32->value.enumerated,
	&data->value.enumerated,
	sizeof(data->value.enumerated)))
	goto error;
	break;
	default:
	break;
	}
	err = 0;
	error:
	kfree(data);
	return err;
	}

	/* read / write */
	struct snd_ctl_elem_value32 {
	struct snd_ctl_elem_id id;
	unsigned int indirect; /* bit-field causes misalignment */
	union {
	s32 integer[128];
	unsigned char data[512];
	#ifndef CONFIG_X86_64
	s64 integer64[64];
	#endif
	} value;
	unsigned char reserved[128];
	};

	#ifdef CONFIG_X86_X32_ABI
	/* x32 has a different alignment for 64bit values from ia32 */
	struct snd_ctl_elem_value_x32 {
	struct snd_ctl_elem_id id;
	unsigned int indirect; /* bit-field causes misalignment */
	union {
	s32 integer[128];
	unsigned char data[512];
	s64 integer64[64];
	} value;
	unsigned char reserved[128];
	};
	#endif /* CONFIG_X86_X32_ABI */

	/* get the value type and count of the control */
	static int get_ctl_type(struct snd_card card, struct snd_ctl_elem_id id,
	int *countp)
	{
	struct snd_kcontrol *kctl;
	struct snd_ctl_elem_info *info;
	int err;

	down_read(&card->controls_rwsem);
	kctl = snd_ctl_find_id(card, id);
	if (! kctl) {
	up_read(&card->controls_rwsem);
	return -ENOENT;
	}
	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (info == NULL) {
	up_read(&card->controls_rwsem);
	return -ENOMEM;
	}
	info->id = *id;
	err = snd_power_ref_and_wait(card);
	if (!err)
	err = kctl->info(kctl, info);
	snd_power_unref(card);
	up_read(&card->controls_rwsem);
	if (err >= 0) {
	err = info->type;
	*countp = info->count;
	}
	kfree(info);
	return err;
	}

	static int get_elem_size(snd_ctl_elem_type_t type, int count)
	{
	switch (type) {
	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
	return sizeof(s64) * count;
	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
	return sizeof(int) * count;
	case SNDRV_CTL_ELEM_TYPE_BYTES:
	return 512;
	case SNDRV_CTL_ELEM_TYPE_IEC958:
	return sizeof(struct snd_aes_iec958);
	default:
	return -1;
	}
	}

	static int copy_ctl_value_from_user(struct snd_card *card,
	struct snd_ctl_elem_value *data,
	void __user *userdata,
	void __user *valuep,
	int typep, int countp)
	{
	struct snd_ctl_elem_value32 __user *data32 = userdata;
	int i, type, size;
	int count;
	unsigned int indirect;

	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
	return -EFAULT;
	if (get_user(indirect, &data32->indirect))
	return -EFAULT;
	if (indirect)
	return -EINVAL;
	type = get_ctl_type(card, &data->id, &count);
	if (type < 0)
	return type;

	if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN \|\|
	type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
	for (i = 0; i < count; i++) {
	s32 __user *intp = valuep;
	int val;
	if (get_user(val, &intp[i]))
	return -EFAULT;
	data->value.integer.value[i] = val;
	}
	} else {
	size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
	if (size < 0) {
	dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
	return -EINVAL;
	}
	if (copy_from_user(data->value.bytes.data, valuep, size))
	return -EFAULT;
	}

	*typep = type;
	*countp = count;
	return 0;
	}

	/* restore the value to 32bit */
	static int copy_ctl_value_to_user(void __user *userdata,
	void __user *valuep,
	struct snd_ctl_elem_value *data,
	int type, int count)
	{
	struct snd_ctl_elem_value32 __user *data32 = userdata;
	int i, size;

	if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN \|\|
	type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
	for (i = 0; i < count; i++) {
	s32 __user *intp = valuep;
	int val;
	val = data->value.integer.value[i];
	if (put_user(val, &intp[i]))
	return -EFAULT;
	}
	} else {
	size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
	if (copy_to_user(valuep, data->value.bytes.data, size))
	return -EFAULT;
	}
	if (copy_to_user(&data32->id, &data->id, sizeof(data32->id)))
	return -EFAULT;
	return 0;
	}

	static int ctl_elem_read_user(struct snd_card *card,
	void __user userdata, void __user valuep)
	{
	struct snd_ctl_elem_value *data;
	int err, type, count;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (data == NULL)
	return -ENOMEM;

	err = copy_ctl_value_from_user(card, data, userdata, valuep,
	&type, &count);
	if (err < 0)
	goto error;

	err = snd_ctl_elem_read(card, data);
	if (err < 0)
	goto error;
	err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
	error:
	kfree(data);
	return err;
	}

	static int ctl_elem_write_user(struct snd_ctl_file *file,
	void __user userdata, void __user valuep)
	{
	struct snd_ctl_elem_value *data;
	struct snd_card *card = file->card;
	int err, type, count;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (data == NULL)
	return -ENOMEM;

	err = copy_ctl_value_from_user(card, data, userdata, valuep,
	&type, &count);
	if (err < 0)
	goto error;

	err = snd_ctl_elem_write(card, file, data);
	if (err < 0)
	goto error;
	err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
	error:
	kfree(data);
	return err;
	}

	static int snd_ctl_elem_read_user_compat(struct snd_card *card,
	struct snd_ctl_elem_value32 __user *data32)
	{
	return ctl_elem_read_user(card, data32, &data32->value);
	}

	static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
	struct snd_ctl_elem_value32 __user *data32)
	{
	return ctl_elem_write_user(file, data32, &data32->value);
	}

	#ifdef CONFIG_X86_X32_ABI
	static int snd_ctl_elem_read_user_x32(struct snd_card *card,
	struct snd_ctl_elem_value_x32 __user *data32)
	{
	return ctl_elem_read_user(card, data32, &data32->value);
	}

	static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
	struct snd_ctl_elem_value_x32 __user *data32)
	{
	return ctl_elem_write_user(file, data32, &data32->value);
	}
	#endif /* CONFIG_X86_X32_ABI */

	/* add or replace a user control */
	static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
	struct snd_ctl_elem_info32 __user *data32,
	int replace)
	{
	struct snd_ctl_elem_info *data;
	int err;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (! data)
	return -ENOMEM;

	err = -EFAULT;
	/* id, type, access, count */ \
	if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) \|\|
	copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
	goto error;
	if (get_user(data->owner, &data32->owner))
	goto error;
	switch (data->type) {
	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
	case SNDRV_CTL_ELEM_TYPE_INTEGER:
	if (get_user(data->value.integer.min, &data32->value.integer.min) \|\|
	get_user(data->value.integer.max, &data32->value.integer.max) \|\|
	get_user(data->value.integer.step, &data32->value.integer.step))
	goto error;
	break;
	case SNDRV_CTL_ELEM_TYPE_INTEGER64:
	if (copy_from_user(&data->value.integer64,
	&data32->value.integer64,
	sizeof(data->value.integer64)))
	goto error;
	break;
	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
	if (copy_from_user(&data->value.enumerated,
	&data32->value.enumerated,
	sizeof(data->value.enumerated)))
	goto error;
	data->value.enumerated.names_ptr =
	(uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
	break;
	default:
	break;
	}
	err = snd_ctl_elem_add(file, data, replace);
	error:
	kfree(data);
	return err;
	}

	enum {
	SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
	SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
	SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
	SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
	SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
	SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
	#ifdef CONFIG_X86_X32_ABI
	SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
	SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
	#endif /* CONFIG_X86_X32_ABI */
	};

	static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
	{
	struct snd_ctl_file *ctl;
	struct snd_kctl_ioctl *p;
	void __user *argp = compat_ptr(arg);
	int err;

	ctl = file->private_data;
	if (snd_BUG_ON(!ctl \|\| !ctl->card))
	return -ENXIO;

	switch (cmd) {
	case SNDRV_CTL_IOCTL_PVERSION:
	case SNDRV_CTL_IOCTL_CARD_INFO:
	case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
	case SNDRV_CTL_IOCTL_POWER:
	case SNDRV_CTL_IOCTL_POWER_STATE:
	case SNDRV_CTL_IOCTL_ELEM_LOCK:
	case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
	case SNDRV_CTL_IOCTL_ELEM_REMOVE:
	case SNDRV_CTL_IOCTL_TLV_READ:
	case SNDRV_CTL_IOCTL_TLV_WRITE:
	case SNDRV_CTL_IOCTL_TLV_COMMAND:
	return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
	case SNDRV_CTL_IOCTL_ELEM_LIST32:
	return snd_ctl_elem_list_compat(ctl->card, argp);
	case SNDRV_CTL_IOCTL_ELEM_INFO32:
	return snd_ctl_elem_info_compat(ctl, argp);
	case SNDRV_CTL_IOCTL_ELEM_READ32:
	return snd_ctl_elem_read_user_compat(ctl->card, argp);
	case SNDRV_CTL_IOCTL_ELEM_WRITE32:
	return snd_ctl_elem_write_user_compat(ctl, argp);
	case SNDRV_CTL_IOCTL_ELEM_ADD32:
	return snd_ctl_elem_add_compat(ctl, argp, 0);
	case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
	return snd_ctl_elem_add_compat(ctl, argp, 1);
	#ifdef CONFIG_X86_X32_ABI
	case SNDRV_CTL_IOCTL_ELEM_READ_X32:
	return snd_ctl_elem_read_user_x32(ctl->card, argp);
	case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
	return snd_ctl_elem_write_user_x32(ctl, argp);
	#endif /* CONFIG_X86_X32_ABI */
	}

	down_read(&snd_ioctl_rwsem);
	list_for_each_entry(p, &snd_control_compat_ioctls, list) {
	if (p->fioctl) {
	err = p->fioctl(ctl->card, ctl, cmd, arg);
	if (err != -ENOIOCTLCMD) {
	up_read(&snd_ioctl_rwsem);
	return err;
	}
	}
	}
	up_read(&snd_ioctl_rwsem);
	return -ENOIOCTLCMD;
	}