// 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];
} __packed;

static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
                                    struct snd_ctl_elem_info32 __user *data32)
{
        struct snd_card *card = ctl->card;
        int err;
        struct snd_ctl_elem_info *data __free(kfree) =
                kzalloc_obj(*data);

        if (! data)
                return -ENOMEM;

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

        err = snd_power_ref_and_wait(card);
        if (err < 0)
                return err;
        err = snd_ctl_elem_info(ctl, data);
        snd_power_unref(card);
        if (err < 0)
                return err;
        /* restore info to 32bit */
        /* 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)))
                return -EFAULT;
        if (put_user(data->owner, &data32->owner))
                return -EFAULT;
        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))
                        return -EFAULT;
                break;
        case SNDRV_CTL_ELEM_TYPE_INTEGER64:
                if (copy_to_user(&data32->value.integer64,
                                 &data->value.integer64,
                                 sizeof(data->value.integer64)))
                        return -EFAULT;
                break;
        case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
                if (copy_to_user(&data32->value.enumerated,
                                 &data->value.enumerated,
                                 sizeof(data->value.enumerated)))
                        return -EFAULT;
                break;
        default:
                break;
        }
        return 0;
}

/* 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;
        int err;

        guard(rwsem_read)(&card->controls_rwsem);
        kctl = snd_ctl_find_id(card, id);
        if (!kctl)
                return -ENOENT;

        struct snd_ctl_elem_info *info __free(kfree) =
                kzalloc_obj(*info);
        if (info == NULL)
                return -ENOMEM;
        info->id = *id;
        err = kctl->info(kctl, info);
        if (err >= 0) {
                err = info->type;
                *countp = info->count;
        }
        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)
{
        int err, type, count;
        struct snd_ctl_elem_value *data __free(kfree) =
                kzalloc_obj(*data);

        if (data == NULL)
                return -ENOMEM;

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

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

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

        err = snd_power_ref_and_wait(card);
        if (err < 0)
                return err;
        err = __ctl_elem_read_user(card, userdata, valuep);
        snd_power_unref(card);
        return err;
}

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

        if (data == NULL)
                return -ENOMEM;

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

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

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

        err = snd_power_ref_and_wait(card);
        if (err < 0)
                return err;
        err = __ctl_elem_write_user(file, userdata, valuep);
        snd_power_unref(card);
        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 __free(kfree) =
                kzalloc_obj(*data);

        if (! data)
                return -ENOMEM;

        /* 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)))
                return -EFAULT;
        if (get_user(data->owner, &data32->owner))
                return -EFAULT;
        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))
                        return -EFAULT;
                break;
        case SNDRV_CTL_ELEM_TYPE_INTEGER64:
                if (copy_from_user(&data->value.integer64,
                                   &data32->value.integer64,
                                   sizeof(data->value.integer64)))
                        return -EFAULT;
                break;
        case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
                if (copy_from_user(&data->value.enumerated,
                                   &data32->value.enumerated,
                                   sizeof(data->value.enumerated)))
                        return -EFAULT;
                data->value.enumerated.names_ptr =
                        (uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
                break;
        default:
                break;
        }
        return snd_ctl_elem_add(file, data, replace);
}  

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 */
        }

        guard(rwsem_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)
                                return err;
                }
        }
        return -ENOIOCTLCMD;
}