LXR linux/sound/core/control

   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} __attribute__((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;
  83        int err;
  84
  85        data = kzalloc(sizeof(*data), GFP_KERNEL);
  86        if (! data)
  87                return -ENOMEM;
  88
  89        err = -EFAULT;
  90        /* copy id */
  91        if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
  92                goto error;
  93        /* we need to copy the item index.
  94         * hope this doesn't break anything..
  95         */
  96        if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
  97                goto error;
  98
  99        err = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
 100        if (err < 0)
 101                goto error;
 102        err = snd_ctl_elem_info(ctl, data);
 103        if (err < 0)
 104                goto error;
 105        /* restore info to 32bit */
 106        err = -EFAULT;
 107        /* id, type, access, count */
 108        if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
 109            copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
 110                goto error;
 111        if (put_user(data->owner, &data32->owner))
 112                goto error;
 113        switch (data->type) {
 114        case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 115        case SNDRV_CTL_ELEM_TYPE_INTEGER:
 116                if (put_user(data->value.integer.min, &data32->value.integer.min) ||
 117                    put_user(data->value.integer.max, &data32->value.integer.max) ||
 118                    put_user(data->value.integer.step, &data32->value.integer.step))
 119                        goto error;
 120                break;
 121        case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 122                if (copy_to_user(&data32->value.integer64,
 123                                 &data->value.integer64,
 124                                 sizeof(data->value.integer64)))
 125                        goto error;
 126                break;
 127        case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 128                if (copy_to_user(&data32->value.enumerated,
 129                                 &data->value.enumerated,
 130                                 sizeof(data->value.enumerated)))
 131                        goto error;
 132                break;
 133        default:
 134                break;
 135        }
 136        err = 0;
 137 error:
 138        kfree(data);
 139        return err;
 140}
 141
 142/* read / write */
 143struct snd_ctl_elem_value32 {
 144        struct snd_ctl_elem_id id;
 145        unsigned int indirect;  /* bit-field causes misalignment */
 146        union {
 147                s32 integer[128];
 148                unsigned char data[512];
 149#ifndef CONFIG_X86_64
 150                s64 integer64[64];
 151#endif
 152        } value;
 153        unsigned char reserved[128];
 154};
 155
 156#ifdef CONFIG_X86_X32
 157/* x32 has a different alignment for 64bit values from ia32 */
 158struct snd_ctl_elem_value_x32 {
 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                s64 integer64[64];
 165        } value;
 166        unsigned char reserved[128];
 167};
 168#endif /* CONFIG_X86_X32 */
 169
 170/* get the value type and count of the control */
 171static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
 172                        int *countp)
 173{
 174        struct snd_kcontrol *kctl;
 175        struct snd_ctl_elem_info *info;
 176        int err;
 177
 178        down_read(&card->controls_rwsem);
 179        kctl = snd_ctl_find_id(card, id);
 180        if (! kctl) {
 181                up_read(&card->controls_rwsem);
 182                return -ENOENT;
 183        }
 184        info = kzalloc(sizeof(*info), GFP_KERNEL);
 185        if (info == NULL) {
 186                up_read(&card->controls_rwsem);
 187                return -ENOMEM;
 188        }
 189        info->id = *id;
 190        err = kctl->info(kctl, info);
 191        up_read(&card->controls_rwsem);
 192        if (err >= 0) {
 193                err = info->type;
 194                *countp = info->count;
 195        }
 196        kfree(info);
 197        return err;
 198}
 199
 200static int get_elem_size(int type, int count)
 201{
 202        switch (type) {
 203        case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 204                return sizeof(s64) * count;
 205        case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 206                return sizeof(int) * count;
 207        case SNDRV_CTL_ELEM_TYPE_BYTES:
 208                return 512;
 209        case SNDRV_CTL_ELEM_TYPE_IEC958:
 210                return sizeof(struct snd_aes_iec958);
 211        default:
 212                return -1;
 213        }
 214}
 215
 216static int copy_ctl_value_from_user(struct snd_card *card,
 217                                    struct snd_ctl_elem_value *data,
 218                                    void __user *userdata,
 219                                    void __user *valuep,
 220                                    int *typep, int *countp)
 221{
 222        struct snd_ctl_elem_value32 __user *data32 = userdata;
 223        int i, type, size;
 224        int 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                        s32 __user *intp = valuep;
 241                        int val;
 242                        if (get_user(val, &intp[i]))
 243                                return -EFAULT;
 244                        data->value.integer.value[i] = val;
 245                }
 246        } else {
 247                size = get_elem_size(type, count);
 248                if (size < 0) {
 249                        dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
 250                        return -EINVAL;
 251                }
 252                if (copy_from_user(data->value.bytes.data, valuep, size))
 253                        return -EFAULT;
 254        }
 255
 256        *typep = type;
 257        *countp = count;
 258        return 0;
 259}
 260
 261/* restore the value to 32bit */
 262static int copy_ctl_value_to_user(void __user *userdata,
 263                                  void __user *valuep,
 264                                  struct snd_ctl_elem_value *data,
 265                                  int type, int count)
 266{
 267        int i, size;
 268
 269        if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 270            type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
 271                for (i = 0; i < count; i++) {
 272                        s32 __user *intp = valuep;
 273                        int val;
 274                        val = data->value.integer.value[i];
 275                        if (put_user(val, &intp[i]))
 276                                return -EFAULT;
 277                }
 278        } else {
 279                size = get_elem_size(type, count);
 280                if (copy_to_user(valuep, data->value.bytes.data, size))
 281                        return -EFAULT;
 282        }
 283        return 0;
 284}
 285
 286static int ctl_elem_read_user(struct snd_card *card,
 287                              void __user *userdata, void __user *valuep)
 288{
 289        struct snd_ctl_elem_value *data;
 290        int err, type, count;
 291
 292        data = kzalloc(sizeof(*data), GFP_KERNEL);
 293        if (data == NULL)
 294                return -ENOMEM;
 295
 296        err = copy_ctl_value_from_user(card, data, userdata, valuep,
 297                                       &type, &count);
 298        if (err < 0)
 299                goto error;
 300
 301        err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
 302        if (err < 0)
 303                goto error;
 304        err = snd_ctl_elem_read(card, data);
 305        if (err < 0)
 306                goto error;
 307        err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
 308 error:
 309        kfree(data);
 310        return err;
 311}
 312
 313static int ctl_elem_write_user(struct snd_ctl_file *file,
 314                               void __user *userdata, void __user *valuep)
 315{
 316        struct snd_ctl_elem_value *data;
 317        struct snd_card *card = file->card;
 318        int err, type, count;
 319
 320        data = kzalloc(sizeof(*data), GFP_KERNEL);
 321        if (data == NULL)
 322                return -ENOMEM;
 323
 324        err = copy_ctl_value_from_user(card, data, userdata, valuep,
 325                                       &type, &count);
 326        if (err < 0)
 327                goto error;
 328
 329        err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
 330        if (err < 0)
 331                goto error;
 332        err = snd_ctl_elem_write(card, file, data);
 333        if (err < 0)
 334                goto error;
 335        err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
 336 error:
 337        kfree(data);
 338        return err;
 339}
 340
 341static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 342                                         struct snd_ctl_elem_value32 __user *data32)
 343{
 344        return ctl_elem_read_user(card, data32, &data32->value);
 345}
 346
 347static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
 348                                          struct snd_ctl_elem_value32 __user *data32)
 349{
 350        return ctl_elem_write_user(file, data32, &data32->value);
 351}
 352
 353#ifdef CONFIG_X86_X32
 354static int snd_ctl_elem_read_user_x32(struct snd_card *card,
 355                                      struct snd_ctl_elem_value_x32 __user *data32)
 356{
 357        return ctl_elem_read_user(card, data32, &data32->value);
 358}
 359
 360static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
 361                                       struct snd_ctl_elem_value_x32 __user *data32)
 362{
 363        return ctl_elem_write_user(file, data32, &data32->value);
 364}
 365#endif /* CONFIG_X86_X32 */
 366
 367/* add or replace a user control */
 368static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
 369                                   struct snd_ctl_elem_info32 __user *data32,
 370                                   int replace)
 371{
 372        struct snd_ctl_elem_info *data;
 373        int err;
 374
 375        data = kzalloc(sizeof(*data), GFP_KERNEL);
 376        if (! data)
 377                return -ENOMEM;
 378
 379        err = -EFAULT;
 380        /* id, type, access, count */ \
 381        if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
 382            copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
 383                goto error;
 384        if (get_user(data->owner, &data32->owner))
 385                goto error;
 386        switch (data->type) {
 387        case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 388        case SNDRV_CTL_ELEM_TYPE_INTEGER:
 389                if (get_user(data->value.integer.min, &data32->value.integer.min) ||
 390                    get_user(data->value.integer.max, &data32->value.integer.max) ||
 391                    get_user(data->value.integer.step, &data32->value.integer.step))
 392                        goto error;
 393                break;
 394        case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 395                if (copy_from_user(&data->value.integer64,
 396                                   &data32->value.integer64,
 397                                   sizeof(data->value.integer64)))
 398                        goto error;
 399                break;
 400        case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 401                if (copy_from_user(&data->value.enumerated,
 402                                   &data32->value.enumerated,
 403                                   sizeof(data->value.enumerated)))
 404                        goto error;
 405                data->value.enumerated.names_ptr =
 406                        (uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
 407                break;
 408        default:
 409                break;
 410        }
 411        err = snd_ctl_elem_add(file, data, replace);
 412 error:
 413        kfree(data);
 414        return err;
 415}  
 416
 417enum {
 418        SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
 419        SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
 420        SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
 421        SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
 422        SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
 423        SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 424#ifdef CONFIG_X86_X32
 425        SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
 426        SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
 427#endif /* CONFIG_X86_X32 */
 428};
 429
 430static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 431{
 432        struct snd_ctl_file *ctl;
 433        struct snd_kctl_ioctl *p;
 434        void __user *argp = compat_ptr(arg);
 435        int err;
 436
 437        ctl = file->private_data;
 438        if (snd_BUG_ON(!ctl || !ctl->card))
 439                return -ENXIO;
 440
 441        switch (cmd) {
 442        case SNDRV_CTL_IOCTL_PVERSION:
 443        case SNDRV_CTL_IOCTL_CARD_INFO:
 444        case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
 445        case SNDRV_CTL_IOCTL_POWER:
 446        case SNDRV_CTL_IOCTL_POWER_STATE:
 447        case SNDRV_CTL_IOCTL_ELEM_LOCK:
 448        case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
 449        case SNDRV_CTL_IOCTL_ELEM_REMOVE:
 450        case SNDRV_CTL_IOCTL_TLV_READ:
 451        case SNDRV_CTL_IOCTL_TLV_WRITE:
 452        case SNDRV_CTL_IOCTL_TLV_COMMAND:
 453                return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
 454        case SNDRV_CTL_IOCTL_ELEM_LIST32:
 455                return snd_ctl_elem_list_compat(ctl->card, argp);
 456        case SNDRV_CTL_IOCTL_ELEM_INFO32:
 457                return snd_ctl_elem_info_compat(ctl, argp);
 458        case SNDRV_CTL_IOCTL_ELEM_READ32:
 459                return snd_ctl_elem_read_user_compat(ctl->card, argp);
 460        case SNDRV_CTL_IOCTL_ELEM_WRITE32:
 461                return snd_ctl_elem_write_user_compat(ctl, argp);
 462        case SNDRV_CTL_IOCTL_ELEM_ADD32:
 463                return snd_ctl_elem_add_compat(ctl, argp, 0);
 464        case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
 465                return snd_ctl_elem_add_compat(ctl, argp, 1);
 466#ifdef CONFIG_X86_X32
 467        case SNDRV_CTL_IOCTL_ELEM_READ_X32:
 468                return snd_ctl_elem_read_user_x32(ctl->card, argp);
 469        case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
 470                return snd_ctl_elem_write_user_x32(ctl, argp);
 471#endif /* CONFIG_X86_X32 */
 472        }
 473
 474        down_read(&snd_ioctl_rwsem);
 475        list_for_each_entry(p, &snd_control_compat_ioctls, list) {
 476                if (p->fioctl) {
 477                        err = p->fioctl(ctl->card, ctl, cmd, arg);
 478                        if (err != -ENOIOCTLCMD) {
 479                                up_read(&snd_ioctl_rwsem);
 480                                return err;
 481                        }
 482                }
 483        }
 484        up_read(&snd_ioctl_rwsem);
 485        return -ENOIOCTLCMD;
 486}
 487