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 __user *data;
  26        compat_caddr_t ptr;
  27        int err;
  28
  29        data = compat_alloc_user_space(sizeof(*data));
  30
  31        /* offset, space, used, count */
  32        if (copy_in_user(data, data32, 4 * sizeof(u32)))
  33                return -EFAULT;
  34        /* pids */
  35        if (get_user(ptr, &data32->pids) ||
  36            put_user(compat_ptr(ptr), &data->pids))
  37                return -EFAULT;
  38        err = snd_ctl_elem_list(card, data);
  39        if (err < 0)
  40                return err;
  41        /* copy the result */
  42        if (copy_in_user(data32, data, 4 * sizeof(u32)))
  43                return -EFAULT;
  44        return 0;
  45}
  46
  47/*
  48 * control element info
  49 * it uses union, so the things are not easy..
  50 */
  51
  52struct snd_ctl_elem_info32 {
  53        struct snd_ctl_elem_id id; // the size of struct is same
  54        s32 type;
  55        u32 access;
  56        u32 count;
  57        s32 owner;
  58        union {
  59                struct {
  60                        s32 min;
  61                        s32 max;
  62                        s32 step;
  63                } integer;
  64                struct {
  65                        u64 min;
  66                        u64 max;
  67                        u64 step;
  68                } integer64;
  69                struct {
  70                        u32 items;
  71                        u32 item;
  72                        char name[64];
  73                        u64 names_ptr;
  74                        u32 names_length;
  75                } enumerated;
  76                unsigned char reserved[128];
  77        } value;
  78        unsigned char reserved[64];
  79} __attribute__((packed));
  80
  81static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
  82                                    struct snd_ctl_elem_info32 __user *data32)
  83{
  84        struct snd_ctl_elem_info *data;
  85        int err;
  86
  87        data = kzalloc(sizeof(*data), GFP_KERNEL);
  88        if (! data)
  89                return -ENOMEM;
  90
  91        err = -EFAULT;
  92        /* copy id */
  93        if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
  94                goto error;
  95        /* we need to copy the item index.
  96         * hope this doesn't break anything..
  97         */
  98        if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
  99                goto error;
 100
 101        err = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0);
 102        if (err < 0)
 103                goto error;
 104        err = snd_ctl_elem_info(ctl, data);
 105        if (err < 0)
 106                goto error;
 107        /* restore info to 32bit */
 108        err = -EFAULT;
 109        /* id, type, access, count */
 110        if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
 111            copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
 112                goto error;
 113        if (put_user(data->owner, &data32->owner))
 114                goto error;
 115        switch (data->type) {
 116        case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 117        case SNDRV_CTL_ELEM_TYPE_INTEGER:
 118                if (put_user(data->value.integer.min, &data32->value.integer.min) ||
 119                    put_user(data->value.integer.max, &data32->value.integer.max) ||
 120                    put_user(data->value.integer.step, &data32->value.integer.step))
 121                        goto error;
 122                break;
 123        case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 124                if (copy_to_user(&data32->value.integer64,
 125                                 &data->value.integer64,
 126                                 sizeof(data->value.integer64)))
 127                        goto error;
 128                break;
 129        case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 130                if (copy_to_user(&data32->value.enumerated,
 131                                 &data->value.enumerated,
 132                                 sizeof(data->value.enumerated)))
 133                        goto error;
 134                break;
 135        default:
 136                break;
 137        }
 138        err = 0;
 139 error:
 140        kfree(data);
 141        return err;
 142}
 143
 144/* read / write */
 145struct snd_ctl_elem_value32 {
 146        struct snd_ctl_elem_id id;
 147        unsigned int indirect;  /* bit-field causes misalignment */
 148        union {
 149                s32 integer[128];
 150                unsigned char data[512];
 151#ifndef CONFIG_X86_64
 152                s64 integer64[64];
 153#endif
 154        } value;
 155        unsigned char reserved[128];
 156};
 157
 158#ifdef CONFIG_X86_X32
 159/* x32 has a different alignment for 64bit values from ia32 */
 160struct snd_ctl_elem_value_x32 {
 161        struct snd_ctl_elem_id id;
 162        unsigned int indirect;  /* bit-field causes misalignment */
 163        union {
 164                s32 integer[128];
 165                unsigned char data[512];
 166                s64 integer64[64];
 167        } value;
 168        unsigned char reserved[128];
 169};
 170#endif /* CONFIG_X86_X32 */
 171
 172/* get the value type and count of the control */
 173static 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 -ENOENT;
 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
 202static 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
 218static int copy_ctl_value_from_user(struct snd_card *card,
 219                                    struct snd_ctl_elem_value *data,
 220                                    void __user *userdata,
 221                                    void __user *valuep,
 222                                    int *typep, int *countp)
 223{
 224        struct snd_ctl_elem_value32 __user *data32 = userdata;
 225        int i, type, size;
 226        int uninitialized_var(count);
 227        unsigned int indirect;
 228
 229        if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
 230                return -EFAULT;
 231        if (get_user(indirect, &data32->indirect))
 232                return -EFAULT;
 233        if (indirect)
 234                return -EINVAL;
 235        type = get_ctl_type(card, &data->id, &count);
 236        if (type < 0)
 237                return type;
 238
 239        if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 240            type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
 241                for (i = 0; i < count; i++) {
 242                        s32 __user *intp = valuep;
 243                        int val;
 244                        if (get_user(val, &intp[i]))
 245                                return -EFAULT;
 246                        data->value.integer.value[i] = val;
 247                }
 248        } else {
 249                size = get_elem_size(type, count);
 250                if (size < 0) {
 251                        dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
 252                        return -EINVAL;
 253                }
 254                if (copy_from_user(data->value.bytes.data, valuep, size))
 255                        return -EFAULT;
 256        }
 257
 258        *typep = type;
 259        *countp = count;
 260        return 0;
 261}
 262
 263/* restore the value to 32bit */
 264static int copy_ctl_value_to_user(void __user *userdata,
 265                                  void __user *valuep,
 266                                  struct snd_ctl_elem_value *data,
 267                                  int type, int count)
 268{
 269        int i, size;
 270
 271        if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 272            type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
 273                for (i = 0; i < count; i++) {
 274                        s32 __user *intp = valuep;
 275                        int val;
 276                        val = data->value.integer.value[i];
 277                        if (put_user(val, &intp[i]))
 278                                return -EFAULT;
 279                }
 280        } else {
 281                size = get_elem_size(type, count);
 282                if (copy_to_user(valuep, data->value.bytes.data, size))
 283                        return -EFAULT;
 284        }
 285        return 0;
 286}
 287
 288static int ctl_elem_read_user(struct snd_card *card,
 289                              void __user *userdata, void __user *valuep)
 290{
 291        struct snd_ctl_elem_value *data;
 292        int err, type, count;
 293
 294        data = kzalloc(sizeof(*data), GFP_KERNEL);
 295        if (data == NULL)
 296                return -ENOMEM;
 297
 298        err = copy_ctl_value_from_user(card, data, userdata, valuep,
 299                                       &type, &count);
 300        if (err < 0)
 301                goto error;
 302
 303        err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
 304        if (err < 0)
 305                goto error;
 306        err = snd_ctl_elem_read(card, data);
 307        if (err < 0)
 308                goto error;
 309        err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
 310 error:
 311        kfree(data);
 312        return err;
 313}
 314
 315static int ctl_elem_write_user(struct snd_ctl_file *file,
 316                               void __user *userdata, void __user *valuep)
 317{
 318        struct snd_ctl_elem_value *data;
 319        struct snd_card *card = file->card;
 320        int err, type, count;
 321
 322        data = kzalloc(sizeof(*data), GFP_KERNEL);
 323        if (data == NULL)
 324                return -ENOMEM;
 325
 326        err = copy_ctl_value_from_user(card, data, userdata, valuep,
 327                                       &type, &count);
 328        if (err < 0)
 329                goto error;
 330
 331        err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
 332        if (err < 0)
 333                goto error;
 334        err = snd_ctl_elem_write(card, file, data);
 335        if (err < 0)
 336                goto error;
 337        err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
 338 error:
 339        kfree(data);
 340        return err;
 341}
 342
 343static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 344                                         struct snd_ctl_elem_value32 __user *data32)
 345{
 346        return ctl_elem_read_user(card, data32, &data32->value);
 347}
 348
 349static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
 350                                          struct snd_ctl_elem_value32 __user *data32)
 351{
 352        return ctl_elem_write_user(file, data32, &data32->value);
 353}
 354
 355#ifdef CONFIG_X86_X32
 356static int snd_ctl_elem_read_user_x32(struct snd_card *card,
 357                                      struct snd_ctl_elem_value_x32 __user *data32)
 358{
 359        return ctl_elem_read_user(card, data32, &data32->value);
 360}
 361
 362static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
 363                                       struct snd_ctl_elem_value_x32 __user *data32)
 364{
 365        return ctl_elem_write_user(file, data32, &data32->value);
 366}
 367#endif /* CONFIG_X86_X32 */
 368
 369/* add or replace a user control */
 370static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
 371                                   struct snd_ctl_elem_info32 __user *data32,
 372                                   int replace)
 373{
 374        struct snd_ctl_elem_info *data;
 375        int err;
 376
 377        data = kzalloc(sizeof(*data), GFP_KERNEL);
 378        if (! data)
 379                return -ENOMEM;
 380
 381        err = -EFAULT;
 382        /* id, type, access, count */ \
 383        if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
 384            copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
 385                goto error;
 386        if (get_user(data->owner, &data32->owner))
 387                goto error;
 388        switch (data->type) {
 389        case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 390        case SNDRV_CTL_ELEM_TYPE_INTEGER:
 391                if (get_user(data->value.integer.min, &data32->value.integer.min) ||
 392                    get_user(data->value.integer.max, &data32->value.integer.max) ||
 393                    get_user(data->value.integer.step, &data32->value.integer.step))
 394                        goto error;
 395                break;
 396        case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 397                if (copy_from_user(&data->value.integer64,
 398                                   &data32->value.integer64,
 399                                   sizeof(data->value.integer64)))
 400                        goto error;
 401                break;
 402        case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 403                if (copy_from_user(&data->value.enumerated,
 404                                   &data32->value.enumerated,
 405                                   sizeof(data->value.enumerated)))
 406                        goto error;
 407                data->value.enumerated.names_ptr =
 408                        (uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
 409                break;
 410        default:
 411                break;
 412        }
 413        err = snd_ctl_elem_add(file, data, replace);
 414 error:
 415        kfree(data);
 416        return err;
 417}  
 418
 419enum {
 420        SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
 421        SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
 422        SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
 423        SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
 424        SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
 425        SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 426#ifdef CONFIG_X86_X32
 427        SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
 428        SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
 429#endif /* CONFIG_X86_X32 */
 430};
 431
 432static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 433{
 434        struct snd_ctl_file *ctl;
 435        struct snd_kctl_ioctl *p;
 436        void __user *argp = compat_ptr(arg);
 437        int err;
 438
 439        ctl = file->private_data;
 440        if (snd_BUG_ON(!ctl || !ctl->card))
 441                return -ENXIO;
 442
 443        switch (cmd) {
 444        case SNDRV_CTL_IOCTL_PVERSION:
 445        case SNDRV_CTL_IOCTL_CARD_INFO:
 446        case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
 447        case SNDRV_CTL_IOCTL_POWER:
 448        case SNDRV_CTL_IOCTL_POWER_STATE:
 449        case SNDRV_CTL_IOCTL_ELEM_LOCK:
 450        case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
 451        case SNDRV_CTL_IOCTL_ELEM_REMOVE:
 452        case SNDRV_CTL_IOCTL_TLV_READ:
 453        case SNDRV_CTL_IOCTL_TLV_WRITE:
 454        case SNDRV_CTL_IOCTL_TLV_COMMAND:
 455                return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
 456        case SNDRV_CTL_IOCTL_ELEM_LIST32:
 457                return snd_ctl_elem_list_compat(ctl->card, argp);
 458        case SNDRV_CTL_IOCTL_ELEM_INFO32:
 459                return snd_ctl_elem_info_compat(ctl, argp);
 460        case SNDRV_CTL_IOCTL_ELEM_READ32:
 461                return snd_ctl_elem_read_user_compat(ctl->card, argp);
 462        case SNDRV_CTL_IOCTL_ELEM_WRITE32:
 463                return snd_ctl_elem_write_user_compat(ctl, argp);
 464        case SNDRV_CTL_IOCTL_ELEM_ADD32:
 465                return snd_ctl_elem_add_compat(ctl, argp, 0);
 466        case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
 467                return snd_ctl_elem_add_compat(ctl, argp, 1);
 468#ifdef CONFIG_X86_X32
 469        case SNDRV_CTL_IOCTL_ELEM_READ_X32:
 470                return snd_ctl_elem_read_user_x32(ctl->card, argp);
 471        case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
 472                return snd_ctl_elem_write_user_x32(ctl, argp);
 473#endif /* CONFIG_X86_X32 */
 474        }
 475
 476        down_read(&snd_ioctl_rwsem);
 477        list_for_each_entry(p, &snd_control_compat_ioctls, list) {
 478                if (p->fioctl) {
 479                        err = p->fioctl(ctl->card, ctl, cmd, arg);
 480                        if (err != -ENOIOCTLCMD) {
 481                                up_read(&snd_ioctl_rwsem);
 482                                return err;
 483                        }
 484                }
 485        }
 486        up_read(&snd_ioctl_rwsem);
 487        return -ENOIOCTLCMD;
 488}
 489