control_compat.c

   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
  13 struct 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
  22 static 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
  50 struct 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
  79 static 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 */
 143 struct 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 */
 158 struct 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 */
 171 static 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
 200 static 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
 216 static 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 */
 262 static 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         struct snd_ctl_elem_value32 __user *data32 = userdata;
 268         int i, size;
 269
 270         if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 271             type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
 272                 for (i = 0; i < count; i++) {
 273                         s32 __user *intp = valuep;
 274                         int val;
 275                         val = data->value.integer.value[i];
 276                         if (put_user(val, &intp[i]))
 277                                 return -EFAULT;
 278                 }
 279         } else {
 280                 size = get_elem_size(type, count);
 281                 if (copy_to_user(valuep, data->value.bytes.data, size))
 282                         return -EFAULT;
 283         }
 284         if (copy_to_user(&data32->id, &data->id, sizeof(data32->id)))
 285                 return -EFAULT;
 286         return 0;
 287 }
 288
 289 static int ctl_elem_read_user(struct snd_card *card,
 290                               void __user *userdata, void __user *valuep)
 291 {
 292         struct snd_ctl_elem_value *data;
 293         int err, type, count;
 294
 295         data = kzalloc(sizeof(*data), GFP_KERNEL);
 296         if (data == NULL)
 297                 return -ENOMEM;
 298
 299         err = copy_ctl_value_from_user(card, data, userdata, valuep,
 300                                        &type, &count);
 301         if (err < 0)
 302                 goto error;
 303
 304         err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
 305         if (err < 0)
 306                 goto error;
 307         down_read(&card->controls_rwsem);
 308         err = snd_ctl_elem_read(card, data);
 309         up_read(&card->controls_rwsem);
 310         if (err < 0)
 311                 goto error;
 312         err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
 313  error:
 314         kfree(data);
 315         return err;
 316 }
 317
 318 static int ctl_elem_write_user(struct snd_ctl_file *file,
 319                                void __user *userdata, void __user *valuep)
 320 {
 321         struct snd_ctl_elem_value *data;
 322         struct snd_card *card = file->card;
 323         int err, type, count;
 324
 325         data = kzalloc(sizeof(*data), GFP_KERNEL);
 326         if (data == NULL)
 327                 return -ENOMEM;
 328
 329         err = copy_ctl_value_from_user(card, data, userdata, valuep,
 330                                        &type, &count);
 331         if (err < 0)
 332                 goto error;
 333
 334         err = snd_power_wait(card, SNDRV_CTL_POWER_D0);
 335         if (err < 0)
 336                 goto error;
 337         down_write(&card->controls_rwsem);
 338         err = snd_ctl_elem_write(card, file, data);
 339         up_write(&card->controls_rwsem);
 340         if (err < 0)
 341                 goto error;
 342         err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
 343  error:
 344         kfree(data);
 345         return err;
 346 }
 347
 348 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 349                                          struct snd_ctl_elem_value32 __user *data32)
 350 {
 351         return ctl_elem_read_user(card, data32, &data32->value);
 352 }
 353
 354 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
 355                                           struct snd_ctl_elem_value32 __user *data32)
 356 {
 357         return ctl_elem_write_user(file, data32, &data32->value);
 358 }
 359
 360 #ifdef CONFIG_X86_X32
 361 static int snd_ctl_elem_read_user_x32(struct snd_card *card,
 362                                       struct snd_ctl_elem_value_x32 __user *data32)
 363 {
 364         return ctl_elem_read_user(card, data32, &data32->value);
 365 }
 366
 367 static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
 368                                        struct snd_ctl_elem_value_x32 __user *data32)
 369 {
 370         return ctl_elem_write_user(file, data32, &data32->value);
 371 }
 372 #endif /* CONFIG_X86_X32 */
 373
 374 /* add or replace a user control */
 375 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
 376                                    struct snd_ctl_elem_info32 __user *data32,
 377                                    int replace)
 378 {
 379         struct snd_ctl_elem_info *data;
 380         int err;
 381
 382         data = kzalloc(sizeof(*data), GFP_KERNEL);
 383         if (! data)
 384                 return -ENOMEM;
 385
 386         err = -EFAULT;
 387         /* id, type, access, count */ \
 388         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
 389             copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
 390                 goto error;
 391         if (get_user(data->owner, &data32->owner))
 392                 goto error;
 393         switch (data->type) {
 394         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 395         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 396                 if (get_user(data->value.integer.min, &data32->value.integer.min) ||
 397                     get_user(data->value.integer.max, &data32->value.integer.max) ||
 398                     get_user(data->value.integer.step, &data32->value.integer.step))
 399                         goto error;
 400                 break;
 401         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 402                 if (copy_from_user(&data->value.integer64,
 403                                    &data32->value.integer64,
 404                                    sizeof(data->value.integer64)))
 405                         goto error;
 406                 break;
 407         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 408                 if (copy_from_user(&data->value.enumerated,
 409                                    &data32->value.enumerated,
 410                                    sizeof(data->value.enumerated)))
 411                         goto error;
 412                 data->value.enumerated.names_ptr =
 413                         (uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
 414                 break;
 415         default:
 416                 break;
 417         }
 418         err = snd_ctl_elem_add(file, data, replace);
 419  error:
 420         kfree(data);
 421         return err;
 422 }
 423
 424 enum {
 425         SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
 426         SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
 427         SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
 428         SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
 429         SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
 430         SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 431 #ifdef CONFIG_X86_X32
 432         SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
 433         SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
 434 #endif /* CONFIG_X86_X32 */
 435 };
 436
 437 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 438 {
 439         struct snd_ctl_file *ctl;
 440         struct snd_kctl_ioctl *p;
 441         void __user *argp = compat_ptr(arg);
 442         int err;
 443
 444         ctl = file->private_data;
 445         if (snd_BUG_ON(!ctl || !ctl->card))
 446                 return -ENXIO;
 447
 448         switch (cmd) {
 449         case SNDRV_CTL_IOCTL_PVERSION:
 450         case SNDRV_CTL_IOCTL_CARD_INFO:
 451         case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
 452         case SNDRV_CTL_IOCTL_POWER:
 453         case SNDRV_CTL_IOCTL_POWER_STATE:
 454         case SNDRV_CTL_IOCTL_ELEM_LOCK:
 455         case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
 456         case SNDRV_CTL_IOCTL_ELEM_REMOVE:
 457         case SNDRV_CTL_IOCTL_TLV_READ:
 458         case SNDRV_CTL_IOCTL_TLV_WRITE:
 459         case SNDRV_CTL_IOCTL_TLV_COMMAND:
 460                 return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
 461         case SNDRV_CTL_IOCTL_ELEM_LIST32:
 462                 return snd_ctl_elem_list_compat(ctl->card, argp);
 463         case SNDRV_CTL_IOCTL_ELEM_INFO32:
 464                 return snd_ctl_elem_info_compat(ctl, argp);
 465         case SNDRV_CTL_IOCTL_ELEM_READ32:
 466                 return snd_ctl_elem_read_user_compat(ctl->card, argp);
 467         case SNDRV_CTL_IOCTL_ELEM_WRITE32:
 468                 return snd_ctl_elem_write_user_compat(ctl, argp);
 469         case SNDRV_CTL_IOCTL_ELEM_ADD32:
 470                 return snd_ctl_elem_add_compat(ctl, argp, 0);
 471         case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
 472                 return snd_ctl_elem_add_compat(ctl, argp, 1);
 473 #ifdef CONFIG_X86_X32
 474         case SNDRV_CTL_IOCTL_ELEM_READ_X32:
 475                 return snd_ctl_elem_read_user_x32(ctl->card, argp);
 476         case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
 477                 return snd_ctl_elem_write_user_x32(ctl, argp);
 478 #endif /* CONFIG_X86_X32 */
 479         }
 480
 481         down_read(&snd_ioctl_rwsem);
 482         list_for_each_entry(p, &snd_control_compat_ioctls, list) {
 483                 if (p->fioctl) {
 484                         err = p->fioctl(ctl->card, ctl, cmd, arg);
 485                         if (err != -ENOIOCTLCMD) {
 486                                 up_read(&snd_ioctl_rwsem);
 487                                 return err;
 488                         }
 489                 }
 490         }
 491         up_read(&snd_ioctl_rwsem);
 492         return -ENOIOCTLCMD;
 493 }