sound/core/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_ctl_elem_info(ctl, data);
 100         if (err < 0)
 101                 goto error;
 102         /* restore info to 32bit */
 103         err = -EFAULT;
 104         /* id, type, access, count */
 105         if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
 106             copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
 107                 goto error;
 108         if (put_user(data->owner, &data32->owner))
 109                 goto error;
 110         switch (data->type) {
 111         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 112         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 113                 if (put_user(data->value.integer.min, &data32->value.integer.min) ||
 114                     put_user(data->value.integer.max, &data32->value.integer.max) ||
 115                     put_user(data->value.integer.step, &data32->value.integer.step))
 116                         goto error;
 117                 break;
 118         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 119                 if (copy_to_user(&data32->value.integer64,
 120                                  &data->value.integer64,
 121                                  sizeof(data->value.integer64)))
 122                         goto error;
 123                 break;
 124         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 125                 if (copy_to_user(&data32->value.enumerated,
 126                                  &data->value.enumerated,
 127                                  sizeof(data->value.enumerated)))
 128                         goto error;
 129                 break;
 130         default:
 131                 break;
 132         }
 133         err = 0;
 134  error:
 135         kfree(data);
 136         return err;
 137 }
 138
 139 /* read / write */
 140 struct snd_ctl_elem_value32 {
 141         struct snd_ctl_elem_id id;
 142         unsigned int indirect;  /* bit-field causes misalignment */
 143         union {
 144                 s32 integer[128];
 145                 unsigned char data[512];
 146 #ifndef CONFIG_X86_64
 147                 s64 integer64[64];
 148 #endif
 149         } value;
 150         unsigned char reserved[128];
 151 };
 152
 153 #ifdef CONFIG_X86_X32_ABI
 154 /* x32 has a different alignment for 64bit values from ia32 */
 155 struct snd_ctl_elem_value_x32 {
 156         struct snd_ctl_elem_id id;
 157         unsigned int indirect;  /* bit-field causes misalignment */
 158         union {
 159                 s32 integer[128];
 160                 unsigned char data[512];
 161                 s64 integer64[64];
 162         } value;
 163         unsigned char reserved[128];
 164 };
 165 #endif /* CONFIG_X86_X32_ABI */
 166
 167 /* get the value type and count of the control */
 168 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
 169                         int *countp)
 170 {
 171         struct snd_kcontrol *kctl;
 172         struct snd_ctl_elem_info *info;
 173         int err;
 174
 175         down_read(&card->controls_rwsem);
 176         kctl = snd_ctl_find_id(card, id);
 177         if (! kctl) {
 178                 up_read(&card->controls_rwsem);
 179                 return -ENOENT;
 180         }
 181         info = kzalloc(sizeof(*info), GFP_KERNEL);
 182         if (info == NULL) {
 183                 up_read(&card->controls_rwsem);
 184                 return -ENOMEM;
 185         }
 186         info->id = *id;
 187         err = snd_power_ref_and_wait(card);
 188         if (!err)
 189                 err = kctl->info(kctl, info);
 190         snd_power_unref(card);
 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_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
 313 static 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_ctl_elem_write(card, file, data);
 330         if (err < 0)
 331                 goto error;
 332         err = copy_ctl_value_to_user(userdata, valuep, data, type, count);
 333  error:
 334         kfree(data);
 335         return err;
 336 }
 337
 338 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 339                                          struct snd_ctl_elem_value32 __user *data32)
 340 {
 341         return ctl_elem_read_user(card, data32, &data32->value);
 342 }
 343
 344 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
 345                                           struct snd_ctl_elem_value32 __user *data32)
 346 {
 347         return ctl_elem_write_user(file, data32, &data32->value);
 348 }
 349
 350 #ifdef CONFIG_X86_X32_ABI
 351 static int snd_ctl_elem_read_user_x32(struct snd_card *card,
 352                                       struct snd_ctl_elem_value_x32 __user *data32)
 353 {
 354         return ctl_elem_read_user(card, data32, &data32->value);
 355 }
 356
 357 static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
 358                                        struct snd_ctl_elem_value_x32 __user *data32)
 359 {
 360         return ctl_elem_write_user(file, data32, &data32->value);
 361 }
 362 #endif /* CONFIG_X86_X32_ABI */
 363
 364 /* add or replace a user control */
 365 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
 366                                    struct snd_ctl_elem_info32 __user *data32,
 367                                    int replace)
 368 {
 369         struct snd_ctl_elem_info *data;
 370         int err;
 371
 372         data = kzalloc(sizeof(*data), GFP_KERNEL);
 373         if (! data)
 374                 return -ENOMEM;
 375
 376         err = -EFAULT;
 377         /* id, type, access, count */ \
 378         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
 379             copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
 380                 goto error;
 381         if (get_user(data->owner, &data32->owner))
 382                 goto error;
 383         switch (data->type) {
 384         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 385         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 386                 if (get_user(data->value.integer.min, &data32->value.integer.min) ||
 387                     get_user(data->value.integer.max, &data32->value.integer.max) ||
 388                     get_user(data->value.integer.step, &data32->value.integer.step))
 389                         goto error;
 390                 break;
 391         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 392                 if (copy_from_user(&data->value.integer64,
 393                                    &data32->value.integer64,
 394                                    sizeof(data->value.integer64)))
 395                         goto error;
 396                 break;
 397         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 398                 if (copy_from_user(&data->value.enumerated,
 399                                    &data32->value.enumerated,
 400                                    sizeof(data->value.enumerated)))
 401                         goto error;
 402                 data->value.enumerated.names_ptr =
 403                         (uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
 404                 break;
 405         default:
 406                 break;
 407         }
 408         err = snd_ctl_elem_add(file, data, replace);
 409  error:
 410         kfree(data);
 411         return err;
 412 }
 413
 414 enum {
 415         SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
 416         SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
 417         SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
 418         SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
 419         SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
 420         SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 421 #ifdef CONFIG_X86_X32_ABI
 422         SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
 423         SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
 424 #endif /* CONFIG_X86_X32_ABI */
 425 };
 426
 427 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 428 {
 429         struct snd_ctl_file *ctl;
 430         struct snd_kctl_ioctl *p;
 431         void __user *argp = compat_ptr(arg);
 432         int err;
 433
 434         ctl = file->private_data;
 435         if (snd_BUG_ON(!ctl || !ctl->card))
 436                 return -ENXIO;
 437
 438         switch (cmd) {
 439         case SNDRV_CTL_IOCTL_PVERSION:
 440         case SNDRV_CTL_IOCTL_CARD_INFO:
 441         case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
 442         case SNDRV_CTL_IOCTL_POWER:
 443         case SNDRV_CTL_IOCTL_POWER_STATE:
 444         case SNDRV_CTL_IOCTL_ELEM_LOCK:
 445         case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
 446         case SNDRV_CTL_IOCTL_ELEM_REMOVE:
 447         case SNDRV_CTL_IOCTL_TLV_READ:
 448         case SNDRV_CTL_IOCTL_TLV_WRITE:
 449         case SNDRV_CTL_IOCTL_TLV_COMMAND:
 450                 return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
 451         case SNDRV_CTL_IOCTL_ELEM_LIST32:
 452                 return snd_ctl_elem_list_compat(ctl->card, argp);
 453         case SNDRV_CTL_IOCTL_ELEM_INFO32:
 454                 return snd_ctl_elem_info_compat(ctl, argp);
 455         case SNDRV_CTL_IOCTL_ELEM_READ32:
 456                 return snd_ctl_elem_read_user_compat(ctl->card, argp);
 457         case SNDRV_CTL_IOCTL_ELEM_WRITE32:
 458                 return snd_ctl_elem_write_user_compat(ctl, argp);
 459         case SNDRV_CTL_IOCTL_ELEM_ADD32:
 460                 return snd_ctl_elem_add_compat(ctl, argp, 0);
 461         case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
 462                 return snd_ctl_elem_add_compat(ctl, argp, 1);
 463 #ifdef CONFIG_X86_X32_ABI
 464         case SNDRV_CTL_IOCTL_ELEM_READ_X32:
 465                 return snd_ctl_elem_read_user_x32(ctl->card, argp);
 466         case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
 467                 return snd_ctl_elem_write_user_x32(ctl, argp);
 468 #endif /* CONFIG_X86_X32_ABI */
 469         }
 470
 471         down_read(&snd_ioctl_rwsem);
 472         list_for_each_entry(p, &snd_control_compat_ioctls, list) {
 473                 if (p->fioctl) {
 474                         err = p->fioctl(ctl->card, ctl, cmd, arg);
 475                         if (err != -ENOIOCTLCMD) {
 476                                 up_read(&snd_ioctl_rwsem);
 477                                 return err;
 478                         }
 479                 }
 480         }
 481         up_read(&snd_ioctl_rwsem);
 482         return -ENOIOCTLCMD;
 483 }