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 } __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 __free(kfree) = NULL;
  83         int err;
  84
  85         data = kzalloc(sizeof(*data), GFP_KERNEL);
  86         if (! data)
  87                 return -ENOMEM;
  88
  89         /* copy id */
  90         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
  91                 return -EFAULT;
  92         /* we need to copy the item index.
  93          * hope this doesn't break anything..
  94          */
  95         if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
  96                 return -EFAULT;
  97
  98         err = snd_ctl_elem_info(ctl, data);
  99         if (err < 0)
 100                 return err;
 101         /* restore info to 32bit */
 102         /* id, type, access, count */
 103         if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
 104             copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
 105                 return -EFAULT;
 106         if (put_user(data->owner, &data32->owner))
 107                 return -EFAULT;
 108         switch (data->type) {
 109         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 110         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 111                 if (put_user(data->value.integer.min, &data32->value.integer.min) ||
 112                     put_user(data->value.integer.max, &data32->value.integer.max) ||
 113                     put_user(data->value.integer.step, &data32->value.integer.step))
 114                         return -EFAULT;
 115                 break;
 116         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 117                 if (copy_to_user(&data32->value.integer64,
 118                                  &data->value.integer64,
 119                                  sizeof(data->value.integer64)))
 120                         return -EFAULT;
 121                 break;
 122         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 123                 if (copy_to_user(&data32->value.enumerated,
 124                                  &data->value.enumerated,
 125                                  sizeof(data->value.enumerated)))
 126                         return -EFAULT;
 127                 break;
 128         default:
 129                 break;
 130         }
 131         return 0;
 132 }
 133
 134 /* read / write */
 135 struct snd_ctl_elem_value32 {
 136         struct snd_ctl_elem_id id;
 137         unsigned int indirect;  /* bit-field causes misalignment */
 138         union {
 139                 s32 integer[128];
 140                 unsigned char data[512];
 141 #ifndef CONFIG_X86_64
 142                 s64 integer64[64];
 143 #endif
 144         } value;
 145         unsigned char reserved[128];
 146 };
 147
 148 #ifdef CONFIG_X86_X32_ABI
 149 /* x32 has a different alignment for 64bit values from ia32 */
 150 struct snd_ctl_elem_value_x32 {
 151         struct snd_ctl_elem_id id;
 152         unsigned int indirect;  /* bit-field causes misalignment */
 153         union {
 154                 s32 integer[128];
 155                 unsigned char data[512];
 156                 s64 integer64[64];
 157         } value;
 158         unsigned char reserved[128];
 159 };
 160 #endif /* CONFIG_X86_X32_ABI */
 161
 162 /* get the value type and count of the control */
 163 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
 164                         int *countp)
 165 {
 166         struct snd_kcontrol *kctl;
 167         struct snd_ctl_elem_info *info __free(kfree) = NULL;
 168         int err;
 169
 170         guard(rwsem_read)(&card->controls_rwsem);
 171         kctl = snd_ctl_find_id_locked(card, id);
 172         if (!kctl)
 173                 return -ENOENT;
 174         info = kzalloc(sizeof(*info), GFP_KERNEL);
 175         if (info == NULL)
 176                 return -ENOMEM;
 177         info->id = *id;
 178         err = snd_power_ref_and_wait(card);
 179         if (!err)
 180                 err = kctl->info(kctl, info);
 181         snd_power_unref(card);
 182         if (err >= 0) {
 183                 err = info->type;
 184                 *countp = info->count;
 185         }
 186         return err;
 187 }
 188
 189 static int get_elem_size(snd_ctl_elem_type_t type, int count)
 190 {
 191         switch (type) {
 192         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 193                 return sizeof(s64) * count;
 194         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 195                 return sizeof(int) * count;
 196         case SNDRV_CTL_ELEM_TYPE_BYTES:
 197                 return 512;
 198         case SNDRV_CTL_ELEM_TYPE_IEC958:
 199                 return sizeof(struct snd_aes_iec958);
 200         default:
 201                 return -1;
 202         }
 203 }
 204
 205 static int copy_ctl_value_from_user(struct snd_card *card,
 206                                     struct snd_ctl_elem_value *data,
 207                                     void __user *userdata,
 208                                     void __user *valuep,
 209                                     int *typep, int *countp)
 210 {
 211         struct snd_ctl_elem_value32 __user *data32 = userdata;
 212         int i, type, size;
 213         int count;
 214         unsigned int indirect;
 215
 216         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
 217                 return -EFAULT;
 218         if (get_user(indirect, &data32->indirect))
 219                 return -EFAULT;
 220         if (indirect)
 221                 return -EINVAL;
 222         type = get_ctl_type(card, &data->id, &count);
 223         if (type < 0)
 224                 return type;
 225
 226         if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 227             type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
 228                 for (i = 0; i < count; i++) {
 229                         s32 __user *intp = valuep;
 230                         int val;
 231                         if (get_user(val, &intp[i]))
 232                                 return -EFAULT;
 233                         data->value.integer.value[i] = val;
 234                 }
 235         } else {
 236                 size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
 237                 if (size < 0) {
 238                         dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
 239                         return -EINVAL;
 240                 }
 241                 if (copy_from_user(data->value.bytes.data, valuep, size))
 242                         return -EFAULT;
 243         }
 244
 245         *typep = type;
 246         *countp = count;
 247         return 0;
 248 }
 249
 250 /* restore the value to 32bit */
 251 static int copy_ctl_value_to_user(void __user *userdata,
 252                                   void __user *valuep,
 253                                   struct snd_ctl_elem_value *data,
 254                                   int type, int count)
 255 {
 256         struct snd_ctl_elem_value32 __user *data32 = userdata;
 257         int i, size;
 258
 259         if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 260             type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) {
 261                 for (i = 0; i < count; i++) {
 262                         s32 __user *intp = valuep;
 263                         int val;
 264                         val = data->value.integer.value[i];
 265                         if (put_user(val, &intp[i]))
 266                                 return -EFAULT;
 267                 }
 268         } else {
 269                 size = get_elem_size((__force snd_ctl_elem_type_t)type, count);
 270                 if (copy_to_user(valuep, data->value.bytes.data, size))
 271                         return -EFAULT;
 272         }
 273         if (copy_to_user(&data32->id, &data->id, sizeof(data32->id)))
 274                 return -EFAULT;
 275         return 0;
 276 }
 277
 278 static int ctl_elem_read_user(struct snd_card *card,
 279                               void __user *userdata, void __user *valuep)
 280 {
 281         struct snd_ctl_elem_value *data __free(kfree) = NULL;
 282         int err, type, count;
 283
 284         data = kzalloc(sizeof(*data), GFP_KERNEL);
 285         if (data == NULL)
 286                 return -ENOMEM;
 287
 288         err = copy_ctl_value_from_user(card, data, userdata, valuep,
 289                                        &type, &count);
 290         if (err < 0)
 291                 return err;
 292
 293         err = snd_ctl_elem_read(card, data);
 294         if (err < 0)
 295                 return err;
 296         return copy_ctl_value_to_user(userdata, valuep, data, type, count);
 297 }
 298
 299 static int ctl_elem_write_user(struct snd_ctl_file *file,
 300                                void __user *userdata, void __user *valuep)
 301 {
 302         struct snd_ctl_elem_value *data __free(kfree) = NULL;
 303         struct snd_card *card = file->card;
 304         int err, type, count;
 305
 306         data = kzalloc(sizeof(*data), GFP_KERNEL);
 307         if (data == NULL)
 308                 return -ENOMEM;
 309
 310         err = copy_ctl_value_from_user(card, data, userdata, valuep,
 311                                        &type, &count);
 312         if (err < 0)
 313                 return err;
 314
 315         err = snd_ctl_elem_write(card, file, data);
 316         if (err < 0)
 317                 return err;
 318         return copy_ctl_value_to_user(userdata, valuep, data, type, count);
 319 }
 320
 321 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 322                                          struct snd_ctl_elem_value32 __user *data32)
 323 {
 324         return ctl_elem_read_user(card, data32, &data32->value);
 325 }
 326
 327 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
 328                                           struct snd_ctl_elem_value32 __user *data32)
 329 {
 330         return ctl_elem_write_user(file, data32, &data32->value);
 331 }
 332
 333 #ifdef CONFIG_X86_X32_ABI
 334 static int snd_ctl_elem_read_user_x32(struct snd_card *card,
 335                                       struct snd_ctl_elem_value_x32 __user *data32)
 336 {
 337         return ctl_elem_read_user(card, data32, &data32->value);
 338 }
 339
 340 static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file,
 341                                        struct snd_ctl_elem_value_x32 __user *data32)
 342 {
 343         return ctl_elem_write_user(file, data32, &data32->value);
 344 }
 345 #endif /* CONFIG_X86_X32_ABI */
 346
 347 /* add or replace a user control */
 348 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
 349                                    struct snd_ctl_elem_info32 __user *data32,
 350                                    int replace)
 351 {
 352         struct snd_ctl_elem_info *data __free(kfree) = NULL;
 353
 354         data = kzalloc(sizeof(*data), GFP_KERNEL);
 355         if (! data)
 356                 return -ENOMEM;
 357
 358         /* id, type, access, count */ \
 359         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
 360             copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
 361                 return -EFAULT;
 362         if (get_user(data->owner, &data32->owner))
 363                 return -EFAULT;
 364         switch (data->type) {
 365         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 366         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 367                 if (get_user(data->value.integer.min, &data32->value.integer.min) ||
 368                     get_user(data->value.integer.max, &data32->value.integer.max) ||
 369                     get_user(data->value.integer.step, &data32->value.integer.step))
 370                         return -EFAULT;
 371                 break;
 372         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 373                 if (copy_from_user(&data->value.integer64,
 374                                    &data32->value.integer64,
 375                                    sizeof(data->value.integer64)))
 376                         return -EFAULT;
 377                 break;
 378         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 379                 if (copy_from_user(&data->value.enumerated,
 380                                    &data32->value.enumerated,
 381                                    sizeof(data->value.enumerated)))
 382                         return -EFAULT;
 383                 data->value.enumerated.names_ptr =
 384                         (uintptr_t)compat_ptr(data->value.enumerated.names_ptr);
 385                 break;
 386         default:
 387                 break;
 388         }
 389         return snd_ctl_elem_add(file, data, replace);
 390 }
 391
 392 enum {
 393         SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
 394         SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
 395         SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
 396         SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
 397         SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
 398         SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 399 #ifdef CONFIG_X86_X32_ABI
 400         SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32),
 401         SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32),
 402 #endif /* CONFIG_X86_X32_ABI */
 403 };
 404
 405 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 406 {
 407         struct snd_ctl_file *ctl;
 408         struct snd_kctl_ioctl *p;
 409         void __user *argp = compat_ptr(arg);
 410         int err;
 411
 412         ctl = file->private_data;
 413         if (snd_BUG_ON(!ctl || !ctl->card))
 414                 return -ENXIO;
 415
 416         switch (cmd) {
 417         case SNDRV_CTL_IOCTL_PVERSION:
 418         case SNDRV_CTL_IOCTL_CARD_INFO:
 419         case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
 420         case SNDRV_CTL_IOCTL_POWER:
 421         case SNDRV_CTL_IOCTL_POWER_STATE:
 422         case SNDRV_CTL_IOCTL_ELEM_LOCK:
 423         case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
 424         case SNDRV_CTL_IOCTL_ELEM_REMOVE:
 425         case SNDRV_CTL_IOCTL_TLV_READ:
 426         case SNDRV_CTL_IOCTL_TLV_WRITE:
 427         case SNDRV_CTL_IOCTL_TLV_COMMAND:
 428                 return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
 429         case SNDRV_CTL_IOCTL_ELEM_LIST32:
 430                 return snd_ctl_elem_list_compat(ctl->card, argp);
 431         case SNDRV_CTL_IOCTL_ELEM_INFO32:
 432                 return snd_ctl_elem_info_compat(ctl, argp);
 433         case SNDRV_CTL_IOCTL_ELEM_READ32:
 434                 return snd_ctl_elem_read_user_compat(ctl->card, argp);
 435         case SNDRV_CTL_IOCTL_ELEM_WRITE32:
 436                 return snd_ctl_elem_write_user_compat(ctl, argp);
 437         case SNDRV_CTL_IOCTL_ELEM_ADD32:
 438                 return snd_ctl_elem_add_compat(ctl, argp, 0);
 439         case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
 440                 return snd_ctl_elem_add_compat(ctl, argp, 1);
 441 #ifdef CONFIG_X86_X32_ABI
 442         case SNDRV_CTL_IOCTL_ELEM_READ_X32:
 443                 return snd_ctl_elem_read_user_x32(ctl->card, argp);
 444         case SNDRV_CTL_IOCTL_ELEM_WRITE_X32:
 445                 return snd_ctl_elem_write_user_x32(ctl, argp);
 446 #endif /* CONFIG_X86_X32_ABI */
 447         }
 448
 449         guard(rwsem_read)(&snd_ioctl_rwsem);
 450         list_for_each_entry(p, &snd_control_compat_ioctls, list) {
 451                 if (p->fioctl) {
 452                         err = p->fioctl(ctl->card, ctl, cmd, arg);
 453                         if (err != -ENOIOCTLCMD)
 454                                 return err;
 455                 }
 456         }
 457         return -ENOIOCTLCMD;
 458 }