sound/core/control_compat.c

   1 /*
   2  * compat ioctls for control API
   3  *
   4  *   Copyright (c) by Takashi Iwai <tiwai@suse.de>
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  */
  20
  21 /* this file included from control.c */
  22
  23 #include <linux/compat.h>
  24
  25 struct snd_ctl_elem_list32 {
  26         u32 offset;
  27         u32 space;
  28         u32 used;
  29         u32 count;
  30         u32 pids;
  31         unsigned char reserved[50];
  32 } /* don't set packed attribute here */;
  33
  34 static int snd_ctl_elem_list_compat(struct snd_card *card,
  35                                     struct snd_ctl_elem_list32 __user *data32)
  36 {
  37         struct snd_ctl_elem_list __user *data;
  38         compat_caddr_t ptr;
  39         int err;
  40
  41         data = compat_alloc_user_space(sizeof(*data));
  42
  43         /* offset, space, used, count */
  44         if (copy_in_user(data, data32, 4 * sizeof(u32)))
  45                 return -EFAULT;
  46         /* pids */
  47         if (get_user(ptr, &data32->pids) ||
  48             put_user(compat_ptr(ptr), &data->pids))
  49                 return -EFAULT;
  50         err = snd_ctl_elem_list(card, data);
  51         if (err < 0)
  52                 return err;
  53         /* copy the result */
  54         if (copy_in_user(data32, data, 4 * sizeof(u32)))
  55                 return -EFAULT;
  56         return 0;
  57 }
  58
  59 /*
  60  * control element info
  61  * it uses union, so the things are not easy..
  62  */
  63
  64 struct snd_ctl_elem_info32 {
  65         struct snd_ctl_elem_id id; // the size of struct is same
  66         s32 type;
  67         u32 access;
  68         u32 count;
  69         s32 owner;
  70         union {
  71                 struct {
  72                         s32 min;
  73                         s32 max;
  74                         s32 step;
  75                 } integer;
  76                 struct {
  77                         u64 min;
  78                         u64 max;
  79                         u64 step;
  80                 } integer64;
  81                 struct {
  82                         u32 items;
  83                         u32 item;
  84                         char name[64];
  85                 } enumerated;
  86                 unsigned char reserved[128];
  87         } value;
  88         unsigned char reserved[64];
  89 } __attribute__((packed));
  90
  91 static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
  92                                     struct snd_ctl_elem_info32 __user *data32)
  93 {
  94         struct snd_ctl_elem_info *data;
  95         int err;
  96
  97         data = kzalloc(sizeof(*data), GFP_KERNEL);
  98         if (! data)
  99                 return -ENOMEM;
 100
 101         err = -EFAULT;
 102         /* copy id */
 103         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
 104                 goto error;
 105         /* we need to copy the item index.
 106          * hope this doesn't break anything..
 107          */
 108         if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
 109                 goto error;
 110         err = snd_ctl_elem_info(ctl, data);
 111         if (err < 0)
 112                 goto error;
 113         /* restore info to 32bit */
 114         err = -EFAULT;
 115         /* id, type, access, count */
 116         if (copy_to_user(&data32->id, &data->id, sizeof(data->id)) ||
 117             copy_to_user(&data32->type, &data->type, 3 * sizeof(u32)))
 118                 goto error;
 119         if (put_user(data->owner, &data32->owner))
 120                 goto error;
 121         switch (data->type) {
 122         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 123         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 124                 if (put_user(data->value.integer.min, &data32->value.integer.min) ||
 125                     put_user(data->value.integer.max, &data32->value.integer.max) ||
 126                     put_user(data->value.integer.step, &data32->value.integer.step))
 127                         goto error;
 128                 break;
 129         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 130                 if (copy_to_user(&data32->value.integer64,
 131                                  &data->value.integer64,
 132                                  sizeof(data->value.integer64)))
 133                         goto error;
 134                 break;
 135         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 136                 if (copy_to_user(&data32->value.enumerated,
 137                                  &data->value.enumerated,
 138                                  sizeof(data->value.enumerated)))
 139                         goto error;
 140                 break;
 141         default:
 142                 break;
 143         }
 144         err = 0;
 145  error:
 146         kfree(data);
 147         return err;
 148 }
 149
 150 /* read / write */
 151 struct snd_ctl_elem_value32 {
 152         struct snd_ctl_elem_id id;
 153         unsigned int indirect;  /* bit-field causes misalignment */
 154         union {
 155                 s32 integer[128];
 156                 unsigned char data[512];
 157 #ifndef CONFIG_X86_64
 158                 s64 integer64[64];
 159 #endif
 160         } value;
 161         unsigned char reserved[128];
 162 };
 163
 164
 165 /* get the value type and count of the control */
 166 static int get_ctl_type(struct snd_card *card, struct snd_ctl_elem_id *id,
 167                         int *countp)
 168 {
 169         struct snd_kcontrol *kctl;
 170         struct snd_ctl_elem_info *info;
 171         int err;
 172
 173         down_read(&card->controls_rwsem);
 174         kctl = snd_ctl_find_id(card, id);
 175         if (! kctl) {
 176                 up_read(&card->controls_rwsem);
 177                 return -ENXIO;
 178         }
 179         info = kzalloc(sizeof(*info), GFP_KERNEL);
 180         if (info == NULL) {
 181                 up_read(&card->controls_rwsem);
 182                 return -ENOMEM;
 183         }
 184         info->id = *id;
 185         err = kctl->info(kctl, info);
 186         up_read(&card->controls_rwsem);
 187         if (err >= 0) {
 188                 err = info->type;
 189                 *countp = info->count;
 190         }
 191         kfree(info);
 192         return err;
 193 }
 194
 195 static int get_elem_size(int type, int count)
 196 {
 197         switch (type) {
 198         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 199                 return sizeof(s64) * count;
 200         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 201                 return sizeof(int) * count;
 202         case SNDRV_CTL_ELEM_TYPE_BYTES:
 203                 return 512;
 204         case SNDRV_CTL_ELEM_TYPE_IEC958:
 205                 return sizeof(struct snd_aes_iec958);
 206         default:
 207                 return -1;
 208         }
 209 }
 210
 211 static int copy_ctl_value_from_user(struct snd_card *card,
 212                                     struct snd_ctl_elem_value *data,
 213                                     struct snd_ctl_elem_value32 __user *data32,
 214                                     int *typep, int *countp)
 215 {
 216         int i, type, count, size;
 217         unsigned int indirect;
 218
 219         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)))
 220                 return -EFAULT;
 221         if (get_user(indirect, &data32->indirect))
 222                 return -EFAULT;
 223         if (indirect)
 224                 return -EINVAL;
 225         type = get_ctl_type(card, &data->id, &count);
 226         if (type < 0)
 227                 return type;
 228
 229         if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 230             type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
 231                 for (i = 0; i < count; i++) {
 232                         int val;
 233                         if (get_user(val, &data32->value.integer[i]))
 234                                 return -EFAULT;
 235                         data->value.integer.value[i] = val;
 236                 }
 237         } else {
 238                 size = get_elem_size(type, count);
 239                 if (size < 0) {
 240                         printk(KERN_ERR "snd_ioctl32_ctl_elem_value: unknown type %d\n", type);
 241                         return -EINVAL;
 242                 }
 243                 if (copy_from_user(data->value.bytes.data,
 244                                    data32->value.data, size))
 245                         return -EFAULT;
 246         }
 247
 248         *typep = type;
 249         *countp = count;
 250         return 0;
 251 }
 252
 253 /* restore the value to 32bit */
 254 static int copy_ctl_value_to_user(struct snd_ctl_elem_value32 __user *data32,
 255                                   struct snd_ctl_elem_value *data,
 256                                   int type, int count)
 257 {
 258         int i, size;
 259
 260         if (type == SNDRV_CTL_ELEM_TYPE_BOOLEAN ||
 261             type == SNDRV_CTL_ELEM_TYPE_INTEGER) {
 262                 for (i = 0; i < count; i++) {
 263                         int val;
 264                         val = data->value.integer.value[i];
 265                         if (put_user(val, &data32->value.integer[i]))
 266                                 return -EFAULT;
 267                 }
 268         } else {
 269                 size = get_elem_size(type, count);
 270                 if (copy_to_user(data32->value.data,
 271                                  data->value.bytes.data, size))
 272                         return -EFAULT;
 273         }
 274         return 0;
 275 }
 276
 277 static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 278                                          struct snd_ctl_elem_value32 __user *data32)
 279 {
 280         struct snd_ctl_elem_value *data;
 281         int err, type, count;
 282
 283         data = kzalloc(sizeof(*data), GFP_KERNEL);
 284         if (data == NULL)
 285                 return -ENOMEM;
 286
 287         if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
 288                 goto error;
 289         if ((err = snd_ctl_elem_read(card, data)) < 0)
 290                 goto error;
 291         err = copy_ctl_value_to_user(data32, data, type, count);
 292  error:
 293         kfree(data);
 294         return err;
 295 }
 296
 297 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
 298                                           struct snd_ctl_elem_value32 __user *data32)
 299 {
 300         struct snd_ctl_elem_value *data;
 301         int err, type, count;
 302
 303         data = kzalloc(sizeof(*data), GFP_KERNEL);
 304         if (data == NULL)
 305                 return -ENOMEM;
 306
 307         if ((err = copy_ctl_value_from_user(file->card, data, data32, &type, &count)) < 0)
 308                 goto error;
 309         if ((err = snd_ctl_elem_write(file->card, file, data)) < 0)
 310                 goto error;
 311         err = copy_ctl_value_to_user(data32, data, type, count);
 312  error:
 313         kfree(data);
 314         return err;
 315 }
 316
 317 /* add or replace a user control */
 318 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file,
 319                                    struct snd_ctl_elem_info32 __user *data32,
 320                                    int replace)
 321 {
 322         struct snd_ctl_elem_info *data;
 323         int err;
 324
 325         data = kzalloc(sizeof(*data), GFP_KERNEL);
 326         if (! data)
 327                 return -ENOMEM;
 328
 329         err = -EFAULT;
 330         /* id, type, access, count */ \
 331         if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) ||
 332             copy_from_user(&data->type, &data32->type, 3 * sizeof(u32)))
 333                 goto error;
 334         if (get_user(data->owner, &data32->owner) ||
 335             get_user(data->type, &data32->type))
 336                 goto error;
 337         switch (data->type) {
 338         case SNDRV_CTL_ELEM_TYPE_BOOLEAN:
 339         case SNDRV_CTL_ELEM_TYPE_INTEGER:
 340                 if (get_user(data->value.integer.min, &data32->value.integer.min) ||
 341                     get_user(data->value.integer.max, &data32->value.integer.max) ||
 342                     get_user(data->value.integer.step, &data32->value.integer.step))
 343                         goto error;
 344                 break;
 345         case SNDRV_CTL_ELEM_TYPE_INTEGER64:
 346                 if (copy_from_user(&data->value.integer64,
 347                                    &data32->value.integer64,
 348                                    sizeof(data->value.integer64)))
 349                         goto error;
 350                 break;
 351         case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
 352                 if (copy_from_user(&data->value.enumerated,
 353                                    &data32->value.enumerated,
 354                                    sizeof(data->value.enumerated)))
 355                         goto error;
 356                 break;
 357         default:
 358                 break;
 359         }
 360         err = snd_ctl_elem_add(file, data, replace);
 361  error:
 362         kfree(data);
 363         return err;
 364 }
 365
 366 enum {
 367         SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32),
 368         SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32),
 369         SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32),
 370         SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32),
 371         SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32),
 372         SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32),
 373 };
 374
 375 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg)
 376 {
 377         struct snd_ctl_file *ctl;
 378         struct list_head *list;
 379         void __user *argp = compat_ptr(arg);
 380         int err;
 381
 382         ctl = file->private_data;
 383         snd_assert(ctl && ctl->card, return -ENXIO);
 384
 385         switch (cmd) {
 386         case SNDRV_CTL_IOCTL_PVERSION:
 387         case SNDRV_CTL_IOCTL_CARD_INFO:
 388         case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS:
 389         case SNDRV_CTL_IOCTL_POWER:
 390         case SNDRV_CTL_IOCTL_POWER_STATE:
 391         case SNDRV_CTL_IOCTL_ELEM_LOCK:
 392         case SNDRV_CTL_IOCTL_ELEM_UNLOCK:
 393                 return snd_ctl_ioctl(file, cmd, (unsigned long)argp);
 394         case SNDRV_CTL_IOCTL_ELEM_LIST32:
 395                 return snd_ctl_elem_list_compat(ctl->card, argp);
 396         case SNDRV_CTL_IOCTL_ELEM_INFO32:
 397                 return snd_ctl_elem_info_compat(ctl, argp);
 398         case SNDRV_CTL_IOCTL_ELEM_READ32:
 399                 return snd_ctl_elem_read_user_compat(ctl->card, argp);
 400         case SNDRV_CTL_IOCTL_ELEM_WRITE32:
 401                 return snd_ctl_elem_write_user_compat(ctl, argp);
 402         case SNDRV_CTL_IOCTL_ELEM_ADD32:
 403                 return snd_ctl_elem_add_compat(ctl, argp, 0);
 404         case SNDRV_CTL_IOCTL_ELEM_REPLACE32:
 405                 return snd_ctl_elem_add_compat(ctl, argp, 1);
 406         }
 407
 408         down_read(&snd_ioctl_rwsem);
 409         list_for_each(list, &snd_control_compat_ioctls) {
 410                 struct snd_kctl_ioctl *p = list_entry(list, struct snd_kctl_ioctl, list);
 411                 if (p->fioctl) {
 412                         err = p->fioctl(ctl->card, ctl, cmd, arg);
 413                         if (err != -ENOIOCTLCMD) {
 414                                 up_read(&snd_ioctl_rwsem);
 415                                 return err;
 416                         }
 417                 }
 418         }
 419         up_read(&snd_ioctl_rwsem);
 420         return -ENOIOCTLCMD;
 421 }