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(snd_ctl_elem_type_t 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 == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN || 238 type == (__force int)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((__force snd_ctl_elem_type_t)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 == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN || 271 type == (__force int)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((__force snd_ctl_elem_type_t)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 } 484