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_card *card = ctl->card; 83 int err; 84 struct snd_ctl_elem_info *data __free(kfree) = 85 kzalloc_obj(*data, GFP_KERNEL); 86 87 if (! data) 88 return -ENOMEM; 89 90 /* copy id */ 91 if (copy_from_user(&data->id, &data32->id, sizeof(data->id))) 92 return -EFAULT; 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 return -EFAULT; 98 99 err = snd_power_ref_and_wait(card); 100 if (err < 0) 101 return err; 102 err = snd_ctl_elem_info(ctl, data); 103 snd_power_unref(card); 104 if (err < 0) 105 return err; 106 /* restore info to 32bit */ 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 return -EFAULT; 111 if (put_user(data->owner, &data32->owner)) 112 return -EFAULT; 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 return -EFAULT; 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 return -EFAULT; 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 return -EFAULT; 132 break; 133 default: 134 break; 135 } 136 return 0; 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 int err; 173 174 guard(rwsem_read)(&card->controls_rwsem); 175 kctl = snd_ctl_find_id(card, id); 176 if (!kctl) 177 return -ENOENT; 178 179 struct snd_ctl_elem_info *info __free(kfree) = 180 kzalloc_obj(*info, GFP_KERNEL); 181 if (info == NULL) 182 return -ENOMEM; 183 info->id = *id; 184 err = kctl->info(kctl, info); 185 if (err >= 0) { 186 err = info->type; 187 *countp = info->count; 188 } 189 return err; 190 } 191 192 static int get_elem_size(snd_ctl_elem_type_t type, int count) 193 { 194 switch (type) { 195 case SNDRV_CTL_ELEM_TYPE_INTEGER64: 196 return sizeof(s64) * count; 197 case SNDRV_CTL_ELEM_TYPE_ENUMERATED: 198 return sizeof(int) * count; 199 case SNDRV_CTL_ELEM_TYPE_BYTES: 200 return 512; 201 case SNDRV_CTL_ELEM_TYPE_IEC958: 202 return sizeof(struct snd_aes_iec958); 203 default: 204 return -1; 205 } 206 } 207 208 static int copy_ctl_value_from_user(struct snd_card *card, 209 struct snd_ctl_elem_value *data, 210 void __user *userdata, 211 void __user *valuep, 212 int *typep, int *countp) 213 { 214 struct snd_ctl_elem_value32 __user *data32 = userdata; 215 int i, type, size; 216 int count; 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 == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN || 230 type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) { 231 for (i = 0; i < count; i++) { 232 s32 __user *intp = valuep; 233 int val; 234 if (get_user(val, &intp[i])) 235 return -EFAULT; 236 data->value.integer.value[i] = val; 237 } 238 } else { 239 size = get_elem_size((__force snd_ctl_elem_type_t)type, count); 240 if (size < 0) { 241 dev_err(card->dev, "snd_ioctl32_ctl_elem_value: unknown type %d\n", type); 242 return -EINVAL; 243 } 244 if (copy_from_user(data->value.bytes.data, valuep, 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(void __user *userdata, 255 void __user *valuep, 256 struct snd_ctl_elem_value *data, 257 int type, int count) 258 { 259 struct snd_ctl_elem_value32 __user *data32 = userdata; 260 int i, size; 261 262 if (type == (__force int)SNDRV_CTL_ELEM_TYPE_BOOLEAN || 263 type == (__force int)SNDRV_CTL_ELEM_TYPE_INTEGER) { 264 for (i = 0; i < count; i++) { 265 s32 __user *intp = valuep; 266 int val; 267 val = data->value.integer.value[i]; 268 if (put_user(val, &intp[i])) 269 return -EFAULT; 270 } 271 } else { 272 size = get_elem_size((__force snd_ctl_elem_type_t)type, count); 273 if (copy_to_user(valuep, data->value.bytes.data, size)) 274 return -EFAULT; 275 } 276 if (copy_to_user(&data32->id, &data->id, sizeof(data32->id))) 277 return -EFAULT; 278 return 0; 279 } 280 281 static int __ctl_elem_read_user(struct snd_card *card, 282 void __user *userdata, void __user *valuep) 283 { 284 int err, type, count; 285 struct snd_ctl_elem_value *data __free(kfree) = 286 kzalloc_obj(*data, GFP_KERNEL); 287 288 if (data == NULL) 289 return -ENOMEM; 290 291 err = copy_ctl_value_from_user(card, data, userdata, valuep, 292 &type, &count); 293 if (err < 0) 294 return err; 295 296 err = snd_ctl_elem_read(card, data); 297 if (err < 0) 298 return err; 299 return copy_ctl_value_to_user(userdata, valuep, data, type, count); 300 } 301 302 static int ctl_elem_read_user(struct snd_card *card, 303 void __user *userdata, void __user *valuep) 304 { 305 int err; 306 307 err = snd_power_ref_and_wait(card); 308 if (err < 0) 309 return err; 310 err = __ctl_elem_read_user(card, userdata, valuep); 311 snd_power_unref(card); 312 return err; 313 } 314 315 static int __ctl_elem_write_user(struct snd_ctl_file *file, 316 void __user *userdata, void __user *valuep) 317 { 318 struct snd_card *card = file->card; 319 int err, type, count; 320 struct snd_ctl_elem_value *data __free(kfree) = 321 kzalloc_obj(*data, GFP_KERNEL); 322 323 if (data == NULL) 324 return -ENOMEM; 325 326 err = copy_ctl_value_from_user(card, data, userdata, valuep, 327 &type, &count); 328 if (err < 0) 329 return err; 330 331 err = snd_ctl_elem_write(card, file, data); 332 if (err < 0) 333 return err; 334 return copy_ctl_value_to_user(userdata, valuep, data, type, count); 335 } 336 337 static int ctl_elem_write_user(struct snd_ctl_file *file, 338 void __user *userdata, void __user *valuep) 339 { 340 struct snd_card *card = file->card; 341 int err; 342 343 err = snd_power_ref_and_wait(card); 344 if (err < 0) 345 return err; 346 err = __ctl_elem_write_user(file, userdata, valuep); 347 snd_power_unref(card); 348 return err; 349 } 350 351 static int snd_ctl_elem_read_user_compat(struct snd_card *card, 352 struct snd_ctl_elem_value32 __user *data32) 353 { 354 return ctl_elem_read_user(card, data32, &data32->value); 355 } 356 357 static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file, 358 struct snd_ctl_elem_value32 __user *data32) 359 { 360 return ctl_elem_write_user(file, data32, &data32->value); 361 } 362 363 #ifdef CONFIG_X86_X32_ABI 364 static int snd_ctl_elem_read_user_x32(struct snd_card *card, 365 struct snd_ctl_elem_value_x32 __user *data32) 366 { 367 return ctl_elem_read_user(card, data32, &data32->value); 368 } 369 370 static int snd_ctl_elem_write_user_x32(struct snd_ctl_file *file, 371 struct snd_ctl_elem_value_x32 __user *data32) 372 { 373 return ctl_elem_write_user(file, data32, &data32->value); 374 } 375 #endif /* CONFIG_X86_X32_ABI */ 376 377 /* add or replace a user control */ 378 static int snd_ctl_elem_add_compat(struct snd_ctl_file *file, 379 struct snd_ctl_elem_info32 __user *data32, 380 int replace) 381 { 382 struct snd_ctl_elem_info *data __free(kfree) = 383 kzalloc_obj(*data, GFP_KERNEL); 384 385 if (! data) 386 return -ENOMEM; 387 388 /* id, type, access, count */ \ 389 if (copy_from_user(&data->id, &data32->id, sizeof(data->id)) || 390 copy_from_user(&data->type, &data32->type, 3 * sizeof(u32))) 391 return -EFAULT; 392 if (get_user(data->owner, &data32->owner)) 393 return -EFAULT; 394 switch (data->type) { 395 case SNDRV_CTL_ELEM_TYPE_BOOLEAN: 396 case SNDRV_CTL_ELEM_TYPE_INTEGER: 397 if (get_user(data->value.integer.min, &data32->value.integer.min) || 398 get_user(data->value.integer.max, &data32->value.integer.max) || 399 get_user(data->value.integer.step, &data32->value.integer.step)) 400 return -EFAULT; 401 break; 402 case SNDRV_CTL_ELEM_TYPE_INTEGER64: 403 if (copy_from_user(&data->value.integer64, 404 &data32->value.integer64, 405 sizeof(data->value.integer64))) 406 return -EFAULT; 407 break; 408 case SNDRV_CTL_ELEM_TYPE_ENUMERATED: 409 if (copy_from_user(&data->value.enumerated, 410 &data32->value.enumerated, 411 sizeof(data->value.enumerated))) 412 return -EFAULT; 413 data->value.enumerated.names_ptr = 414 (uintptr_t)compat_ptr(data->value.enumerated.names_ptr); 415 break; 416 default: 417 break; 418 } 419 return snd_ctl_elem_add(file, data, replace); 420 } 421 422 enum { 423 SNDRV_CTL_IOCTL_ELEM_LIST32 = _IOWR('U', 0x10, struct snd_ctl_elem_list32), 424 SNDRV_CTL_IOCTL_ELEM_INFO32 = _IOWR('U', 0x11, struct snd_ctl_elem_info32), 425 SNDRV_CTL_IOCTL_ELEM_READ32 = _IOWR('U', 0x12, struct snd_ctl_elem_value32), 426 SNDRV_CTL_IOCTL_ELEM_WRITE32 = _IOWR('U', 0x13, struct snd_ctl_elem_value32), 427 SNDRV_CTL_IOCTL_ELEM_ADD32 = _IOWR('U', 0x17, struct snd_ctl_elem_info32), 428 SNDRV_CTL_IOCTL_ELEM_REPLACE32 = _IOWR('U', 0x18, struct snd_ctl_elem_info32), 429 #ifdef CONFIG_X86_X32_ABI 430 SNDRV_CTL_IOCTL_ELEM_READ_X32 = _IOWR('U', 0x12, struct snd_ctl_elem_value_x32), 431 SNDRV_CTL_IOCTL_ELEM_WRITE_X32 = _IOWR('U', 0x13, struct snd_ctl_elem_value_x32), 432 #endif /* CONFIG_X86_X32_ABI */ 433 }; 434 435 static inline long snd_ctl_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg) 436 { 437 struct snd_ctl_file *ctl; 438 struct snd_kctl_ioctl *p; 439 void __user *argp = compat_ptr(arg); 440 int err; 441 442 ctl = file->private_data; 443 if (snd_BUG_ON(!ctl || !ctl->card)) 444 return -ENXIO; 445 446 switch (cmd) { 447 case SNDRV_CTL_IOCTL_PVERSION: 448 case SNDRV_CTL_IOCTL_CARD_INFO: 449 case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS: 450 case SNDRV_CTL_IOCTL_POWER: 451 case SNDRV_CTL_IOCTL_POWER_STATE: 452 case SNDRV_CTL_IOCTL_ELEM_LOCK: 453 case SNDRV_CTL_IOCTL_ELEM_UNLOCK: 454 case SNDRV_CTL_IOCTL_ELEM_REMOVE: 455 case SNDRV_CTL_IOCTL_TLV_READ: 456 case SNDRV_CTL_IOCTL_TLV_WRITE: 457 case SNDRV_CTL_IOCTL_TLV_COMMAND: 458 return snd_ctl_ioctl(file, cmd, (unsigned long)argp); 459 case SNDRV_CTL_IOCTL_ELEM_LIST32: 460 return snd_ctl_elem_list_compat(ctl->card, argp); 461 case SNDRV_CTL_IOCTL_ELEM_INFO32: 462 return snd_ctl_elem_info_compat(ctl, argp); 463 case SNDRV_CTL_IOCTL_ELEM_READ32: 464 return snd_ctl_elem_read_user_compat(ctl->card, argp); 465 case SNDRV_CTL_IOCTL_ELEM_WRITE32: 466 return snd_ctl_elem_write_user_compat(ctl, argp); 467 case SNDRV_CTL_IOCTL_ELEM_ADD32: 468 return snd_ctl_elem_add_compat(ctl, argp, 0); 469 case SNDRV_CTL_IOCTL_ELEM_REPLACE32: 470 return snd_ctl_elem_add_compat(ctl, argp, 1); 471 #ifdef CONFIG_X86_X32_ABI 472 case SNDRV_CTL_IOCTL_ELEM_READ_X32: 473 return snd_ctl_elem_read_user_x32(ctl->card, argp); 474 case SNDRV_CTL_IOCTL_ELEM_WRITE_X32: 475 return snd_ctl_elem_write_user_x32(ctl, argp); 476 #endif /* CONFIG_X86_X32_ABI */ 477 } 478 479 guard(rwsem_read)(&snd_ioctl_rwsem); 480 list_for_each_entry(p, &snd_control_compat_ioctls, list) { 481 if (p->fioctl) { 482 err = p->fioctl(ctl->card, ctl, cmd, arg); 483 if (err != -ENOIOCTLCMD) 484 return err; 485 } 486 } 487 return -ENOIOCTLCMD; 488 } 489