1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/capability.h> 3 #include <linux/blkdev.h> 4 #include <linux/export.h> 5 #include <linux/gfp.h> 6 #include <linux/blkpg.h> 7 #include <linux/hdreg.h> 8 #include <linux/backing-dev.h> 9 #include <linux/fs.h> 10 #include <linux/blktrace_api.h> 11 #include <linux/pr.h> 12 #include <linux/uaccess.h> 13 14 static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) 15 { 16 struct block_device *bdevp; 17 struct gendisk *disk; 18 struct hd_struct *part, *lpart; 19 struct blkpg_ioctl_arg a; 20 struct blkpg_partition p; 21 struct disk_part_iter piter; 22 long long start, length; 23 int partno; 24 25 if (!capable(CAP_SYS_ADMIN)) 26 return -EACCES; 27 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg))) 28 return -EFAULT; 29 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition))) 30 return -EFAULT; 31 disk = bdev->bd_disk; 32 if (bdev != bdev->bd_contains) 33 return -EINVAL; 34 partno = p.pno; 35 if (partno <= 0) 36 return -EINVAL; 37 switch (a.op) { 38 case BLKPG_ADD_PARTITION: 39 start = p.start >> 9; 40 length = p.length >> 9; 41 /* check for fit in a hd_struct */ 42 if (sizeof(sector_t) == sizeof(long) && 43 sizeof(long long) > sizeof(long)) { 44 long pstart = start, plength = length; 45 if (pstart != start || plength != length 46 || pstart < 0 || plength < 0 || partno > 65535) 47 return -EINVAL; 48 } 49 /* check if partition is aligned to blocksize */ 50 if (p.start & (bdev_logical_block_size(bdev) - 1)) 51 return -EINVAL; 52 53 mutex_lock(&bdev->bd_mutex); 54 55 /* overlap? */ 56 disk_part_iter_init(&piter, disk, 57 DISK_PITER_INCL_EMPTY); 58 while ((part = disk_part_iter_next(&piter))) { 59 if (!(start + length <= part->start_sect || 60 start >= part->start_sect + part->nr_sects)) { 61 disk_part_iter_exit(&piter); 62 mutex_unlock(&bdev->bd_mutex); 63 return -EBUSY; 64 } 65 } 66 disk_part_iter_exit(&piter); 67 68 /* all seems OK */ 69 part = add_partition(disk, partno, start, length, 70 ADDPART_FLAG_NONE, NULL); 71 mutex_unlock(&bdev->bd_mutex); 72 return PTR_ERR_OR_ZERO(part); 73 case BLKPG_DEL_PARTITION: 74 part = disk_get_part(disk, partno); 75 if (!part) 76 return -ENXIO; 77 78 bdevp = bdget(part_devt(part)); 79 disk_put_part(part); 80 if (!bdevp) 81 return -ENOMEM; 82 83 mutex_lock(&bdevp->bd_mutex); 84 if (bdevp->bd_openers) { 85 mutex_unlock(&bdevp->bd_mutex); 86 bdput(bdevp); 87 return -EBUSY; 88 } 89 /* all seems OK */ 90 fsync_bdev(bdevp); 91 invalidate_bdev(bdevp); 92 93 mutex_lock_nested(&bdev->bd_mutex, 1); 94 delete_partition(disk, partno); 95 mutex_unlock(&bdev->bd_mutex); 96 mutex_unlock(&bdevp->bd_mutex); 97 bdput(bdevp); 98 99 return 0; 100 case BLKPG_RESIZE_PARTITION: 101 start = p.start >> 9; 102 /* new length of partition in bytes */ 103 length = p.length >> 9; 104 /* check for fit in a hd_struct */ 105 if (sizeof(sector_t) == sizeof(long) && 106 sizeof(long long) > sizeof(long)) { 107 long pstart = start, plength = length; 108 if (pstart != start || plength != length 109 || pstart < 0 || plength < 0) 110 return -EINVAL; 111 } 112 part = disk_get_part(disk, partno); 113 if (!part) 114 return -ENXIO; 115 bdevp = bdget(part_devt(part)); 116 if (!bdevp) { 117 disk_put_part(part); 118 return -ENOMEM; 119 } 120 mutex_lock(&bdevp->bd_mutex); 121 mutex_lock_nested(&bdev->bd_mutex, 1); 122 if (start != part->start_sect) { 123 mutex_unlock(&bdevp->bd_mutex); 124 mutex_unlock(&bdev->bd_mutex); 125 bdput(bdevp); 126 disk_put_part(part); 127 return -EINVAL; 128 } 129 /* overlap? */ 130 disk_part_iter_init(&piter, disk, 131 DISK_PITER_INCL_EMPTY); 132 while ((lpart = disk_part_iter_next(&piter))) { 133 if (lpart->partno != partno && 134 !(start + length <= lpart->start_sect || 135 start >= lpart->start_sect + lpart->nr_sects) 136 ) { 137 disk_part_iter_exit(&piter); 138 mutex_unlock(&bdevp->bd_mutex); 139 mutex_unlock(&bdev->bd_mutex); 140 bdput(bdevp); 141 disk_put_part(part); 142 return -EBUSY; 143 } 144 } 145 disk_part_iter_exit(&piter); 146 part_nr_sects_write(part, (sector_t)length); 147 i_size_write(bdevp->bd_inode, p.length); 148 mutex_unlock(&bdevp->bd_mutex); 149 mutex_unlock(&bdev->bd_mutex); 150 bdput(bdevp); 151 disk_put_part(part); 152 return 0; 153 default: 154 return -EINVAL; 155 } 156 } 157 158 /* 159 * This is an exported API for the block driver, and will not 160 * acquire bd_mutex. This API should be used in case that 161 * caller has held bd_mutex already. 162 */ 163 int __blkdev_reread_part(struct block_device *bdev) 164 { 165 struct gendisk *disk = bdev->bd_disk; 166 167 if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains) 168 return -EINVAL; 169 if (!capable(CAP_SYS_ADMIN)) 170 return -EACCES; 171 172 lockdep_assert_held(&bdev->bd_mutex); 173 174 return rescan_partitions(disk, bdev); 175 } 176 EXPORT_SYMBOL(__blkdev_reread_part); 177 178 /* 179 * This is an exported API for the block driver, and will 180 * try to acquire bd_mutex. If bd_mutex has been held already 181 * in current context, please call __blkdev_reread_part(). 182 * 183 * Make sure the held locks in current context aren't required 184 * in open()/close() handler and I/O path for avoiding ABBA deadlock: 185 * - bd_mutex is held before calling block driver's open/close 186 * handler 187 * - reading partition table may submit I/O to the block device 188 */ 189 int blkdev_reread_part(struct block_device *bdev) 190 { 191 int res; 192 193 mutex_lock(&bdev->bd_mutex); 194 res = __blkdev_reread_part(bdev); 195 mutex_unlock(&bdev->bd_mutex); 196 197 return res; 198 } 199 EXPORT_SYMBOL(blkdev_reread_part); 200 201 static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, 202 unsigned long arg, unsigned long flags) 203 { 204 uint64_t range[2]; 205 uint64_t start, len; 206 struct request_queue *q = bdev_get_queue(bdev); 207 struct address_space *mapping = bdev->bd_inode->i_mapping; 208 209 210 if (!(mode & FMODE_WRITE)) 211 return -EBADF; 212 213 if (!blk_queue_discard(q)) 214 return -EOPNOTSUPP; 215 216 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 217 return -EFAULT; 218 219 start = range[0]; 220 len = range[1]; 221 222 if (start & 511) 223 return -EINVAL; 224 if (len & 511) 225 return -EINVAL; 226 227 if (start + len > i_size_read(bdev->bd_inode)) 228 return -EINVAL; 229 truncate_inode_pages_range(mapping, start, start + len - 1); 230 return blkdev_issue_discard(bdev, start >> 9, len >> 9, 231 GFP_KERNEL, flags); 232 } 233 234 static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode, 235 unsigned long arg) 236 { 237 uint64_t range[2]; 238 struct address_space *mapping; 239 uint64_t start, end, len; 240 241 if (!(mode & FMODE_WRITE)) 242 return -EBADF; 243 244 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 245 return -EFAULT; 246 247 start = range[0]; 248 len = range[1]; 249 end = start + len - 1; 250 251 if (start & 511) 252 return -EINVAL; 253 if (len & 511) 254 return -EINVAL; 255 if (end >= (uint64_t)i_size_read(bdev->bd_inode)) 256 return -EINVAL; 257 if (end < start) 258 return -EINVAL; 259 260 /* Invalidate the page cache, including dirty pages */ 261 mapping = bdev->bd_inode->i_mapping; 262 truncate_inode_pages_range(mapping, start, end); 263 264 return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL, 265 BLKDEV_ZERO_NOUNMAP); 266 } 267 268 static int put_ushort(unsigned long arg, unsigned short val) 269 { 270 return put_user(val, (unsigned short __user *)arg); 271 } 272 273 static int put_int(unsigned long arg, int val) 274 { 275 return put_user(val, (int __user *)arg); 276 } 277 278 static int put_uint(unsigned long arg, unsigned int val) 279 { 280 return put_user(val, (unsigned int __user *)arg); 281 } 282 283 static int put_long(unsigned long arg, long val) 284 { 285 return put_user(val, (long __user *)arg); 286 } 287 288 static int put_ulong(unsigned long arg, unsigned long val) 289 { 290 return put_user(val, (unsigned long __user *)arg); 291 } 292 293 static int put_u64(unsigned long arg, u64 val) 294 { 295 return put_user(val, (u64 __user *)arg); 296 } 297 298 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, 299 unsigned cmd, unsigned long arg) 300 { 301 struct gendisk *disk = bdev->bd_disk; 302 303 if (disk->fops->ioctl) 304 return disk->fops->ioctl(bdev, mode, cmd, arg); 305 306 return -ENOTTY; 307 } 308 /* 309 * For the record: _GPL here is only because somebody decided to slap it 310 * on the previous export. Sheer idiocy, since it wasn't copyrightable 311 * at all and could be open-coded without any exports by anybody who cares. 312 */ 313 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); 314 315 static int blkdev_pr_register(struct block_device *bdev, 316 struct pr_registration __user *arg) 317 { 318 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 319 struct pr_registration reg; 320 321 if (!capable(CAP_SYS_ADMIN)) 322 return -EPERM; 323 if (!ops || !ops->pr_register) 324 return -EOPNOTSUPP; 325 if (copy_from_user(®, arg, sizeof(reg))) 326 return -EFAULT; 327 328 if (reg.flags & ~PR_FL_IGNORE_KEY) 329 return -EOPNOTSUPP; 330 return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags); 331 } 332 333 static int blkdev_pr_reserve(struct block_device *bdev, 334 struct pr_reservation __user *arg) 335 { 336 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 337 struct pr_reservation rsv; 338 339 if (!capable(CAP_SYS_ADMIN)) 340 return -EPERM; 341 if (!ops || !ops->pr_reserve) 342 return -EOPNOTSUPP; 343 if (copy_from_user(&rsv, arg, sizeof(rsv))) 344 return -EFAULT; 345 346 if (rsv.flags & ~PR_FL_IGNORE_KEY) 347 return -EOPNOTSUPP; 348 return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags); 349 } 350 351 static int blkdev_pr_release(struct block_device *bdev, 352 struct pr_reservation __user *arg) 353 { 354 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 355 struct pr_reservation rsv; 356 357 if (!capable(CAP_SYS_ADMIN)) 358 return -EPERM; 359 if (!ops || !ops->pr_release) 360 return -EOPNOTSUPP; 361 if (copy_from_user(&rsv, arg, sizeof(rsv))) 362 return -EFAULT; 363 364 if (rsv.flags) 365 return -EOPNOTSUPP; 366 return ops->pr_release(bdev, rsv.key, rsv.type); 367 } 368 369 static int blkdev_pr_preempt(struct block_device *bdev, 370 struct pr_preempt __user *arg, bool abort) 371 { 372 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 373 struct pr_preempt p; 374 375 if (!capable(CAP_SYS_ADMIN)) 376 return -EPERM; 377 if (!ops || !ops->pr_preempt) 378 return -EOPNOTSUPP; 379 if (copy_from_user(&p, arg, sizeof(p))) 380 return -EFAULT; 381 382 if (p.flags) 383 return -EOPNOTSUPP; 384 return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort); 385 } 386 387 static int blkdev_pr_clear(struct block_device *bdev, 388 struct pr_clear __user *arg) 389 { 390 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 391 struct pr_clear c; 392 393 if (!capable(CAP_SYS_ADMIN)) 394 return -EPERM; 395 if (!ops || !ops->pr_clear) 396 return -EOPNOTSUPP; 397 if (copy_from_user(&c, arg, sizeof(c))) 398 return -EFAULT; 399 400 if (c.flags) 401 return -EOPNOTSUPP; 402 return ops->pr_clear(bdev, c.key); 403 } 404 405 /* 406 * Is it an unrecognized ioctl? The correct returns are either 407 * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a 408 * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl 409 * code before returning. 410 * 411 * Confused drivers sometimes return EINVAL, which is wrong. It 412 * means "I understood the ioctl command, but the parameters to 413 * it were wrong". 414 * 415 * We should aim to just fix the broken drivers, the EINVAL case 416 * should go away. 417 */ 418 static inline int is_unrecognized_ioctl(int ret) 419 { 420 return ret == -EINVAL || 421 ret == -ENOTTY || 422 ret == -ENOIOCTLCMD; 423 } 424 425 static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode, 426 unsigned cmd, unsigned long arg) 427 { 428 int ret; 429 430 if (!capable(CAP_SYS_ADMIN)) 431 return -EACCES; 432 433 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 434 if (!is_unrecognized_ioctl(ret)) 435 return ret; 436 437 fsync_bdev(bdev); 438 invalidate_bdev(bdev); 439 return 0; 440 } 441 442 static int blkdev_roset(struct block_device *bdev, fmode_t mode, 443 unsigned cmd, unsigned long arg) 444 { 445 int ret, n; 446 447 if (!capable(CAP_SYS_ADMIN)) 448 return -EACCES; 449 450 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 451 if (!is_unrecognized_ioctl(ret)) 452 return ret; 453 if (get_user(n, (int __user *)arg)) 454 return -EFAULT; 455 set_device_ro(bdev, n); 456 return 0; 457 } 458 459 static int blkdev_getgeo(struct block_device *bdev, 460 struct hd_geometry __user *argp) 461 { 462 struct gendisk *disk = bdev->bd_disk; 463 struct hd_geometry geo; 464 int ret; 465 466 if (!argp) 467 return -EINVAL; 468 if (!disk->fops->getgeo) 469 return -ENOTTY; 470 471 /* 472 * We need to set the startsect first, the driver may 473 * want to override it. 474 */ 475 memset(&geo, 0, sizeof(geo)); 476 geo.start = get_start_sect(bdev); 477 ret = disk->fops->getgeo(bdev, &geo); 478 if (ret) 479 return ret; 480 if (copy_to_user(argp, &geo, sizeof(geo))) 481 return -EFAULT; 482 return 0; 483 } 484 485 /* set the logical block size */ 486 static int blkdev_bszset(struct block_device *bdev, fmode_t mode, 487 int __user *argp) 488 { 489 int ret, n; 490 491 if (!capable(CAP_SYS_ADMIN)) 492 return -EACCES; 493 if (!argp) 494 return -EINVAL; 495 if (get_user(n, argp)) 496 return -EFAULT; 497 498 if (!(mode & FMODE_EXCL)) { 499 bdgrab(bdev); 500 if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0) 501 return -EBUSY; 502 } 503 504 ret = set_blocksize(bdev, n); 505 if (!(mode & FMODE_EXCL)) 506 blkdev_put(bdev, mode | FMODE_EXCL); 507 return ret; 508 } 509 510 /* 511 * always keep this in sync with compat_blkdev_ioctl() 512 */ 513 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, 514 unsigned long arg) 515 { 516 void __user *argp = (void __user *)arg; 517 loff_t size; 518 unsigned int max_sectors; 519 520 switch (cmd) { 521 case BLKFLSBUF: 522 return blkdev_flushbuf(bdev, mode, cmd, arg); 523 case BLKROSET: 524 return blkdev_roset(bdev, mode, cmd, arg); 525 case BLKDISCARD: 526 return blk_ioctl_discard(bdev, mode, arg, 0); 527 case BLKSECDISCARD: 528 return blk_ioctl_discard(bdev, mode, arg, 529 BLKDEV_DISCARD_SECURE); 530 case BLKZEROOUT: 531 return blk_ioctl_zeroout(bdev, mode, arg); 532 case BLKREPORTZONE: 533 return blkdev_report_zones_ioctl(bdev, mode, cmd, arg); 534 case BLKRESETZONE: 535 return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg); 536 case BLKGETZONESZ: 537 return put_uint(arg, bdev_zone_sectors(bdev)); 538 case BLKGETNRZONES: 539 return put_uint(arg, blkdev_nr_zones(bdev)); 540 case HDIO_GETGEO: 541 return blkdev_getgeo(bdev, argp); 542 case BLKRAGET: 543 case BLKFRAGET: 544 if (!arg) 545 return -EINVAL; 546 return put_long(arg, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512); 547 case BLKROGET: 548 return put_int(arg, bdev_read_only(bdev) != 0); 549 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */ 550 return put_int(arg, block_size(bdev)); 551 case BLKSSZGET: /* get block device logical block size */ 552 return put_int(arg, bdev_logical_block_size(bdev)); 553 case BLKPBSZGET: /* get block device physical block size */ 554 return put_uint(arg, bdev_physical_block_size(bdev)); 555 case BLKIOMIN: 556 return put_uint(arg, bdev_io_min(bdev)); 557 case BLKIOOPT: 558 return put_uint(arg, bdev_io_opt(bdev)); 559 case BLKALIGNOFF: 560 return put_int(arg, bdev_alignment_offset(bdev)); 561 case BLKDISCARDZEROES: 562 return put_uint(arg, 0); 563 case BLKSECTGET: 564 max_sectors = min_t(unsigned int, USHRT_MAX, 565 queue_max_sectors(bdev_get_queue(bdev))); 566 return put_ushort(arg, max_sectors); 567 case BLKROTATIONAL: 568 return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev))); 569 case BLKRASET: 570 case BLKFRASET: 571 if(!capable(CAP_SYS_ADMIN)) 572 return -EACCES; 573 bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE; 574 return 0; 575 case BLKBSZSET: 576 return blkdev_bszset(bdev, mode, argp); 577 case BLKPG: 578 return blkpg_ioctl(bdev, argp); 579 case BLKRRPART: 580 return blkdev_reread_part(bdev); 581 case BLKGETSIZE: 582 size = i_size_read(bdev->bd_inode); 583 if ((size >> 9) > ~0UL) 584 return -EFBIG; 585 return put_ulong(arg, size >> 9); 586 case BLKGETSIZE64: 587 return put_u64(arg, i_size_read(bdev->bd_inode)); 588 case BLKTRACESTART: 589 case BLKTRACESTOP: 590 case BLKTRACESETUP: 591 case BLKTRACETEARDOWN: 592 return blk_trace_ioctl(bdev, cmd, argp); 593 case IOC_PR_REGISTER: 594 return blkdev_pr_register(bdev, argp); 595 case IOC_PR_RESERVE: 596 return blkdev_pr_reserve(bdev, argp); 597 case IOC_PR_RELEASE: 598 return blkdev_pr_release(bdev, argp); 599 case IOC_PR_PREEMPT: 600 return blkdev_pr_preempt(bdev, argp, false); 601 case IOC_PR_PREEMPT_ABORT: 602 return blkdev_pr_preempt(bdev, argp, true); 603 case IOC_PR_CLEAR: 604 return blkdev_pr_clear(bdev, argp); 605 default: 606 return __blkdev_driver_ioctl(bdev, mode, cmd, arg); 607 } 608 } 609 EXPORT_SYMBOL_GPL(blkdev_ioctl); 610