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85#include <linux/kernel.h>
86#include <linux/crc32.h>
87#include <linux/ctype.h>
88#include <linux/math64.h>
89#include <linux/slab.h>
90#include "check.h"
91#include "efi.h"
92
93
94
95
96
97static int force_gpt;
98static int __init
99force_gpt_fn(char *str)
100{
101 force_gpt = 1;
102 return 1;
103}
104__setup("gpt", force_gpt_fn);
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119static inline u32
120efi_crc32(const void *buf, unsigned long len)
121{
122 return (crc32(~0L, buf, len) ^ ~0L);
123}
124
125
126
127
128
129
130
131
132
133
134static u64 last_lba(struct gendisk *disk)
135{
136 return div_u64(disk->part0->bd_inode->i_size,
137 queue_logical_block_size(disk->queue)) - 1ULL;
138}
139
140static inline int pmbr_part_valid(gpt_mbr_record *part)
141{
142 if (part->os_type != EFI_PMBR_OSTYPE_EFI_GPT)
143 goto invalid;
144
145
146 if (le32_to_cpu(part->starting_lba) != GPT_PRIMARY_PARTITION_TABLE_LBA)
147 goto invalid;
148
149 return GPT_MBR_PROTECTIVE;
150invalid:
151 return 0;
152}
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172static int is_pmbr_valid(legacy_mbr *mbr, sector_t total_sectors)
173{
174 uint32_t sz = 0;
175 int i, part = 0, ret = 0;
176
177 if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
178 goto done;
179
180 for (i = 0; i < 4; i++) {
181 ret = pmbr_part_valid(&mbr->partition_record[i]);
182 if (ret == GPT_MBR_PROTECTIVE) {
183 part = i;
184
185
186
187
188
189 goto check_hybrid;
190 }
191 }
192
193 if (ret != GPT_MBR_PROTECTIVE)
194 goto done;
195check_hybrid:
196 for (i = 0; i < 4; i++)
197 if ((mbr->partition_record[i].os_type !=
198 EFI_PMBR_OSTYPE_EFI_GPT) &&
199 (mbr->partition_record[i].os_type != 0x00))
200 ret = GPT_MBR_HYBRID;
201
202
203
204
205
206
207
208
209
210
211
212
213
214 if (ret == GPT_MBR_PROTECTIVE) {
215 sz = le32_to_cpu(mbr->partition_record[part].size_in_lba);
216 if (sz != (uint32_t) total_sectors - 1 && sz != 0xFFFFFFFF)
217 pr_debug("GPT: mbr size in lba (%u) different than whole disk (%u).\n",
218 sz, min_t(uint32_t,
219 total_sectors - 1, 0xFFFFFFFF));
220 }
221done:
222 return ret;
223}
224
225
226
227
228
229
230
231
232
233
234
235static size_t read_lba(struct parsed_partitions *state,
236 u64 lba, u8 *buffer, size_t count)
237{
238 size_t totalreadcount = 0;
239 sector_t n = lba *
240 (queue_logical_block_size(state->disk->queue) / 512);
241
242 if (!buffer || lba > last_lba(state->disk))
243 return 0;
244
245 while (count) {
246 int copied = 512;
247 Sector sect;
248 unsigned char *data = read_part_sector(state, n++, §);
249 if (!data)
250 break;
251 if (copied > count)
252 copied = count;
253 memcpy(buffer, data, copied);
254 put_dev_sector(sect);
255 buffer += copied;
256 totalreadcount +=copied;
257 count -= copied;
258 }
259 return totalreadcount;
260}
261
262
263
264
265
266
267
268
269
270
271static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state,
272 gpt_header *gpt)
273{
274 size_t count;
275 gpt_entry *pte;
276
277 if (!gpt)
278 return NULL;
279
280 count = (size_t)le32_to_cpu(gpt->num_partition_entries) *
281 le32_to_cpu(gpt->sizeof_partition_entry);
282 if (!count)
283 return NULL;
284 pte = kmalloc(count, GFP_KERNEL);
285 if (!pte)
286 return NULL;
287
288 if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba),
289 (u8 *) pte, count) < count) {
290 kfree(pte);
291 pte=NULL;
292 return NULL;
293 }
294 return pte;
295}
296
297
298
299
300
301
302
303
304
305
306static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state,
307 u64 lba)
308{
309 gpt_header *gpt;
310 unsigned ssz = queue_logical_block_size(state->disk->queue);
311
312 gpt = kmalloc(ssz, GFP_KERNEL);
313 if (!gpt)
314 return NULL;
315
316 if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) {
317 kfree(gpt);
318 gpt=NULL;
319 return NULL;
320 }
321
322 return gpt;
323}
324
325
326
327
328
329
330
331
332
333
334
335static int is_gpt_valid(struct parsed_partitions *state, u64 lba,
336 gpt_header **gpt, gpt_entry **ptes)
337{
338 u32 crc, origcrc;
339 u64 lastlba, pt_size;
340
341 if (!ptes)
342 return 0;
343 if (!(*gpt = alloc_read_gpt_header(state, lba)))
344 return 0;
345
346
347 if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) {
348 pr_debug("GUID Partition Table Header signature is wrong:"
349 "%lld != %lld\n",
350 (unsigned long long)le64_to_cpu((*gpt)->signature),
351 (unsigned long long)GPT_HEADER_SIGNATURE);
352 goto fail;
353 }
354
355
356 if (le32_to_cpu((*gpt)->header_size) >
357 queue_logical_block_size(state->disk->queue)) {
358 pr_debug("GUID Partition Table Header size is too large: %u > %u\n",
359 le32_to_cpu((*gpt)->header_size),
360 queue_logical_block_size(state->disk->queue));
361 goto fail;
362 }
363
364
365 if (le32_to_cpu((*gpt)->header_size) < sizeof(gpt_header)) {
366 pr_debug("GUID Partition Table Header size is too small: %u < %zu\n",
367 le32_to_cpu((*gpt)->header_size),
368 sizeof(gpt_header));
369 goto fail;
370 }
371
372
373 origcrc = le32_to_cpu((*gpt)->header_crc32);
374 (*gpt)->header_crc32 = 0;
375 crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size));
376
377 if (crc != origcrc) {
378 pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n",
379 crc, origcrc);
380 goto fail;
381 }
382 (*gpt)->header_crc32 = cpu_to_le32(origcrc);
383
384
385
386 if (le64_to_cpu((*gpt)->my_lba) != lba) {
387 pr_debug("GPT my_lba incorrect: %lld != %lld\n",
388 (unsigned long long)le64_to_cpu((*gpt)->my_lba),
389 (unsigned long long)lba);
390 goto fail;
391 }
392
393
394
395
396 lastlba = last_lba(state->disk);
397 if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) {
398 pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n",
399 (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba),
400 (unsigned long long)lastlba);
401 goto fail;
402 }
403 if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) {
404 pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n",
405 (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba),
406 (unsigned long long)lastlba);
407 goto fail;
408 }
409 if (le64_to_cpu((*gpt)->last_usable_lba) < le64_to_cpu((*gpt)->first_usable_lba)) {
410 pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n",
411 (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba),
412 (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba));
413 goto fail;
414 }
415
416 if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) {
417 pr_debug("GUID Partition Entry Size check failed.\n");
418 goto fail;
419 }
420
421
422 pt_size = (u64)le32_to_cpu((*gpt)->num_partition_entries) *
423 le32_to_cpu((*gpt)->sizeof_partition_entry);
424 if (pt_size > KMALLOC_MAX_SIZE) {
425 pr_debug("GUID Partition Table is too large: %llu > %lu bytes\n",
426 (unsigned long long)pt_size, KMALLOC_MAX_SIZE);
427 goto fail;
428 }
429
430 if (!(*ptes = alloc_read_gpt_entries(state, *gpt)))
431 goto fail;
432
433
434 crc = efi_crc32((const unsigned char *) (*ptes), pt_size);
435
436 if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) {
437 pr_debug("GUID Partition Entry Array CRC check failed.\n");
438 goto fail_ptes;
439 }
440
441
442 return 1;
443
444 fail_ptes:
445 kfree(*ptes);
446 *ptes = NULL;
447 fail:
448 kfree(*gpt);
449 *gpt = NULL;
450 return 0;
451}
452
453
454
455
456
457
458
459
460static inline int
461is_pte_valid(const gpt_entry *pte, const u64 lastlba)
462{
463 if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) ||
464 le64_to_cpu(pte->starting_lba) > lastlba ||
465 le64_to_cpu(pte->ending_lba) > lastlba)
466 return 0;
467 return 1;
468}
469
470
471
472
473
474
475
476
477
478
479
480static void
481compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba)
482{
483 int error_found = 0;
484 if (!pgpt || !agpt)
485 return;
486 if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) {
487 pr_warn("GPT:Primary header LBA != Alt. header alternate_lba\n");
488 pr_warn("GPT:%lld != %lld\n",
489 (unsigned long long)le64_to_cpu(pgpt->my_lba),
490 (unsigned long long)le64_to_cpu(agpt->alternate_lba));
491 error_found++;
492 }
493 if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) {
494 pr_warn("GPT:Primary header alternate_lba != Alt. header my_lba\n");
495 pr_warn("GPT:%lld != %lld\n",
496 (unsigned long long)le64_to_cpu(pgpt->alternate_lba),
497 (unsigned long long)le64_to_cpu(agpt->my_lba));
498 error_found++;
499 }
500 if (le64_to_cpu(pgpt->first_usable_lba) !=
501 le64_to_cpu(agpt->first_usable_lba)) {
502 pr_warn("GPT:first_usable_lbas don't match.\n");
503 pr_warn("GPT:%lld != %lld\n",
504 (unsigned long long)le64_to_cpu(pgpt->first_usable_lba),
505 (unsigned long long)le64_to_cpu(agpt->first_usable_lba));
506 error_found++;
507 }
508 if (le64_to_cpu(pgpt->last_usable_lba) !=
509 le64_to_cpu(agpt->last_usable_lba)) {
510 pr_warn("GPT:last_usable_lbas don't match.\n");
511 pr_warn("GPT:%lld != %lld\n",
512 (unsigned long long)le64_to_cpu(pgpt->last_usable_lba),
513 (unsigned long long)le64_to_cpu(agpt->last_usable_lba));
514 error_found++;
515 }
516 if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) {
517 pr_warn("GPT:disk_guids don't match.\n");
518 error_found++;
519 }
520 if (le32_to_cpu(pgpt->num_partition_entries) !=
521 le32_to_cpu(agpt->num_partition_entries)) {
522 pr_warn("GPT:num_partition_entries don't match: "
523 "0x%x != 0x%x\n",
524 le32_to_cpu(pgpt->num_partition_entries),
525 le32_to_cpu(agpt->num_partition_entries));
526 error_found++;
527 }
528 if (le32_to_cpu(pgpt->sizeof_partition_entry) !=
529 le32_to_cpu(agpt->sizeof_partition_entry)) {
530 pr_warn("GPT:sizeof_partition_entry values don't match: "
531 "0x%x != 0x%x\n",
532 le32_to_cpu(pgpt->sizeof_partition_entry),
533 le32_to_cpu(agpt->sizeof_partition_entry));
534 error_found++;
535 }
536 if (le32_to_cpu(pgpt->partition_entry_array_crc32) !=
537 le32_to_cpu(agpt->partition_entry_array_crc32)) {
538 pr_warn("GPT:partition_entry_array_crc32 values don't match: "
539 "0x%x != 0x%x\n",
540 le32_to_cpu(pgpt->partition_entry_array_crc32),
541 le32_to_cpu(agpt->partition_entry_array_crc32));
542 error_found++;
543 }
544 if (le64_to_cpu(pgpt->alternate_lba) != lastlba) {
545 pr_warn("GPT:Primary header thinks Alt. header is not at the end of the disk.\n");
546 pr_warn("GPT:%lld != %lld\n",
547 (unsigned long long)le64_to_cpu(pgpt->alternate_lba),
548 (unsigned long long)lastlba);
549 error_found++;
550 }
551
552 if (le64_to_cpu(agpt->my_lba) != lastlba) {
553 pr_warn("GPT:Alternate GPT header not at the end of the disk.\n");
554 pr_warn("GPT:%lld != %lld\n",
555 (unsigned long long)le64_to_cpu(agpt->my_lba),
556 (unsigned long long)lastlba);
557 error_found++;
558 }
559
560 if (error_found)
561 pr_warn("GPT: Use GNU Parted to correct GPT errors.\n");
562 return;
563}
564
565
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579
580
581static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt,
582 gpt_entry **ptes)
583{
584 int good_pgpt = 0, good_agpt = 0, good_pmbr = 0;
585 gpt_header *pgpt = NULL, *agpt = NULL;
586 gpt_entry *pptes = NULL, *aptes = NULL;
587 legacy_mbr *legacymbr;
588 struct gendisk *disk = state->disk;
589 const struct block_device_operations *fops = disk->fops;
590 sector_t total_sectors = get_capacity(state->disk);
591 u64 lastlba;
592
593 if (!ptes)
594 return 0;
595
596 lastlba = last_lba(state->disk);
597 if (!force_gpt) {
598
599 legacymbr = kzalloc(sizeof(*legacymbr), GFP_KERNEL);
600 if (!legacymbr)
601 goto fail;
602
603 read_lba(state, 0, (u8 *)legacymbr, sizeof(*legacymbr));
604 good_pmbr = is_pmbr_valid(legacymbr, total_sectors);
605 kfree(legacymbr);
606
607 if (!good_pmbr)
608 goto fail;
609
610 pr_debug("Device has a %s MBR\n",
611 good_pmbr == GPT_MBR_PROTECTIVE ?
612 "protective" : "hybrid");
613 }
614
615 good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA,
616 &pgpt, &pptes);
617 if (good_pgpt)
618 good_agpt = is_gpt_valid(state,
619 le64_to_cpu(pgpt->alternate_lba),
620 &agpt, &aptes);
621 if (!good_agpt && force_gpt)
622 good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes);
623
624 if (!good_agpt && force_gpt && fops->alternative_gpt_sector) {
625 sector_t agpt_sector;
626 int err;
627
628 err = fops->alternative_gpt_sector(disk, &agpt_sector);
629 if (!err)
630 good_agpt = is_gpt_valid(state, agpt_sector,
631 &agpt, &aptes);
632 }
633
634
635 if (!good_pgpt && !good_agpt)
636 goto fail;
637
638 compare_gpts(pgpt, agpt, lastlba);
639
640
641 if (good_pgpt) {
642 *gpt = pgpt;
643 *ptes = pptes;
644 kfree(agpt);
645 kfree(aptes);
646 if (!good_agpt)
647 pr_warn("Alternate GPT is invalid, using primary GPT.\n");
648 return 1;
649 }
650 else if (good_agpt) {
651 *gpt = agpt;
652 *ptes = aptes;
653 kfree(pgpt);
654 kfree(pptes);
655 pr_warn("Primary GPT is invalid, using alternate GPT.\n");
656 return 1;
657 }
658
659 fail:
660 kfree(pgpt);
661 kfree(agpt);
662 kfree(pptes);
663 kfree(aptes);
664 *gpt = NULL;
665 *ptes = NULL;
666 return 0;
667}
668
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675
676
677
678static void utf16_le_to_7bit(const __le16 *in, unsigned int size, u8 *out)
679{
680 unsigned int i = 0;
681
682 out[size] = 0;
683
684 while (i < size) {
685 u8 c = le16_to_cpu(in[i]) & 0xff;
686
687 if (c && !isprint(c))
688 c = '!';
689 out[i] = c;
690 i++;
691 }
692}
693
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711
712
713int efi_partition(struct parsed_partitions *state)
714{
715 gpt_header *gpt = NULL;
716 gpt_entry *ptes = NULL;
717 u32 i;
718 unsigned ssz = queue_logical_block_size(state->disk->queue) / 512;
719
720 if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) {
721 kfree(gpt);
722 kfree(ptes);
723 return 0;
724 }
725
726 pr_debug("GUID Partition Table is valid! Yea!\n");
727
728 for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) {
729 struct partition_meta_info *info;
730 unsigned label_max;
731 u64 start = le64_to_cpu(ptes[i].starting_lba);
732 u64 size = le64_to_cpu(ptes[i].ending_lba) -
733 le64_to_cpu(ptes[i].starting_lba) + 1ULL;
734
735 if (!is_pte_valid(&ptes[i], last_lba(state->disk)))
736 continue;
737
738 put_partition(state, i+1, start * ssz, size * ssz);
739
740
741 if (!efi_guidcmp(ptes[i].partition_type_guid, PARTITION_LINUX_RAID_GUID))
742 state->parts[i + 1].flags = ADDPART_FLAG_RAID;
743
744 info = &state->parts[i + 1].info;
745 efi_guid_to_str(&ptes[i].unique_partition_guid, info->uuid);
746
747
748 label_max = min(ARRAY_SIZE(info->volname) - 1,
749 ARRAY_SIZE(ptes[i].partition_name));
750 utf16_le_to_7bit(ptes[i].partition_name, label_max, info->volname);
751 state->parts[i + 1].has_info = true;
752 }
753 kfree(ptes);
754 kfree(gpt);
755 strlcat(state->pp_buf, "\n", PAGE_SIZE);
756 return 1;
757}
758