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a497ee34 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /************************************************************ |
3 | * EFI GUID Partition Table handling | |
7d13af32 KZ |
4 | * |
5 | * http://www.uefi.org/specs/ | |
6 | * http://www.intel.com/technology/efi/ | |
7 | * | |
1da177e4 LT |
8 | * efi.[ch] by Matt Domsch <Matt_Domsch@dell.com> |
9 | * Copyright 2000,2001,2002,2004 Dell Inc. | |
10 | * | |
1da177e4 LT |
11 | * TODO: |
12 | * | |
13 | * Changelog: | |
70f637e9 DB |
14 | * Mon August 5th, 2013 Davidlohr Bueso <davidlohr@hp.com> |
15 | * - detect hybrid MBRs, tighter pMBR checking & cleanups. | |
16 | * | |
1da177e4 LT |
17 | * Mon Nov 09 2004 Matt Domsch <Matt_Domsch@dell.com> |
18 | * - test for valid PMBR and valid PGPT before ever reading | |
19 | * AGPT, allow override with 'gpt' kernel command line option. | |
20 | * - check for first/last_usable_lba outside of size of disk | |
21 | * | |
22 | * Tue Mar 26 2002 Matt Domsch <Matt_Domsch@dell.com> | |
23 | * - Ported to 2.5.7-pre1 and 2.5.7-dj2 | |
24 | * - Applied patch to avoid fault in alternate header handling | |
25 | * - cleaned up find_valid_gpt | |
26 | * - On-disk structure and copy in memory is *always* LE now - | |
27 | * swab fields as needed | |
28 | * - remove print_gpt_header() | |
29 | * - only use first max_p partition entries, to keep the kernel minor number | |
30 | * and partition numbers tied. | |
31 | * | |
32 | * Mon Feb 04 2002 Matt Domsch <Matt_Domsch@dell.com> | |
33 | * - Removed __PRIPTR_PREFIX - not being used | |
34 | * | |
35 | * Mon Jan 14 2002 Matt Domsch <Matt_Domsch@dell.com> | |
36 | * - Ported to 2.5.2-pre11 + library crc32 patch Linus applied | |
37 | * | |
38 | * Thu Dec 6 2001 Matt Domsch <Matt_Domsch@dell.com> | |
39 | * - Added compare_gpts(). | |
40 | * - moved le_efi_guid_to_cpus() back into this file. GPT is the only | |
41 | * thing that keeps EFI GUIDs on disk. | |
42 | * - Changed gpt structure names and members to be simpler and more Linux-like. | |
43 | * | |
44 | * Wed Oct 17 2001 Matt Domsch <Matt_Domsch@dell.com> | |
45 | * - Removed CONFIG_DEVFS_VOLUMES_UUID code entirely per Martin Wilck | |
46 | * | |
47 | * Wed Oct 10 2001 Matt Domsch <Matt_Domsch@dell.com> | |
48 | * - Changed function comments to DocBook style per Andreas Dilger suggestion. | |
49 | * | |
50 | * Mon Oct 08 2001 Matt Domsch <Matt_Domsch@dell.com> | |
51 | * - Change read_lba() to use the page cache per Al Viro's work. | |
52 | * - print u64s properly on all architectures | |
53 | * - fixed debug_printk(), now Dprintk() | |
54 | * | |
55 | * Mon Oct 01 2001 Matt Domsch <Matt_Domsch@dell.com> | |
56 | * - Style cleanups | |
57 | * - made most functions static | |
58 | * - Endianness addition | |
59 | * - remove test for second alternate header, as it's not per spec, | |
60 | * and is unnecessary. There's now a method to read/write the last | |
61 | * sector of an odd-sized disk from user space. No tools have ever | |
62 | * been released which used this code, so it's effectively dead. | |
63 | * - Per Asit Mallick of Intel, added a test for a valid PMBR. | |
64 | * - Added kernel command line option 'gpt' to override valid PMBR test. | |
65 | * | |
66 | * Wed Jun 6 2001 Martin Wilck <Martin.Wilck@Fujitsu-Siemens.com> | |
67 | * - added devfs volume UUID support (/dev/volumes/uuids) for | |
68 | * mounting file systems by the partition GUID. | |
69 | * | |
70 | * Tue Dec 5 2000 Matt Domsch <Matt_Domsch@dell.com> | |
71 | * - Moved crc32() to linux/lib, added efi_crc32(). | |
72 | * | |
73 | * Thu Nov 30 2000 Matt Domsch <Matt_Domsch@dell.com> | |
74 | * - Replaced Intel's CRC32 function with an equivalent | |
75 | * non-license-restricted version. | |
76 | * | |
77 | * Wed Oct 25 2000 Matt Domsch <Matt_Domsch@dell.com> | |
78 | * - Fixed the last_lba() call to return the proper last block | |
79 | * | |
80 | * Thu Oct 12 2000 Matt Domsch <Matt_Domsch@dell.com> | |
81 | * - Thanks to Andries Brouwer for his debugging assistance. | |
82 | * - Code works, detects all the partitions. | |
83 | * | |
84 | ************************************************************/ | |
49204c11 | 85 | #include <linux/kernel.h> |
1da177e4 | 86 | #include <linux/crc32.h> |
eec7ecfe | 87 | #include <linux/ctype.h> |
7d13af32 | 88 | #include <linux/math64.h> |
5a0e3ad6 | 89 | #include <linux/slab.h> |
1da177e4 LT |
90 | #include "check.h" |
91 | #include "efi.h" | |
92 | ||
1da177e4 LT |
93 | /* This allows a kernel command line option 'gpt' to override |
94 | * the test for invalid PMBR. Not __initdata because reloading | |
95 | * the partition tables happens after init too. | |
96 | */ | |
97 | static int force_gpt; | |
98 | static int __init | |
99 | force_gpt_fn(char *str) | |
100 | { | |
101 | force_gpt = 1; | |
102 | return 1; | |
103 | } | |
104 | __setup("gpt", force_gpt_fn); | |
105 | ||
106 | ||
107 | /** | |
108 | * efi_crc32() - EFI version of crc32 function | |
109 | * @buf: buffer to calculate crc32 of | |
16e15565 | 110 | * @len: length of buf |
1da177e4 LT |
111 | * |
112 | * Description: Returns EFI-style CRC32 value for @buf | |
113 | * | |
114 | * This function uses the little endian Ethernet polynomial | |
115 | * but seeds the function with ~0, and xor's with ~0 at the end. | |
116 | * Note, the EFI Specification, v1.02, has a reference to | |
117 | * Dr. Dobbs Journal, May 1994 (actually it's in May 1992). | |
118 | */ | |
119 | static inline u32 | |
120 | efi_crc32(const void *buf, unsigned long len) | |
121 | { | |
122 | return (crc32(~0L, buf, len) ^ ~0L); | |
123 | } | |
124 | ||
125 | /** | |
126 | * last_lba(): return number of last logical block of device | |
127 | * @bdev: block device | |
128 | * | |
129 | * Description: Returns last LBA value on success, 0 on error. | |
130 | * This is stored (by sd and ide-geometry) in | |
131 | * the part[0] entry for this disk, and is the number of | |
132 | * physical sectors available on the disk. | |
133 | */ | |
1493bf21 | 134 | static u64 last_lba(struct block_device *bdev) |
1da177e4 LT |
135 | { |
136 | if (!bdev || !bdev->bd_inode) | |
137 | return 0; | |
7d13af32 KZ |
138 | return div_u64(bdev->bd_inode->i_size, |
139 | bdev_logical_block_size(bdev)) - 1ULL; | |
1da177e4 LT |
140 | } |
141 | ||
c2ebdc24 | 142 | static inline int pmbr_part_valid(gpt_mbr_record *part) |
1da177e4 | 143 | { |
33afd7a7 DB |
144 | if (part->os_type != EFI_PMBR_OSTYPE_EFI_GPT) |
145 | goto invalid; | |
146 | ||
147 | /* set to 0x00000001 (i.e., the LBA of the GPT Partition Header) */ | |
148 | if (le32_to_cpu(part->starting_lba) != GPT_PRIMARY_PARTITION_TABLE_LBA) | |
149 | goto invalid; | |
150 | ||
b05ebbbb | 151 | return GPT_MBR_PROTECTIVE; |
33afd7a7 DB |
152 | invalid: |
153 | return 0; | |
1da177e4 LT |
154 | } |
155 | ||
156 | /** | |
157 | * is_pmbr_valid(): test Protective MBR for validity | |
158 | * @mbr: pointer to a legacy mbr structure | |
27a7c642 | 159 | * @total_sectors: amount of sectors in the device |
1da177e4 | 160 | * |
b05ebbbb DB |
161 | * Description: Checks for a valid protective or hybrid |
162 | * master boot record (MBR). The validity of a pMBR depends | |
163 | * on all of the following properties: | |
1da177e4 LT |
164 | * 1) MSDOS signature is in the last two bytes of the MBR |
165 | * 2) One partition of type 0xEE is found | |
b05ebbbb DB |
166 | * |
167 | * In addition, a hybrid MBR will have up to three additional | |
168 | * primary partitions, which point to the same space that's | |
169 | * marked out by up to three GPT partitions. | |
170 | * | |
171 | * Returns 0 upon invalid MBR, or GPT_MBR_PROTECTIVE or | |
172 | * GPT_MBR_HYBRID depending on the device layout. | |
1da177e4 | 173 | */ |
27a7c642 | 174 | static int is_pmbr_valid(legacy_mbr *mbr, sector_t total_sectors) |
1da177e4 | 175 | { |
6b02fa59 | 176 | uint32_t sz = 0; |
27a7c642 | 177 | int i, part = 0, ret = 0; /* invalid by default */ |
b05ebbbb | 178 | |
1da177e4 | 179 | if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE) |
b05ebbbb DB |
180 | goto done; |
181 | ||
182 | for (i = 0; i < 4; i++) { | |
183 | ret = pmbr_part_valid(&mbr->partition_record[i]); | |
184 | if (ret == GPT_MBR_PROTECTIVE) { | |
27a7c642 | 185 | part = i; |
b05ebbbb DB |
186 | /* |
187 | * Ok, we at least know that there's a protective MBR, | |
188 | * now check if there are other partition types for | |
189 | * hybrid MBR. | |
190 | */ | |
191 | goto check_hybrid; | |
192 | } | |
193 | } | |
194 | ||
195 | if (ret != GPT_MBR_PROTECTIVE) | |
196 | goto done; | |
197 | check_hybrid: | |
1da177e4 | 198 | for (i = 0; i < 4; i++) |
b05ebbbb DB |
199 | if ((mbr->partition_record[i].os_type != |
200 | EFI_PMBR_OSTYPE_EFI_GPT) && | |
201 | (mbr->partition_record[i].os_type != 0x00)) | |
202 | ret = GPT_MBR_HYBRID; | |
27a7c642 DB |
203 | |
204 | /* | |
205 | * Protective MBRs take up the lesser of the whole disk | |
206 | * or 2 TiB (32bit LBA), ignoring the rest of the disk. | |
6b02fa59 DB |
207 | * Some partitioning programs, nonetheless, choose to set |
208 | * the size to the maximum 32-bit limitation, disregarding | |
209 | * the disk size. | |
27a7c642 DB |
210 | * |
211 | * Hybrid MBRs do not necessarily comply with this. | |
87fc0ad2 DA |
212 | * |
213 | * Consider a bad value here to be a warning to support dd'ing | |
214 | * an image from a smaller disk to a larger disk. | |
27a7c642 DB |
215 | */ |
216 | if (ret == GPT_MBR_PROTECTIVE) { | |
6b02fa59 DB |
217 | sz = le32_to_cpu(mbr->partition_record[part].size_in_lba); |
218 | if (sz != (uint32_t) total_sectors - 1 && sz != 0xFFFFFFFF) | |
87fc0ad2 DA |
219 | pr_debug("GPT: mbr size in lba (%u) different than whole disk (%u).\n", |
220 | sz, min_t(uint32_t, | |
221 | total_sectors - 1, 0xFFFFFFFF)); | |
27a7c642 | 222 | } |
b05ebbbb DB |
223 | done: |
224 | return ret; | |
1da177e4 LT |
225 | } |
226 | ||
227 | /** | |
228 | * read_lba(): Read bytes from disk, starting at given LBA | |
16e15565 FF |
229 | * @state: disk parsed partitions |
230 | * @lba: the Logical Block Address of the partition table | |
231 | * @buffer: destination buffer | |
232 | * @count: bytes to read | |
1da177e4 | 233 | * |
1493bf21 | 234 | * Description: Reads @count bytes from @state->bdev into @buffer. |
1da177e4 LT |
235 | * Returns number of bytes read on success, 0 on error. |
236 | */ | |
1493bf21 TH |
237 | static size_t read_lba(struct parsed_partitions *state, |
238 | u64 lba, u8 *buffer, size_t count) | |
1da177e4 LT |
239 | { |
240 | size_t totalreadcount = 0; | |
1493bf21 | 241 | struct block_device *bdev = state->bdev; |
7d13af32 | 242 | sector_t n = lba * (bdev_logical_block_size(bdev) / 512); |
1da177e4 | 243 | |
1493bf21 | 244 | if (!buffer || lba > last_lba(bdev)) |
1da177e4 LT |
245 | return 0; |
246 | ||
247 | while (count) { | |
248 | int copied = 512; | |
249 | Sector sect; | |
1493bf21 | 250 | unsigned char *data = read_part_sector(state, n++, §); |
1da177e4 LT |
251 | if (!data) |
252 | break; | |
253 | if (copied > count) | |
254 | copied = count; | |
255 | memcpy(buffer, data, copied); | |
256 | put_dev_sector(sect); | |
257 | buffer += copied; | |
258 | totalreadcount +=copied; | |
259 | count -= copied; | |
260 | } | |
261 | return totalreadcount; | |
262 | } | |
263 | ||
264 | /** | |
265 | * alloc_read_gpt_entries(): reads partition entries from disk | |
16e15565 FF |
266 | * @state: disk parsed partitions |
267 | * @gpt: GPT header | |
1da177e4 LT |
268 | * |
269 | * Description: Returns ptes on success, NULL on error. | |
270 | * Allocates space for PTEs based on information found in @gpt. | |
271 | * Notes: remember to free pte when you're done! | |
272 | */ | |
1493bf21 TH |
273 | static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state, |
274 | gpt_header *gpt) | |
1da177e4 LT |
275 | { |
276 | size_t count; | |
277 | gpt_entry *pte; | |
1493bf21 TH |
278 | |
279 | if (!gpt) | |
1da177e4 LT |
280 | return NULL; |
281 | ||
c5082b70 | 282 | count = (size_t)le32_to_cpu(gpt->num_partition_entries) * |
1da177e4 LT |
283 | le32_to_cpu(gpt->sizeof_partition_entry); |
284 | if (!count) | |
285 | return NULL; | |
ea56505b | 286 | pte = kmalloc(count, GFP_KERNEL); |
1da177e4 LT |
287 | if (!pte) |
288 | return NULL; | |
1da177e4 | 289 | |
1493bf21 | 290 | if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba), |
70f637e9 | 291 | (u8 *) pte, count) < count) { |
1da177e4 LT |
292 | kfree(pte); |
293 | pte=NULL; | |
294 | return NULL; | |
295 | } | |
296 | return pte; | |
297 | } | |
298 | ||
299 | /** | |
300 | * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk | |
16e15565 FF |
301 | * @state: disk parsed partitions |
302 | * @lba: the Logical Block Address of the partition table | |
1da177e4 LT |
303 | * |
304 | * Description: returns GPT header on success, NULL on error. Allocates | |
1493bf21 | 305 | * and fills a GPT header starting at @ from @state->bdev. |
1da177e4 LT |
306 | * Note: remember to free gpt when finished with it. |
307 | */ | |
1493bf21 TH |
308 | static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state, |
309 | u64 lba) | |
1da177e4 LT |
310 | { |
311 | gpt_header *gpt; | |
1493bf21 | 312 | unsigned ssz = bdev_logical_block_size(state->bdev); |
1da177e4 | 313 | |
ea56505b | 314 | gpt = kmalloc(ssz, GFP_KERNEL); |
1da177e4 LT |
315 | if (!gpt) |
316 | return NULL; | |
1da177e4 | 317 | |
1493bf21 | 318 | if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) { |
1da177e4 LT |
319 | kfree(gpt); |
320 | gpt=NULL; | |
321 | return NULL; | |
322 | } | |
323 | ||
324 | return gpt; | |
325 | } | |
326 | ||
327 | /** | |
328 | * is_gpt_valid() - tests one GPT header and PTEs for validity | |
16e15565 FF |
329 | * @state: disk parsed partitions |
330 | * @lba: logical block address of the GPT header to test | |
331 | * @gpt: GPT header ptr, filled on return. | |
332 | * @ptes: PTEs ptr, filled on return. | |
1da177e4 LT |
333 | * |
334 | * Description: returns 1 if valid, 0 on error. | |
335 | * If valid, returns pointers to newly allocated GPT header and PTEs. | |
336 | */ | |
1493bf21 TH |
337 | static int is_gpt_valid(struct parsed_partitions *state, u64 lba, |
338 | gpt_header **gpt, gpt_entry **ptes) | |
1da177e4 LT |
339 | { |
340 | u32 crc, origcrc; | |
c5082b70 | 341 | u64 lastlba, pt_size; |
1da177e4 | 342 | |
1493bf21 | 343 | if (!ptes) |
1da177e4 | 344 | return 0; |
1493bf21 | 345 | if (!(*gpt = alloc_read_gpt_header(state, lba))) |
1da177e4 LT |
346 | return 0; |
347 | ||
348 | /* Check the GUID Partition Table signature */ | |
349 | if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) { | |
d9916962 TG |
350 | pr_debug("GUID Partition Table Header signature is wrong:" |
351 | "%lld != %lld\n", | |
352 | (unsigned long long)le64_to_cpu((*gpt)->signature), | |
353 | (unsigned long long)GPT_HEADER_SIGNATURE); | |
1da177e4 LT |
354 | goto fail; |
355 | } | |
356 | ||
8b8a6e18 | 357 | /* Check the GUID Partition Table header size is too big */ |
3eb8e74e TW |
358 | if (le32_to_cpu((*gpt)->header_size) > |
359 | bdev_logical_block_size(state->bdev)) { | |
8b8a6e18 | 360 | pr_debug("GUID Partition Table Header size is too large: %u > %u\n", |
3eb8e74e TW |
361 | le32_to_cpu((*gpt)->header_size), |
362 | bdev_logical_block_size(state->bdev)); | |
363 | goto fail; | |
364 | } | |
365 | ||
8b8a6e18 PJ |
366 | /* Check the GUID Partition Table header size is too small */ |
367 | if (le32_to_cpu((*gpt)->header_size) < sizeof(gpt_header)) { | |
368 | pr_debug("GUID Partition Table Header size is too small: %u < %zu\n", | |
369 | le32_to_cpu((*gpt)->header_size), | |
370 | sizeof(gpt_header)); | |
371 | goto fail; | |
372 | } | |
373 | ||
1da177e4 LT |
374 | /* Check the GUID Partition Table CRC */ |
375 | origcrc = le32_to_cpu((*gpt)->header_crc32); | |
376 | (*gpt)->header_crc32 = 0; | |
377 | crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size)); | |
378 | ||
379 | if (crc != origcrc) { | |
d9916962 TG |
380 | pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n", |
381 | crc, origcrc); | |
1da177e4 LT |
382 | goto fail; |
383 | } | |
384 | (*gpt)->header_crc32 = cpu_to_le32(origcrc); | |
385 | ||
386 | /* Check that the my_lba entry points to the LBA that contains | |
387 | * the GUID Partition Table */ | |
388 | if (le64_to_cpu((*gpt)->my_lba) != lba) { | |
d9916962 TG |
389 | pr_debug("GPT my_lba incorrect: %lld != %lld\n", |
390 | (unsigned long long)le64_to_cpu((*gpt)->my_lba), | |
391 | (unsigned long long)lba); | |
1da177e4 LT |
392 | goto fail; |
393 | } | |
394 | ||
395 | /* Check the first_usable_lba and last_usable_lba are | |
396 | * within the disk. | |
397 | */ | |
1493bf21 | 398 | lastlba = last_lba(state->bdev); |
1da177e4 | 399 | if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) { |
d9916962 TG |
400 | pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n", |
401 | (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba), | |
402 | (unsigned long long)lastlba); | |
1da177e4 LT |
403 | goto fail; |
404 | } | |
405 | if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) { | |
d9916962 TG |
406 | pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", |
407 | (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), | |
408 | (unsigned long long)lastlba); | |
1da177e4 LT |
409 | goto fail; |
410 | } | |
aa054bc9 DB |
411 | if (le64_to_cpu((*gpt)->last_usable_lba) < le64_to_cpu((*gpt)->first_usable_lba)) { |
412 | pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", | |
413 | (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), | |
414 | (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba)); | |
415 | goto fail; | |
416 | } | |
fa039d5f TW |
417 | /* Check that sizeof_partition_entry has the correct value */ |
418 | if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) { | |
c19ca6cb | 419 | pr_debug("GUID Partition Entry Size check failed.\n"); |
fa039d5f TW |
420 | goto fail; |
421 | } | |
422 | ||
c5082b70 AT |
423 | /* Sanity check partition table size */ |
424 | pt_size = (u64)le32_to_cpu((*gpt)->num_partition_entries) * | |
425 | le32_to_cpu((*gpt)->sizeof_partition_entry); | |
426 | if (pt_size > KMALLOC_MAX_SIZE) { | |
427 | pr_debug("GUID Partition Table is too large: %llu > %lu bytes\n", | |
428 | (unsigned long long)pt_size, KMALLOC_MAX_SIZE); | |
429 | goto fail; | |
430 | } | |
431 | ||
1493bf21 | 432 | if (!(*ptes = alloc_read_gpt_entries(state, *gpt))) |
1da177e4 LT |
433 | goto fail; |
434 | ||
435 | /* Check the GUID Partition Entry Array CRC */ | |
c5082b70 | 436 | crc = efi_crc32((const unsigned char *) (*ptes), pt_size); |
1da177e4 LT |
437 | |
438 | if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) { | |
c19ca6cb | 439 | pr_debug("GUID Partition Entry Array CRC check failed.\n"); |
1da177e4 LT |
440 | goto fail_ptes; |
441 | } | |
442 | ||
443 | /* We're done, all's well */ | |
444 | return 1; | |
445 | ||
446 | fail_ptes: | |
447 | kfree(*ptes); | |
448 | *ptes = NULL; | |
449 | fail: | |
450 | kfree(*gpt); | |
451 | *gpt = NULL; | |
452 | return 0; | |
453 | } | |
454 | ||
455 | /** | |
456 | * is_pte_valid() - tests one PTE for validity | |
16e15565 FF |
457 | * @pte:pte to check |
458 | * @lastlba: last lba of the disk | |
1da177e4 LT |
459 | * |
460 | * Description: returns 1 if valid, 0 on error. | |
461 | */ | |
462 | static inline int | |
463 | is_pte_valid(const gpt_entry *pte, const u64 lastlba) | |
464 | { | |
465 | if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) || | |
466 | le64_to_cpu(pte->starting_lba) > lastlba || | |
467 | le64_to_cpu(pte->ending_lba) > lastlba) | |
468 | return 0; | |
469 | return 1; | |
470 | } | |
471 | ||
472 | /** | |
473 | * compare_gpts() - Search disk for valid GPT headers and PTEs | |
16e15565 FF |
474 | * @pgpt: primary GPT header |
475 | * @agpt: alternate GPT header | |
476 | * @lastlba: last LBA number | |
477 | * | |
1da177e4 LT |
478 | * Description: Returns nothing. Sanity checks pgpt and agpt fields |
479 | * and prints warnings on discrepancies. | |
480 | * | |
481 | */ | |
482 | static void | |
483 | compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba) | |
484 | { | |
485 | int error_found = 0; | |
486 | if (!pgpt || !agpt) | |
487 | return; | |
488 | if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) { | |
b4bc4a18 AM |
489 | pr_warn("GPT:Primary header LBA != Alt. header alternate_lba\n"); |
490 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
491 | (unsigned long long)le64_to_cpu(pgpt->my_lba), |
492 | (unsigned long long)le64_to_cpu(agpt->alternate_lba)); | |
493 | error_found++; | |
494 | } | |
495 | if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) { | |
b4bc4a18 AM |
496 | pr_warn("GPT:Primary header alternate_lba != Alt. header my_lba\n"); |
497 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
498 | (unsigned long long)le64_to_cpu(pgpt->alternate_lba), |
499 | (unsigned long long)le64_to_cpu(agpt->my_lba)); | |
500 | error_found++; | |
501 | } | |
502 | if (le64_to_cpu(pgpt->first_usable_lba) != | |
503 | le64_to_cpu(agpt->first_usable_lba)) { | |
b4bc4a18 AM |
504 | pr_warn("GPT:first_usable_lbas don't match.\n"); |
505 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
506 | (unsigned long long)le64_to_cpu(pgpt->first_usable_lba), |
507 | (unsigned long long)le64_to_cpu(agpt->first_usable_lba)); | |
508 | error_found++; | |
509 | } | |
510 | if (le64_to_cpu(pgpt->last_usable_lba) != | |
511 | le64_to_cpu(agpt->last_usable_lba)) { | |
b4bc4a18 AM |
512 | pr_warn("GPT:last_usable_lbas don't match.\n"); |
513 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
514 | (unsigned long long)le64_to_cpu(pgpt->last_usable_lba), |
515 | (unsigned long long)le64_to_cpu(agpt->last_usable_lba)); | |
516 | error_found++; | |
517 | } | |
518 | if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) { | |
b4bc4a18 | 519 | pr_warn("GPT:disk_guids don't match.\n"); |
1da177e4 LT |
520 | error_found++; |
521 | } | |
522 | if (le32_to_cpu(pgpt->num_partition_entries) != | |
523 | le32_to_cpu(agpt->num_partition_entries)) { | |
b4bc4a18 | 524 | pr_warn("GPT:num_partition_entries don't match: " |
1da177e4 LT |
525 | "0x%x != 0x%x\n", |
526 | le32_to_cpu(pgpt->num_partition_entries), | |
527 | le32_to_cpu(agpt->num_partition_entries)); | |
528 | error_found++; | |
529 | } | |
530 | if (le32_to_cpu(pgpt->sizeof_partition_entry) != | |
531 | le32_to_cpu(agpt->sizeof_partition_entry)) { | |
b4bc4a18 | 532 | pr_warn("GPT:sizeof_partition_entry values don't match: " |
1da177e4 LT |
533 | "0x%x != 0x%x\n", |
534 | le32_to_cpu(pgpt->sizeof_partition_entry), | |
535 | le32_to_cpu(agpt->sizeof_partition_entry)); | |
536 | error_found++; | |
537 | } | |
538 | if (le32_to_cpu(pgpt->partition_entry_array_crc32) != | |
539 | le32_to_cpu(agpt->partition_entry_array_crc32)) { | |
b4bc4a18 | 540 | pr_warn("GPT:partition_entry_array_crc32 values don't match: " |
1da177e4 LT |
541 | "0x%x != 0x%x\n", |
542 | le32_to_cpu(pgpt->partition_entry_array_crc32), | |
543 | le32_to_cpu(agpt->partition_entry_array_crc32)); | |
544 | error_found++; | |
545 | } | |
546 | if (le64_to_cpu(pgpt->alternate_lba) != lastlba) { | |
b4bc4a18 AM |
547 | pr_warn("GPT:Primary header thinks Alt. header is not at the end of the disk.\n"); |
548 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
549 | (unsigned long long)le64_to_cpu(pgpt->alternate_lba), |
550 | (unsigned long long)lastlba); | |
551 | error_found++; | |
552 | } | |
553 | ||
554 | if (le64_to_cpu(agpt->my_lba) != lastlba) { | |
b4bc4a18 AM |
555 | pr_warn("GPT:Alternate GPT header not at the end of the disk.\n"); |
556 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
557 | (unsigned long long)le64_to_cpu(agpt->my_lba), |
558 | (unsigned long long)lastlba); | |
559 | error_found++; | |
560 | } | |
561 | ||
562 | if (error_found) | |
b4bc4a18 | 563 | pr_warn("GPT: Use GNU Parted to correct GPT errors.\n"); |
1da177e4 LT |
564 | return; |
565 | } | |
566 | ||
567 | /** | |
568 | * find_valid_gpt() - Search disk for valid GPT headers and PTEs | |
16e15565 FF |
569 | * @state: disk parsed partitions |
570 | * @gpt: GPT header ptr, filled on return. | |
571 | * @ptes: PTEs ptr, filled on return. | |
572 | * | |
1da177e4 LT |
573 | * Description: Returns 1 if valid, 0 on error. |
574 | * If valid, returns pointers to newly allocated GPT header and PTEs. | |
575 | * Validity depends on PMBR being valid (or being overridden by the | |
576 | * 'gpt' kernel command line option) and finding either the Primary | |
577 | * GPT header and PTEs valid, or the Alternate GPT header and PTEs | |
578 | * valid. If the Primary GPT header is not valid, the Alternate GPT header | |
579 | * is not checked unless the 'gpt' kernel command line option is passed. | |
580 | * This protects against devices which misreport their size, and forces | |
581 | * the user to decide to use the Alternate GPT. | |
582 | */ | |
1493bf21 TH |
583 | static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt, |
584 | gpt_entry **ptes) | |
1da177e4 LT |
585 | { |
586 | int good_pgpt = 0, good_agpt = 0, good_pmbr = 0; | |
587 | gpt_header *pgpt = NULL, *agpt = NULL; | |
588 | gpt_entry *pptes = NULL, *aptes = NULL; | |
4c64c30a | 589 | legacy_mbr *legacymbr; |
27a7c642 | 590 | sector_t total_sectors = i_size_read(state->bdev->bd_inode) >> 9; |
1da177e4 | 591 | u64 lastlba; |
1493bf21 TH |
592 | |
593 | if (!ptes) | |
1da177e4 LT |
594 | return 0; |
595 | ||
1493bf21 | 596 | lastlba = last_lba(state->bdev); |
1da177e4 | 597 | if (!force_gpt) { |
b05ebbbb DB |
598 | /* This will be added to the EFI Spec. per Intel after v1.02. */ |
599 | legacymbr = kzalloc(sizeof(*legacymbr), GFP_KERNEL); | |
600 | if (!legacymbr) | |
601 | goto fail; | |
602 | ||
603 | read_lba(state, 0, (u8 *)legacymbr, sizeof(*legacymbr)); | |
27a7c642 | 604 | good_pmbr = is_pmbr_valid(legacymbr, total_sectors); |
b05ebbbb DB |
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 | } | |
1da177e4 | 614 | |
1493bf21 | 615 | good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA, |
1da177e4 LT |
616 | &pgpt, &pptes); |
617 | if (good_pgpt) | |
1493bf21 | 618 | good_agpt = is_gpt_valid(state, |
1da177e4 LT |
619 | le64_to_cpu(pgpt->alternate_lba), |
620 | &agpt, &aptes); | |
621 | if (!good_agpt && force_gpt) | |
1493bf21 | 622 | good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes); |
1da177e4 LT |
623 | |
624 | /* The obviously unsuccessful case */ | |
625 | if (!good_pgpt && !good_agpt) | |
626 | goto fail; | |
627 | ||
628 | compare_gpts(pgpt, agpt, lastlba); | |
629 | ||
630 | /* The good cases */ | |
631 | if (good_pgpt) { | |
632 | *gpt = pgpt; | |
633 | *ptes = pptes; | |
634 | kfree(agpt); | |
635 | kfree(aptes); | |
70f637e9 | 636 | if (!good_agpt) |
b4bc4a18 | 637 | pr_warn("Alternate GPT is invalid, using primary GPT.\n"); |
1da177e4 LT |
638 | return 1; |
639 | } | |
640 | else if (good_agpt) { | |
641 | *gpt = agpt; | |
642 | *ptes = aptes; | |
643 | kfree(pgpt); | |
644 | kfree(pptes); | |
b4bc4a18 | 645 | pr_warn("Primary GPT is invalid, using alternate GPT.\n"); |
1da177e4 LT |
646 | return 1; |
647 | } | |
648 | ||
649 | fail: | |
650 | kfree(pgpt); | |
651 | kfree(agpt); | |
652 | kfree(pptes); | |
653 | kfree(aptes); | |
654 | *gpt = NULL; | |
655 | *ptes = NULL; | |
656 | return 0; | |
657 | } | |
658 | ||
659 | /** | |
1493bf21 | 660 | * efi_partition(struct parsed_partitions *state) |
16e15565 | 661 | * @state: disk parsed partitions |
1da177e4 LT |
662 | * |
663 | * Description: called from check.c, if the disk contains GPT | |
664 | * partitions, sets up partition entries in the kernel. | |
665 | * | |
666 | * If the first block on the disk is a legacy MBR, | |
667 | * it will get handled by msdos_partition(). | |
668 | * If it's a Protective MBR, we'll handle it here. | |
669 | * | |
670 | * We do not create a Linux partition for GPT, but | |
671 | * only for the actual data partitions. | |
672 | * Returns: | |
673 | * -1 if unable to read the partition table | |
674 | * 0 if this isn't our partition table | |
675 | * 1 if successful | |
676 | * | |
677 | */ | |
1493bf21 | 678 | int efi_partition(struct parsed_partitions *state) |
1da177e4 LT |
679 | { |
680 | gpt_header *gpt = NULL; | |
681 | gpt_entry *ptes = NULL; | |
682 | u32 i; | |
1493bf21 | 683 | unsigned ssz = bdev_logical_block_size(state->bdev) / 512; |
1da177e4 | 684 | |
1493bf21 | 685 | if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) { |
1da177e4 LT |
686 | kfree(gpt); |
687 | kfree(ptes); | |
688 | return 0; | |
689 | } | |
690 | ||
d9916962 | 691 | pr_debug("GUID Partition Table is valid! Yea!\n"); |
1da177e4 LT |
692 | |
693 | for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) { | |
eec7ecfe WD |
694 | struct partition_meta_info *info; |
695 | unsigned label_count = 0; | |
696 | unsigned label_max; | |
7d13af32 KZ |
697 | u64 start = le64_to_cpu(ptes[i].starting_lba); |
698 | u64 size = le64_to_cpu(ptes[i].ending_lba) - | |
699 | le64_to_cpu(ptes[i].starting_lba) + 1ULL; | |
700 | ||
1493bf21 | 701 | if (!is_pte_valid(&ptes[i], last_lba(state->bdev))) |
1da177e4 LT |
702 | continue; |
703 | ||
7d13af32 | 704 | put_partition(state, i+1, start * ssz, size * ssz); |
1da177e4 LT |
705 | |
706 | /* If this is a RAID volume, tell md */ | |
70f637e9 | 707 | if (!efi_guidcmp(ptes[i].partition_type_guid, PARTITION_LINUX_RAID_GUID)) |
cc910624 | 708 | state->parts[i + 1].flags = ADDPART_FLAG_RAID; |
eec7ecfe WD |
709 | |
710 | info = &state->parts[i + 1].info; | |
26e02272 | 711 | efi_guid_to_str(&ptes[i].unique_partition_guid, info->uuid); |
eec7ecfe WD |
712 | |
713 | /* Naively convert UTF16-LE to 7 bits. */ | |
49204c11 AM |
714 | label_max = min(ARRAY_SIZE(info->volname) - 1, |
715 | ARRAY_SIZE(ptes[i].partition_name)); | |
eec7ecfe WD |
716 | info->volname[label_max] = 0; |
717 | while (label_count < label_max) { | |
718 | u8 c = ptes[i].partition_name[label_count] & 0xff; | |
719 | if (c && !isprint(c)) | |
720 | c = '!'; | |
721 | info->volname[label_count] = c; | |
722 | label_count++; | |
723 | } | |
724 | state->parts[i + 1].has_info = true; | |
1da177e4 LT |
725 | } |
726 | kfree(ptes); | |
727 | kfree(gpt); | |
9c867fbe | 728 | strlcat(state->pp_buf, "\n", PAGE_SIZE); |
1da177e4 LT |
729 | return 1; |
730 | } |