Commit | Line | Data |
---|---|---|
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 | |
a08aa9bc | 127 | * @disk: block device |
1da177e4 LT |
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 | */ | |
a08aa9bc | 134 | static u64 last_lba(struct gendisk *disk) |
1da177e4 | 135 | { |
f9831b88 | 136 | return div_u64(bdev_nr_bytes(disk->part0), |
a08aa9bc | 137 | queue_logical_block_size(disk->queue)) - 1ULL; |
1da177e4 LT |
138 | } |
139 | ||
c2ebdc24 | 140 | static inline int pmbr_part_valid(gpt_mbr_record *part) |
1da177e4 | 141 | { |
33afd7a7 DB |
142 | if (part->os_type != EFI_PMBR_OSTYPE_EFI_GPT) |
143 | goto invalid; | |
144 | ||
145 | /* set to 0x00000001 (i.e., the LBA of the GPT Partition Header) */ | |
146 | if (le32_to_cpu(part->starting_lba) != GPT_PRIMARY_PARTITION_TABLE_LBA) | |
147 | goto invalid; | |
148 | ||
b05ebbbb | 149 | return GPT_MBR_PROTECTIVE; |
33afd7a7 DB |
150 | invalid: |
151 | return 0; | |
1da177e4 LT |
152 | } |
153 | ||
154 | /** | |
155 | * is_pmbr_valid(): test Protective MBR for validity | |
156 | * @mbr: pointer to a legacy mbr structure | |
27a7c642 | 157 | * @total_sectors: amount of sectors in the device |
1da177e4 | 158 | * |
b05ebbbb DB |
159 | * Description: Checks for a valid protective or hybrid |
160 | * master boot record (MBR). The validity of a pMBR depends | |
161 | * on all of the following properties: | |
1da177e4 LT |
162 | * 1) MSDOS signature is in the last two bytes of the MBR |
163 | * 2) One partition of type 0xEE is found | |
b05ebbbb DB |
164 | * |
165 | * In addition, a hybrid MBR will have up to three additional | |
166 | * primary partitions, which point to the same space that's | |
167 | * marked out by up to three GPT partitions. | |
168 | * | |
169 | * Returns 0 upon invalid MBR, or GPT_MBR_PROTECTIVE or | |
170 | * GPT_MBR_HYBRID depending on the device layout. | |
1da177e4 | 171 | */ |
27a7c642 | 172 | static int is_pmbr_valid(legacy_mbr *mbr, sector_t total_sectors) |
1da177e4 | 173 | { |
6b02fa59 | 174 | uint32_t sz = 0; |
27a7c642 | 175 | int i, part = 0, ret = 0; /* invalid by default */ |
b05ebbbb | 176 | |
1da177e4 | 177 | if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE) |
b05ebbbb DB |
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) { | |
27a7c642 | 183 | part = i; |
b05ebbbb DB |
184 | /* |
185 | * Ok, we at least know that there's a protective MBR, | |
186 | * now check if there are other partition types for | |
187 | * hybrid MBR. | |
188 | */ | |
189 | goto check_hybrid; | |
190 | } | |
191 | } | |
192 | ||
193 | if (ret != GPT_MBR_PROTECTIVE) | |
194 | goto done; | |
195 | check_hybrid: | |
1da177e4 | 196 | for (i = 0; i < 4; i++) |
b05ebbbb DB |
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; | |
27a7c642 DB |
201 | |
202 | /* | |
203 | * Protective MBRs take up the lesser of the whole disk | |
204 | * or 2 TiB (32bit LBA), ignoring the rest of the disk. | |
6b02fa59 DB |
205 | * Some partitioning programs, nonetheless, choose to set |
206 | * the size to the maximum 32-bit limitation, disregarding | |
207 | * the disk size. | |
27a7c642 DB |
208 | * |
209 | * Hybrid MBRs do not necessarily comply with this. | |
87fc0ad2 DA |
210 | * |
211 | * Consider a bad value here to be a warning to support dd'ing | |
212 | * an image from a smaller disk to a larger disk. | |
27a7c642 DB |
213 | */ |
214 | if (ret == GPT_MBR_PROTECTIVE) { | |
6b02fa59 DB |
215 | sz = le32_to_cpu(mbr->partition_record[part].size_in_lba); |
216 | if (sz != (uint32_t) total_sectors - 1 && sz != 0xFFFFFFFF) | |
87fc0ad2 DA |
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)); | |
27a7c642 | 220 | } |
b05ebbbb DB |
221 | done: |
222 | return ret; | |
1da177e4 LT |
223 | } |
224 | ||
225 | /** | |
226 | * read_lba(): Read bytes from disk, starting at given LBA | |
16e15565 FF |
227 | * @state: disk parsed partitions |
228 | * @lba: the Logical Block Address of the partition table | |
229 | * @buffer: destination buffer | |
230 | * @count: bytes to read | |
1da177e4 | 231 | * |
a08aa9bc | 232 | * Description: Reads @count bytes from @state->disk into @buffer. |
1da177e4 LT |
233 | * Returns number of bytes read on success, 0 on error. |
234 | */ | |
1493bf21 TH |
235 | static size_t read_lba(struct parsed_partitions *state, |
236 | u64 lba, u8 *buffer, size_t count) | |
1da177e4 LT |
237 | { |
238 | size_t totalreadcount = 0; | |
a08aa9bc CH |
239 | sector_t n = lba * |
240 | (queue_logical_block_size(state->disk->queue) / 512); | |
1da177e4 | 241 | |
a08aa9bc | 242 | if (!buffer || lba > last_lba(state->disk)) |
1da177e4 LT |
243 | return 0; |
244 | ||
245 | while (count) { | |
246 | int copied = 512; | |
247 | Sector sect; | |
1493bf21 | 248 | unsigned char *data = read_part_sector(state, n++, §); |
1da177e4 LT |
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 | * alloc_read_gpt_entries(): reads partition entries from disk | |
16e15565 FF |
264 | * @state: disk parsed partitions |
265 | * @gpt: GPT header | |
1da177e4 LT |
266 | * |
267 | * Description: Returns ptes on success, NULL on error. | |
268 | * Allocates space for PTEs based on information found in @gpt. | |
269 | * Notes: remember to free pte when you're done! | |
270 | */ | |
1493bf21 TH |
271 | static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state, |
272 | gpt_header *gpt) | |
1da177e4 LT |
273 | { |
274 | size_t count; | |
275 | gpt_entry *pte; | |
1493bf21 TH |
276 | |
277 | if (!gpt) | |
1da177e4 LT |
278 | return NULL; |
279 | ||
c5082b70 | 280 | count = (size_t)le32_to_cpu(gpt->num_partition_entries) * |
1da177e4 LT |
281 | le32_to_cpu(gpt->sizeof_partition_entry); |
282 | if (!count) | |
283 | return NULL; | |
ea56505b | 284 | pte = kmalloc(count, GFP_KERNEL); |
1da177e4 LT |
285 | if (!pte) |
286 | return NULL; | |
1da177e4 | 287 | |
1493bf21 | 288 | if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba), |
70f637e9 | 289 | (u8 *) pte, count) < count) { |
1da177e4 LT |
290 | kfree(pte); |
291 | pte=NULL; | |
292 | return NULL; | |
293 | } | |
294 | return pte; | |
295 | } | |
296 | ||
297 | /** | |
298 | * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk | |
16e15565 FF |
299 | * @state: disk parsed partitions |
300 | * @lba: the Logical Block Address of the partition table | |
1da177e4 LT |
301 | * |
302 | * Description: returns GPT header on success, NULL on error. Allocates | |
a08aa9bc | 303 | * and fills a GPT header starting at @ from @state->disk. |
1da177e4 LT |
304 | * Note: remember to free gpt when finished with it. |
305 | */ | |
1493bf21 TH |
306 | static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state, |
307 | u64 lba) | |
1da177e4 LT |
308 | { |
309 | gpt_header *gpt; | |
a08aa9bc | 310 | unsigned ssz = queue_logical_block_size(state->disk->queue); |
1da177e4 | 311 | |
ea56505b | 312 | gpt = kmalloc(ssz, GFP_KERNEL); |
1da177e4 LT |
313 | if (!gpt) |
314 | return NULL; | |
1da177e4 | 315 | |
1493bf21 | 316 | if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) { |
1da177e4 LT |
317 | kfree(gpt); |
318 | gpt=NULL; | |
319 | return NULL; | |
320 | } | |
321 | ||
322 | return gpt; | |
323 | } | |
324 | ||
325 | /** | |
326 | * is_gpt_valid() - tests one GPT header and PTEs for validity | |
16e15565 FF |
327 | * @state: disk parsed partitions |
328 | * @lba: logical block address of the GPT header to test | |
329 | * @gpt: GPT header ptr, filled on return. | |
330 | * @ptes: PTEs ptr, filled on return. | |
1da177e4 LT |
331 | * |
332 | * Description: returns 1 if valid, 0 on error. | |
333 | * If valid, returns pointers to newly allocated GPT header and PTEs. | |
334 | */ | |
1493bf21 TH |
335 | static int is_gpt_valid(struct parsed_partitions *state, u64 lba, |
336 | gpt_header **gpt, gpt_entry **ptes) | |
1da177e4 LT |
337 | { |
338 | u32 crc, origcrc; | |
c5082b70 | 339 | u64 lastlba, pt_size; |
1da177e4 | 340 | |
1493bf21 | 341 | if (!ptes) |
1da177e4 | 342 | return 0; |
1493bf21 | 343 | if (!(*gpt = alloc_read_gpt_header(state, lba))) |
1da177e4 LT |
344 | return 0; |
345 | ||
346 | /* Check the GUID Partition Table signature */ | |
347 | if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) { | |
d9916962 TG |
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); | |
1da177e4 LT |
352 | goto fail; |
353 | } | |
354 | ||
8b8a6e18 | 355 | /* Check the GUID Partition Table header size is too big */ |
3eb8e74e | 356 | if (le32_to_cpu((*gpt)->header_size) > |
a08aa9bc | 357 | queue_logical_block_size(state->disk->queue)) { |
8b8a6e18 | 358 | pr_debug("GUID Partition Table Header size is too large: %u > %u\n", |
3eb8e74e | 359 | le32_to_cpu((*gpt)->header_size), |
a08aa9bc | 360 | queue_logical_block_size(state->disk->queue)); |
3eb8e74e TW |
361 | goto fail; |
362 | } | |
363 | ||
8b8a6e18 PJ |
364 | /* Check the GUID Partition Table header size is too small */ |
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 | ||
1da177e4 LT |
372 | /* Check the GUID Partition Table CRC */ |
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) { | |
d9916962 TG |
378 | pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n", |
379 | crc, origcrc); | |
1da177e4 LT |
380 | goto fail; |
381 | } | |
382 | (*gpt)->header_crc32 = cpu_to_le32(origcrc); | |
383 | ||
384 | /* Check that the my_lba entry points to the LBA that contains | |
385 | * the GUID Partition Table */ | |
386 | if (le64_to_cpu((*gpt)->my_lba) != lba) { | |
d9916962 TG |
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); | |
1da177e4 LT |
390 | goto fail; |
391 | } | |
392 | ||
393 | /* Check the first_usable_lba and last_usable_lba are | |
394 | * within the disk. | |
395 | */ | |
a08aa9bc | 396 | lastlba = last_lba(state->disk); |
1da177e4 | 397 | if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) { |
d9916962 TG |
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); | |
1da177e4 LT |
401 | goto fail; |
402 | } | |
403 | if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) { | |
d9916962 TG |
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); | |
1da177e4 LT |
407 | goto fail; |
408 | } | |
aa054bc9 DB |
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 | } | |
fa039d5f TW |
415 | /* Check that sizeof_partition_entry has the correct value */ |
416 | if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) { | |
c19ca6cb | 417 | pr_debug("GUID Partition Entry Size check failed.\n"); |
fa039d5f TW |
418 | goto fail; |
419 | } | |
420 | ||
c5082b70 AT |
421 | /* Sanity check partition table size */ |
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 | ||
1493bf21 | 430 | if (!(*ptes = alloc_read_gpt_entries(state, *gpt))) |
1da177e4 LT |
431 | goto fail; |
432 | ||
433 | /* Check the GUID Partition Entry Array CRC */ | |
c5082b70 | 434 | crc = efi_crc32((const unsigned char *) (*ptes), pt_size); |
1da177e4 LT |
435 | |
436 | if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) { | |
c19ca6cb | 437 | pr_debug("GUID Partition Entry Array CRC check failed.\n"); |
1da177e4 LT |
438 | goto fail_ptes; |
439 | } | |
440 | ||
441 | /* We're done, all's well */ | |
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 | * is_pte_valid() - tests one PTE for validity | |
16e15565 FF |
455 | * @pte:pte to check |
456 | * @lastlba: last lba of the disk | |
1da177e4 LT |
457 | * |
458 | * Description: returns 1 if valid, 0 on error. | |
459 | */ | |
460 | static inline int | |
461 | is_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 | * compare_gpts() - Search disk for valid GPT headers and PTEs | |
16e15565 FF |
472 | * @pgpt: primary GPT header |
473 | * @agpt: alternate GPT header | |
474 | * @lastlba: last LBA number | |
475 | * | |
1da177e4 LT |
476 | * Description: Returns nothing. Sanity checks pgpt and agpt fields |
477 | * and prints warnings on discrepancies. | |
478 | * | |
479 | */ | |
480 | static void | |
481 | compare_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)) { | |
b4bc4a18 AM |
487 | pr_warn("GPT:Primary header LBA != Alt. header alternate_lba\n"); |
488 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
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)) { | |
b4bc4a18 AM |
494 | pr_warn("GPT:Primary header alternate_lba != Alt. header my_lba\n"); |
495 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
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)) { | |
b4bc4a18 AM |
502 | pr_warn("GPT:first_usable_lbas don't match.\n"); |
503 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
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)) { | |
b4bc4a18 AM |
510 | pr_warn("GPT:last_usable_lbas don't match.\n"); |
511 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
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)) { | |
b4bc4a18 | 517 | pr_warn("GPT:disk_guids don't match.\n"); |
1da177e4 LT |
518 | error_found++; |
519 | } | |
520 | if (le32_to_cpu(pgpt->num_partition_entries) != | |
521 | le32_to_cpu(agpt->num_partition_entries)) { | |
b4bc4a18 | 522 | pr_warn("GPT:num_partition_entries don't match: " |
1da177e4 LT |
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)) { | |
b4bc4a18 | 530 | pr_warn("GPT:sizeof_partition_entry values don't match: " |
1da177e4 LT |
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)) { | |
b4bc4a18 | 538 | pr_warn("GPT:partition_entry_array_crc32 values don't match: " |
1da177e4 LT |
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) { | |
b4bc4a18 AM |
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", | |
1da177e4 LT |
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) { | |
b4bc4a18 AM |
553 | pr_warn("GPT:Alternate GPT header not at the end of the disk.\n"); |
554 | pr_warn("GPT:%lld != %lld\n", | |
1da177e4 LT |
555 | (unsigned long long)le64_to_cpu(agpt->my_lba), |
556 | (unsigned long long)lastlba); | |
557 | error_found++; | |
558 | } | |
559 | ||
560 | if (error_found) | |
b4bc4a18 | 561 | pr_warn("GPT: Use GNU Parted to correct GPT errors.\n"); |
1da177e4 LT |
562 | return; |
563 | } | |
564 | ||
565 | /** | |
566 | * find_valid_gpt() - Search disk for valid GPT headers and PTEs | |
16e15565 FF |
567 | * @state: disk parsed partitions |
568 | * @gpt: GPT header ptr, filled on return. | |
569 | * @ptes: PTEs ptr, filled on return. | |
570 | * | |
1da177e4 LT |
571 | * Description: Returns 1 if valid, 0 on error. |
572 | * If valid, returns pointers to newly allocated GPT header and PTEs. | |
573 | * Validity depends on PMBR being valid (or being overridden by the | |
574 | * 'gpt' kernel command line option) and finding either the Primary | |
575 | * GPT header and PTEs valid, or the Alternate GPT header and PTEs | |
576 | * valid. If the Primary GPT header is not valid, the Alternate GPT header | |
577 | * is not checked unless the 'gpt' kernel command line option is passed. | |
578 | * This protects against devices which misreport their size, and forces | |
579 | * the user to decide to use the Alternate GPT. | |
580 | */ | |
1493bf21 TH |
581 | static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt, |
582 | gpt_entry **ptes) | |
1da177e4 LT |
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; | |
4c64c30a | 587 | legacy_mbr *legacymbr; |
466d9c49 DO |
588 | struct gendisk *disk = state->disk; |
589 | const struct block_device_operations *fops = disk->fops; | |
a08aa9bc | 590 | sector_t total_sectors = get_capacity(state->disk); |
1da177e4 | 591 | u64 lastlba; |
1493bf21 TH |
592 | |
593 | if (!ptes) | |
1da177e4 LT |
594 | return 0; |
595 | ||
a08aa9bc | 596 | lastlba = last_lba(state->disk); |
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 | 623 | |
466d9c49 DO |
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 | ||
1da177e4 LT |
634 | /* The obviously unsuccessful case */ |
635 | if (!good_pgpt && !good_agpt) | |
636 | goto fail; | |
637 | ||
638 | compare_gpts(pgpt, agpt, lastlba); | |
639 | ||
640 | /* The good cases */ | |
641 | if (good_pgpt) { | |
642 | *gpt = pgpt; | |
643 | *ptes = pptes; | |
644 | kfree(agpt); | |
645 | kfree(aptes); | |
70f637e9 | 646 | if (!good_agpt) |
b4bc4a18 | 647 | pr_warn("Alternate GPT is invalid, using primary GPT.\n"); |
1da177e4 LT |
648 | return 1; |
649 | } | |
650 | else if (good_agpt) { | |
651 | *gpt = agpt; | |
652 | *ptes = aptes; | |
653 | kfree(pgpt); | |
654 | kfree(pptes); | |
b4bc4a18 | 655 | pr_warn("Primary GPT is invalid, using alternate GPT.\n"); |
1da177e4 LT |
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 | ||
d5528d5e NM |
669 | /** |
670 | * utf16_le_to_7bit(): Naively converts a UTF-16LE string to 7-bit ASCII characters | |
671 | * @in: input UTF-16LE string | |
672 | * @size: size of the input string | |
673 | * @out: output string ptr, should be capable to store @size+1 characters | |
674 | * | |
675 | * Description: Converts @size UTF16-LE symbols from @in string to 7-bit | |
676 | * ASCII characters and stores them to @out. Adds trailing zero to @out array. | |
677 | */ | |
678 | static 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 | ||
1da177e4 | 694 | /** |
4bc20823 | 695 | * efi_partition - scan for GPT partitions |
16e15565 | 696 | * @state: disk parsed partitions |
1da177e4 LT |
697 | * |
698 | * Description: called from check.c, if the disk contains GPT | |
699 | * partitions, sets up partition entries in the kernel. | |
700 | * | |
701 | * If the first block on the disk is a legacy MBR, | |
702 | * it will get handled by msdos_partition(). | |
703 | * If it's a Protective MBR, we'll handle it here. | |
704 | * | |
705 | * We do not create a Linux partition for GPT, but | |
706 | * only for the actual data partitions. | |
707 | * Returns: | |
708 | * -1 if unable to read the partition table | |
709 | * 0 if this isn't our partition table | |
710 | * 1 if successful | |
711 | * | |
712 | */ | |
1493bf21 | 713 | int efi_partition(struct parsed_partitions *state) |
1da177e4 LT |
714 | { |
715 | gpt_header *gpt = NULL; | |
716 | gpt_entry *ptes = NULL; | |
717 | u32 i; | |
a08aa9bc | 718 | unsigned ssz = queue_logical_block_size(state->disk->queue) / 512; |
1da177e4 | 719 | |
1493bf21 | 720 | if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) { |
1da177e4 LT |
721 | kfree(gpt); |
722 | kfree(ptes); | |
723 | return 0; | |
724 | } | |
725 | ||
d9916962 | 726 | pr_debug("GUID Partition Table is valid! Yea!\n"); |
1da177e4 LT |
727 | |
728 | for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) { | |
eec7ecfe | 729 | struct partition_meta_info *info; |
eec7ecfe | 730 | unsigned label_max; |
7d13af32 KZ |
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 | ||
a08aa9bc | 735 | if (!is_pte_valid(&ptes[i], last_lba(state->disk))) |
1da177e4 LT |
736 | continue; |
737 | ||
7d13af32 | 738 | put_partition(state, i+1, start * ssz, size * ssz); |
1da177e4 LT |
739 | |
740 | /* If this is a RAID volume, tell md */ | |
70f637e9 | 741 | if (!efi_guidcmp(ptes[i].partition_type_guid, PARTITION_LINUX_RAID_GUID)) |
cc910624 | 742 | state->parts[i + 1].flags = ADDPART_FLAG_RAID; |
eec7ecfe WD |
743 | |
744 | info = &state->parts[i + 1].info; | |
26e02272 | 745 | efi_guid_to_str(&ptes[i].unique_partition_guid, info->uuid); |
eec7ecfe WD |
746 | |
747 | /* Naively convert UTF16-LE to 7 bits. */ | |
49204c11 AM |
748 | label_max = min(ARRAY_SIZE(info->volname) - 1, |
749 | ARRAY_SIZE(ptes[i].partition_name)); | |
d5528d5e | 750 | utf16_le_to_7bit(ptes[i].partition_name, label_max, info->volname); |
eec7ecfe | 751 | state->parts[i + 1].has_info = true; |
1da177e4 LT |
752 | } |
753 | kfree(ptes); | |
754 | kfree(gpt); | |
9c867fbe | 755 | strlcat(state->pp_buf, "\n", PAGE_SIZE); |
1da177e4 LT |
756 | return 1; |
757 | } |