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1// SPDX-License-Identifier: GPL-2.0-or-later2/************************************************************3 * EFI GUID Partition Table handling4 *5 * http://www.uefi.org/specs/6 * http://www.intel.com/technology/efi/7 *8 * efi.[ch] by Matt Domsch <Matt_Domsch@dell.com>9 *   Copyright 2000,2001,2002,2004 Dell Inc.10 *11 * TODO:12 *13 * Changelog:14 * Mon August 5th, 2013 Davidlohr Bueso <davidlohr@hp.com>15 * - detect hybrid MBRs, tighter pMBR checking & cleanups.16 *17 * Mon Nov 09 2004 Matt Domsch <Matt_Domsch@dell.com>18 * - test for valid PMBR and valid PGPT before ever reading19 *   AGPT, allow override with 'gpt' kernel command line option.20 * - check for first/last_usable_lba outside of size of disk21 *22 * Tue  Mar 26 2002 Matt Domsch <Matt_Domsch@dell.com>23 * - Ported to 2.5.7-pre1 and 2.5.7-dj224 * - Applied patch to avoid fault in alternate header handling25 * - cleaned up find_valid_gpt26 * - On-disk structure and copy in memory is *always* LE now - 27 *   swab fields as needed28 * - remove print_gpt_header()29 * - only use first max_p partition entries, to keep the kernel minor number30 *   and partition numbers tied.31 *32 * Mon  Feb 04 2002 Matt Domsch <Matt_Domsch@dell.com>33 * - Removed __PRIPTR_PREFIX - not being used34 *35 * Mon  Jan 14 2002 Matt Domsch <Matt_Domsch@dell.com>36 * - Ported to 2.5.2-pre11 + library crc32 patch Linus applied37 *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 only41 *   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 Wilck46 *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 architectures53 * - fixed debug_printk(), now Dprintk()54 *55 * Mon Oct 01 2001 Matt Domsch <Matt_Domsch@dell.com>56 * - Style cleanups57 * - made most functions static58 * - Endianness addition59 * - 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 last61 *   sector of an odd-sized disk from user space.  No tools have ever62 *   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) for68 *   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 equivalent75 *   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 block79 *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 ************************************************************/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/* This allows a kernel command line option 'gpt' to override94 * the test for invalid PMBR.  Not __initdata because reloading95 * the partition tables happens after init too.96 */97static int force_gpt;98static int __init99force_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 function109 * @buf: buffer to calculate crc32 of110 * @len: length of buf111 *112 * Description: Returns EFI-style CRC32 value for @buf113 * 114 * This function uses the little endian Ethernet polynomial115 * but seeds the function with ~0, and xor's with ~0 at the end.116 * Note, the EFI Specification, v1.02, has a reference to117 * Dr. Dobbs Journal, May 1994 (actually it's in May 1992).118 */119static inline u32120efi_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 device127 * @disk: block device128 * 129 * Description: Returns last LBA value on success, 0 on error.130 * This is stored (by sd and ide-geometry) in131 *  the part[0] entry for this disk, and is the number of132 *  physical sectors available on the disk.133 */134static u64 last_lba(struct gendisk *disk)135{136	return div_u64(bdev_nr_bytes(disk->part0),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	/* 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;148 149	return GPT_MBR_PROTECTIVE;150invalid:151	return 0;152}153 154/**155 * is_pmbr_valid(): test Protective MBR for validity156 * @mbr: pointer to a legacy mbr structure157 * @total_sectors: amount of sectors in the device158 *159 * Description: Checks for a valid protective or hybrid160 * master boot record (MBR). The validity of a pMBR depends161 * on all of the following properties:162 *  1) MSDOS signature is in the last two bytes of the MBR163 *  2) One partition of type 0xEE is found164 *165 * In addition, a hybrid MBR will have up to three additional166 * primary partitions, which point to the same space that's167 * marked out by up to three GPT partitions.168 *169 * Returns 0 upon invalid MBR, or GPT_MBR_PROTECTIVE or170 * GPT_MBR_HYBRID depending on the device layout.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; /* invalid by default */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			 * Ok, we at least know that there's a protective MBR,186			 * now check if there are other partition types for187			 * hybrid MBR.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	 * Protective MBRs take up the lesser of the whole disk204	 * or 2 TiB (32bit LBA), ignoring the rest of the disk.205	 * Some partitioning programs, nonetheless, choose to set206	 * the size to the maximum 32-bit limitation, disregarding207	 * the disk size.208	 *209	 * Hybrid MBRs do not necessarily comply with this.210	 *211	 * Consider a bad value here to be a warning to support dd'ing212	 * an image from a smaller disk to a larger disk.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 * read_lba(): Read bytes from disk, starting at given LBA227 * @state: disk parsed partitions228 * @lba: the Logical Block Address of the partition table229 * @buffer: destination buffer230 * @count: bytes to read231 *232 * Description: Reads @count bytes from @state->disk into @buffer.233 * Returns number of bytes read on success, 0 on error.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++, &sect);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 disk264 * @state: disk parsed partitions265 * @gpt: GPT header266 * 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 */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 * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk299 * @state: disk parsed partitions300 * @lba: the Logical Block Address of the partition table301 * 302 * Description: returns GPT header on success, NULL on error.   Allocates303 * and fills a GPT header starting at @ from @state->disk.304 * Note: remember to free gpt when finished with it.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 * is_gpt_valid() - tests one GPT header and PTEs for validity327 * @state: disk parsed partitions328 * @lba: logical block address of the GPT header to test329 * @gpt: GPT header ptr, filled on return.330 * @ptes: PTEs ptr, filled on return.331 *332 * Description: returns 1 if valid,  0 on error.333 * If valid, returns pointers to newly allocated GPT header and PTEs.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	/* Check the GUID Partition Table signature */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	/* Check the GUID Partition Table header size is too big */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	/* 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	}371 372	/* 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) {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	/* Check that the my_lba entry points to the LBA that contains385	 * the GUID Partition Table */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	/* Check the first_usable_lba and last_usable_lba are394	 * within the disk.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	/* Check that sizeof_partition_entry has the correct value */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	/* 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	}429 430	if (!(*ptes = alloc_read_gpt_entries(state, *gpt)))431		goto fail;432 433	/* Check the GUID Partition Entry Array CRC */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	/* 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 validity455 * @pte:pte to check456 * @lastlba: last lba of the disk457 *458 * Description: returns 1 if valid,  0 on error.459 */460static inline int461is_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 PTEs472 * @pgpt: primary GPT header473 * @agpt: alternate GPT header474 * @lastlba: last LBA number475 *476 * Description: Returns nothing.  Sanity checks pgpt and agpt fields477 * and prints warnings on discrepancies.478 * 479 */480static void481compare_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/**566 * find_valid_gpt() - Search disk for valid GPT headers and PTEs567 * @state: disk parsed partitions568 * @gpt: GPT header ptr, filled on return.569 * @ptes: PTEs ptr, filled on return.570 *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 the574 * 'gpt' kernel command line option) and finding either the Primary575 * GPT header and PTEs valid, or the Alternate GPT header and PTEs576 * valid.  If the Primary GPT header is not valid, the Alternate GPT header577 * is not checked unless the 'gpt' kernel command line option is passed.578 * This protects against devices which misreport their size, and forces579 * the user to decide to use the Alternate GPT.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		/* 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));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        /* 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);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}668 669/**670 * utf16_le_to_7bit(): Naively converts a UTF-16LE string to 7-bit ASCII characters671 * @in: input UTF-16LE string672 * @size: size of the input string673 * @out: output string ptr, should be capable to store @size+1 characters674 *675 * Description: Converts @size UTF16-LE symbols from @in string to 7-bit676 * ASCII characters and stores them to @out. Adds trailing zero to @out array.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}693 694/**695 * efi_partition - scan for GPT partitions696 * @state: disk parsed partitions697 *698 * Description: called from check.c, if the disk contains GPT699 * 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, but706 * only for the actual data partitions.707 * Returns:708 * -1 if unable to read the partition table709 *  0 if this isn't our partition table710 *  1 if successful711 *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		/* If this is a RAID volume, tell md */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		/* Naively convert UTF16-LE to 7 bits. */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