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757 lines
23 KiB
757 lines
23 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/************************************************************ |
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* EFI GUID Partition Table handling |
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* |
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* http://www.uefi.org/specs/ |
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* http://www.intel.com/technology/efi/ |
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* |
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* efi.[ch] by Matt Domsch <[email protected]> |
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* Copyright 2000,2001,2002,2004 Dell Inc. |
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* |
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* TODO: |
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* |
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* Changelog: |
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* Mon August 5th, 2013 Davidlohr Bueso <[email protected]> |
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* - detect hybrid MBRs, tighter pMBR checking & cleanups. |
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* |
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* Mon Nov 09 2004 Matt Domsch <[email protected]> |
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* - test for valid PMBR and valid PGPT before ever reading |
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* AGPT, allow override with 'gpt' kernel command line option. |
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* - check for first/last_usable_lba outside of size of disk |
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* |
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* Tue Mar 26 2002 Matt Domsch <[email protected]> |
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* - Ported to 2.5.7-pre1 and 2.5.7-dj2 |
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* - Applied patch to avoid fault in alternate header handling |
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* - cleaned up find_valid_gpt |
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* - On-disk structure and copy in memory is *always* LE now - |
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* swab fields as needed |
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* - remove print_gpt_header() |
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* - only use first max_p partition entries, to keep the kernel minor number |
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* and partition numbers tied. |
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* |
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* Mon Feb 04 2002 Matt Domsch <[email protected]> |
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* - Removed __PRIPTR_PREFIX - not being used |
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* |
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* Mon Jan 14 2002 Matt Domsch <[email protected]> |
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* - Ported to 2.5.2-pre11 + library crc32 patch Linus applied |
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* |
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* Thu Dec 6 2001 Matt Domsch <[email protected]> |
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* - Added compare_gpts(). |
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* - moved le_efi_guid_to_cpus() back into this file. GPT is the only |
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* thing that keeps EFI GUIDs on disk. |
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* - Changed gpt structure names and members to be simpler and more Linux-like. |
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* |
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* Wed Oct 17 2001 Matt Domsch <[email protected]> |
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* - Removed CONFIG_DEVFS_VOLUMES_UUID code entirely per Martin Wilck |
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* |
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* Wed Oct 10 2001 Matt Domsch <[email protected]> |
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* - Changed function comments to DocBook style per Andreas Dilger suggestion. |
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* |
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* Mon Oct 08 2001 Matt Domsch <[email protected]> |
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* - Change read_lba() to use the page cache per Al Viro's work. |
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* - print u64s properly on all architectures |
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* - fixed debug_printk(), now Dprintk() |
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* |
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* Mon Oct 01 2001 Matt Domsch <[email protected]> |
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* - Style cleanups |
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* - made most functions static |
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* - Endianness addition |
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* - remove test for second alternate header, as it's not per spec, |
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* and is unnecessary. There's now a method to read/write the last |
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* sector of an odd-sized disk from user space. No tools have ever |
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* been released which used this code, so it's effectively dead. |
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* - Per Asit Mallick of Intel, added a test for a valid PMBR. |
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* - Added kernel command line option 'gpt' to override valid PMBR test. |
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* |
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* Wed Jun 6 2001 Martin Wilck <[email protected]> |
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* - added devfs volume UUID support (/dev/volumes/uuids) for |
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* mounting file systems by the partition GUID. |
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* |
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* Tue Dec 5 2000 Matt Domsch <[email protected]> |
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* - Moved crc32() to linux/lib, added efi_crc32(). |
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* |
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* Thu Nov 30 2000 Matt Domsch <[email protected]> |
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* - Replaced Intel's CRC32 function with an equivalent |
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* non-license-restricted version. |
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* |
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* Wed Oct 25 2000 Matt Domsch <[email protected]> |
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* - Fixed the last_lba() call to return the proper last block |
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* |
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* Thu Oct 12 2000 Matt Domsch <[email protected]> |
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* - Thanks to Andries Brouwer for his debugging assistance. |
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* - Code works, detects all the partitions. |
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* |
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************************************************************/ |
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#include <linux/kernel.h> |
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#include <linux/crc32.h> |
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#include <linux/ctype.h> |
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#include <linux/math64.h> |
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#include <linux/slab.h> |
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#include "check.h" |
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#include "efi.h" |
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|
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/* This allows a kernel command line option 'gpt' to override |
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* the test for invalid PMBR. Not __initdata because reloading |
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* the partition tables happens after init too. |
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*/ |
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static int force_gpt; |
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static int __init |
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force_gpt_fn(char *str) |
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{ |
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force_gpt = 1; |
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return 1; |
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} |
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__setup("gpt", force_gpt_fn); |
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|
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|
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/** |
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* efi_crc32() - EFI version of crc32 function |
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* @buf: buffer to calculate crc32 of |
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* @len: length of buf |
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* |
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* Description: Returns EFI-style CRC32 value for @buf |
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* |
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* This function uses the little endian Ethernet polynomial |
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* but seeds the function with ~0, and xor's with ~0 at the end. |
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* Note, the EFI Specification, v1.02, has a reference to |
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* Dr. Dobbs Journal, May 1994 (actually it's in May 1992). |
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*/ |
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static inline u32 |
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efi_crc32(const void *buf, unsigned long len) |
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{ |
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return (crc32(~0L, buf, len) ^ ~0L); |
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} |
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|
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/** |
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* last_lba(): return number of last logical block of device |
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* @disk: block device |
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* |
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* Description: Returns last LBA value on success, 0 on error. |
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* This is stored (by sd and ide-geometry) in |
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* the part[0] entry for this disk, and is the number of |
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* physical sectors available on the disk. |
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*/ |
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static u64 last_lba(struct gendisk *disk) |
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{ |
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return div_u64(disk->part0->bd_inode->i_size, |
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queue_logical_block_size(disk->queue)) - 1ULL; |
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} |
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|
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static inline int pmbr_part_valid(gpt_mbr_record *part) |
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{ |
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if (part->os_type != EFI_PMBR_OSTYPE_EFI_GPT) |
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goto invalid; |
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|
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/* set to 0x00000001 (i.e., the LBA of the GPT Partition Header) */ |
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if (le32_to_cpu(part->starting_lba) != GPT_PRIMARY_PARTITION_TABLE_LBA) |
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goto invalid; |
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return GPT_MBR_PROTECTIVE; |
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invalid: |
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return 0; |
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} |
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|
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/** |
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* is_pmbr_valid(): test Protective MBR for validity |
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* @mbr: pointer to a legacy mbr structure |
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* @total_sectors: amount of sectors in the device |
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* |
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* Description: Checks for a valid protective or hybrid |
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* master boot record (MBR). The validity of a pMBR depends |
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* on all of the following properties: |
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* 1) MSDOS signature is in the last two bytes of the MBR |
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* 2) One partition of type 0xEE is found |
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* |
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* In addition, a hybrid MBR will have up to three additional |
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* primary partitions, which point to the same space that's |
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* marked out by up to three GPT partitions. |
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* |
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* Returns 0 upon invalid MBR, or GPT_MBR_PROTECTIVE or |
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* GPT_MBR_HYBRID depending on the device layout. |
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*/ |
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static int is_pmbr_valid(legacy_mbr *mbr, sector_t total_sectors) |
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{ |
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uint32_t sz = 0; |
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int i, part = 0, ret = 0; /* invalid by default */ |
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if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE) |
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goto done; |
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for (i = 0; i < 4; i++) { |
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ret = pmbr_part_valid(&mbr->partition_record[i]); |
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if (ret == GPT_MBR_PROTECTIVE) { |
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part = i; |
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/* |
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* Ok, we at least know that there's a protective MBR, |
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* now check if there are other partition types for |
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* hybrid MBR. |
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*/ |
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goto check_hybrid; |
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} |
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} |
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if (ret != GPT_MBR_PROTECTIVE) |
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goto done; |
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check_hybrid: |
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for (i = 0; i < 4; i++) |
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if ((mbr->partition_record[i].os_type != |
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EFI_PMBR_OSTYPE_EFI_GPT) && |
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(mbr->partition_record[i].os_type != 0x00)) |
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ret = GPT_MBR_HYBRID; |
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|
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/* |
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* Protective MBRs take up the lesser of the whole disk |
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* or 2 TiB (32bit LBA), ignoring the rest of the disk. |
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* Some partitioning programs, nonetheless, choose to set |
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* the size to the maximum 32-bit limitation, disregarding |
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* the disk size. |
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* |
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* Hybrid MBRs do not necessarily comply with this. |
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* |
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* Consider a bad value here to be a warning to support dd'ing |
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* an image from a smaller disk to a larger disk. |
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*/ |
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if (ret == GPT_MBR_PROTECTIVE) { |
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sz = le32_to_cpu(mbr->partition_record[part].size_in_lba); |
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if (sz != (uint32_t) total_sectors - 1 && sz != 0xFFFFFFFF) |
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pr_debug("GPT: mbr size in lba (%u) different than whole disk (%u).\n", |
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sz, min_t(uint32_t, |
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total_sectors - 1, 0xFFFFFFFF)); |
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} |
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done: |
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return ret; |
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} |
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|
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/** |
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* read_lba(): Read bytes from disk, starting at given LBA |
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* @state: disk parsed partitions |
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* @lba: the Logical Block Address of the partition table |
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* @buffer: destination buffer |
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* @count: bytes to read |
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* |
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* Description: Reads @count bytes from @state->disk into @buffer. |
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* Returns number of bytes read on success, 0 on error. |
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*/ |
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static size_t read_lba(struct parsed_partitions *state, |
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u64 lba, u8 *buffer, size_t count) |
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{ |
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size_t totalreadcount = 0; |
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sector_t n = lba * |
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(queue_logical_block_size(state->disk->queue) / 512); |
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if (!buffer || lba > last_lba(state->disk)) |
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return 0; |
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while (count) { |
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int copied = 512; |
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Sector sect; |
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unsigned char *data = read_part_sector(state, n++, §); |
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if (!data) |
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break; |
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if (copied > count) |
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copied = count; |
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memcpy(buffer, data, copied); |
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put_dev_sector(sect); |
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buffer += copied; |
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totalreadcount +=copied; |
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count -= copied; |
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} |
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return totalreadcount; |
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} |
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|
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/** |
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* alloc_read_gpt_entries(): reads partition entries from disk |
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* @state: disk parsed partitions |
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* @gpt: GPT header |
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* |
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* Description: Returns ptes on success, NULL on error. |
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* Allocates space for PTEs based on information found in @gpt. |
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* Notes: remember to free pte when you're done! |
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*/ |
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static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state, |
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gpt_header *gpt) |
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{ |
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size_t count; |
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gpt_entry *pte; |
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if (!gpt) |
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return NULL; |
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count = (size_t)le32_to_cpu(gpt->num_partition_entries) * |
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le32_to_cpu(gpt->sizeof_partition_entry); |
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if (!count) |
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return NULL; |
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pte = kmalloc(count, GFP_KERNEL); |
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if (!pte) |
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return NULL; |
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if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba), |
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(u8 *) pte, count) < count) { |
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kfree(pte); |
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pte=NULL; |
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return NULL; |
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} |
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return pte; |
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} |
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/** |
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* alloc_read_gpt_header(): Allocates GPT header, reads into it from disk |
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* @state: disk parsed partitions |
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* @lba: the Logical Block Address of the partition table |
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* |
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* Description: returns GPT header on success, NULL on error. Allocates |
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* and fills a GPT header starting at @ from @state->disk. |
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* Note: remember to free gpt when finished with it. |
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*/ |
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static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state, |
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u64 lba) |
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{ |
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gpt_header *gpt; |
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unsigned ssz = queue_logical_block_size(state->disk->queue); |
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gpt = kmalloc(ssz, GFP_KERNEL); |
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if (!gpt) |
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return NULL; |
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if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) { |
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kfree(gpt); |
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gpt=NULL; |
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return NULL; |
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} |
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return gpt; |
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} |
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|
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/** |
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* is_gpt_valid() - tests one GPT header and PTEs for validity |
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* @state: disk parsed partitions |
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* @lba: logical block address of the GPT header to test |
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* @gpt: GPT header ptr, filled on return. |
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* @ptes: PTEs ptr, filled on return. |
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* |
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* Description: returns 1 if valid, 0 on error. |
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* If valid, returns pointers to newly allocated GPT header and PTEs. |
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*/ |
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static int is_gpt_valid(struct parsed_partitions *state, u64 lba, |
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gpt_header **gpt, gpt_entry **ptes) |
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{ |
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u32 crc, origcrc; |
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u64 lastlba, pt_size; |
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if (!ptes) |
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return 0; |
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if (!(*gpt = alloc_read_gpt_header(state, lba))) |
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return 0; |
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|
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/* Check the GUID Partition Table signature */ |
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if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) { |
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pr_debug("GUID Partition Table Header signature is wrong:" |
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"%lld != %lld\n", |
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(unsigned long long)le64_to_cpu((*gpt)->signature), |
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(unsigned long long)GPT_HEADER_SIGNATURE); |
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goto fail; |
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} |
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|
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/* Check the GUID Partition Table header size is too big */ |
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if (le32_to_cpu((*gpt)->header_size) > |
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queue_logical_block_size(state->disk->queue)) { |
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pr_debug("GUID Partition Table Header size is too large: %u > %u\n", |
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le32_to_cpu((*gpt)->header_size), |
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queue_logical_block_size(state->disk->queue)); |
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goto fail; |
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} |
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|
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/* Check the GUID Partition Table header size is too small */ |
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if (le32_to_cpu((*gpt)->header_size) < sizeof(gpt_header)) { |
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pr_debug("GUID Partition Table Header size is too small: %u < %zu\n", |
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le32_to_cpu((*gpt)->header_size), |
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sizeof(gpt_header)); |
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goto fail; |
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} |
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|
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/* Check the GUID Partition Table CRC */ |
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origcrc = le32_to_cpu((*gpt)->header_crc32); |
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(*gpt)->header_crc32 = 0; |
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crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size)); |
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|
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if (crc != origcrc) { |
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pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n", |
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crc, origcrc); |
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goto fail; |
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} |
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(*gpt)->header_crc32 = cpu_to_le32(origcrc); |
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|
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/* Check that the my_lba entry points to the LBA that contains |
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* the GUID Partition Table */ |
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if (le64_to_cpu((*gpt)->my_lba) != lba) { |
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pr_debug("GPT my_lba incorrect: %lld != %lld\n", |
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(unsigned long long)le64_to_cpu((*gpt)->my_lba), |
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(unsigned long long)lba); |
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goto fail; |
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} |
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|
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/* Check the first_usable_lba and last_usable_lba are |
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* within the disk. |
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*/ |
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lastlba = last_lba(state->disk); |
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if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) { |
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pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n", |
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(unsigned long long)le64_to_cpu((*gpt)->first_usable_lba), |
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(unsigned long long)lastlba); |
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goto fail; |
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} |
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if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) { |
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pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", |
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(unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), |
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(unsigned long long)lastlba); |
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goto fail; |
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} |
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if (le64_to_cpu((*gpt)->last_usable_lba) < le64_to_cpu((*gpt)->first_usable_lba)) { |
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pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", |
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(unsigned long long)le64_to_cpu((*gpt)->last_usable_lba), |
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(unsigned long long)le64_to_cpu((*gpt)->first_usable_lba)); |
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goto fail; |
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} |
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/* Check that sizeof_partition_entry has the correct value */ |
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if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) { |
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pr_debug("GUID Partition Entry Size check failed.\n"); |
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goto fail; |
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} |
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|
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/* Sanity check partition table size */ |
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pt_size = (u64)le32_to_cpu((*gpt)->num_partition_entries) * |
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le32_to_cpu((*gpt)->sizeof_partition_entry); |
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if (pt_size > KMALLOC_MAX_SIZE) { |
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pr_debug("GUID Partition Table is too large: %llu > %lu bytes\n", |
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(unsigned long long)pt_size, KMALLOC_MAX_SIZE); |
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goto fail; |
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} |
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|
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if (!(*ptes = alloc_read_gpt_entries(state, *gpt))) |
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goto fail; |
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|
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/* Check the GUID Partition Entry Array CRC */ |
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crc = efi_crc32((const unsigned char *) (*ptes), pt_size); |
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|
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if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) { |
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pr_debug("GUID Partition Entry Array CRC check failed.\n"); |
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goto fail_ptes; |
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} |
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|
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/* We're done, all's well */ |
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return 1; |
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|
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fail_ptes: |
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kfree(*ptes); |
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*ptes = NULL; |
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fail: |
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kfree(*gpt); |
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*gpt = NULL; |
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return 0; |
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} |
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|
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/** |
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* is_pte_valid() - tests one PTE for validity |
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* @pte:pte to check |
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* @lastlba: last lba of the disk |
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* |
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* Description: returns 1 if valid, 0 on error. |
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*/ |
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static inline int |
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is_pte_valid(const gpt_entry *pte, const u64 lastlba) |
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{ |
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if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) || |
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le64_to_cpu(pte->starting_lba) > lastlba || |
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le64_to_cpu(pte->ending_lba) > lastlba) |
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return 0; |
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return 1; |
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} |
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|
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/** |
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* compare_gpts() - Search disk for valid GPT headers and PTEs |
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* @pgpt: primary GPT header |
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* @agpt: alternate GPT header |
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* @lastlba: last LBA number |
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* |
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* Description: Returns nothing. Sanity checks pgpt and agpt fields |
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* and prints warnings on discrepancies. |
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* |
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*/ |
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static void |
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compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba) |
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{ |
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int error_found = 0; |
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if (!pgpt || !agpt) |
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return; |
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if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) { |
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pr_warn("GPT:Primary header LBA != Alt. header alternate_lba\n"); |
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pr_warn("GPT:%lld != %lld\n", |
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(unsigned long long)le64_to_cpu(pgpt->my_lba), |
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(unsigned long long)le64_to_cpu(agpt->alternate_lba)); |
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error_found++; |
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} |
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if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) { |
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pr_warn("GPT:Primary header alternate_lba != Alt. header my_lba\n"); |
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pr_warn("GPT:%lld != %lld\n", |
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(unsigned long long)le64_to_cpu(pgpt->alternate_lba), |
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(unsigned long long)le64_to_cpu(agpt->my_lba)); |
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error_found++; |
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} |
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if (le64_to_cpu(pgpt->first_usable_lba) != |
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le64_to_cpu(agpt->first_usable_lba)) { |
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pr_warn("GPT:first_usable_lbas don't match.\n"); |
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pr_warn("GPT:%lld != %lld\n", |
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(unsigned long long)le64_to_cpu(pgpt->first_usable_lba), |
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(unsigned long long)le64_to_cpu(agpt->first_usable_lba)); |
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error_found++; |
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} |
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if (le64_to_cpu(pgpt->last_usable_lba) != |
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le64_to_cpu(agpt->last_usable_lba)) { |
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pr_warn("GPT:last_usable_lbas don't match.\n"); |
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pr_warn("GPT:%lld != %lld\n", |
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(unsigned long long)le64_to_cpu(pgpt->last_usable_lba), |
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(unsigned long long)le64_to_cpu(agpt->last_usable_lba)); |
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error_found++; |
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} |
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if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) { |
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pr_warn("GPT:disk_guids don't match.\n"); |
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error_found++; |
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} |
|
if (le32_to_cpu(pgpt->num_partition_entries) != |
|
le32_to_cpu(agpt->num_partition_entries)) { |
|
pr_warn("GPT:num_partition_entries don't match: " |
|
"0x%x != 0x%x\n", |
|
le32_to_cpu(pgpt->num_partition_entries), |
|
le32_to_cpu(agpt->num_partition_entries)); |
|
error_found++; |
|
} |
|
if (le32_to_cpu(pgpt->sizeof_partition_entry) != |
|
le32_to_cpu(agpt->sizeof_partition_entry)) { |
|
pr_warn("GPT:sizeof_partition_entry values don't match: " |
|
"0x%x != 0x%x\n", |
|
le32_to_cpu(pgpt->sizeof_partition_entry), |
|
le32_to_cpu(agpt->sizeof_partition_entry)); |
|
error_found++; |
|
} |
|
if (le32_to_cpu(pgpt->partition_entry_array_crc32) != |
|
le32_to_cpu(agpt->partition_entry_array_crc32)) { |
|
pr_warn("GPT:partition_entry_array_crc32 values don't match: " |
|
"0x%x != 0x%x\n", |
|
le32_to_cpu(pgpt->partition_entry_array_crc32), |
|
le32_to_cpu(agpt->partition_entry_array_crc32)); |
|
error_found++; |
|
} |
|
if (le64_to_cpu(pgpt->alternate_lba) != lastlba) { |
|
pr_warn("GPT:Primary header thinks Alt. header is not at the end of the disk.\n"); |
|
pr_warn("GPT:%lld != %lld\n", |
|
(unsigned long long)le64_to_cpu(pgpt->alternate_lba), |
|
(unsigned long long)lastlba); |
|
error_found++; |
|
} |
|
|
|
if (le64_to_cpu(agpt->my_lba) != lastlba) { |
|
pr_warn("GPT:Alternate GPT header not at the end of the disk.\n"); |
|
pr_warn("GPT:%lld != %lld\n", |
|
(unsigned long long)le64_to_cpu(agpt->my_lba), |
|
(unsigned long long)lastlba); |
|
error_found++; |
|
} |
|
|
|
if (error_found) |
|
pr_warn("GPT: Use GNU Parted to correct GPT errors.\n"); |
|
return; |
|
} |
|
|
|
/** |
|
* find_valid_gpt() - Search disk for valid GPT headers and PTEs |
|
* @state: disk parsed partitions |
|
* @gpt: GPT header ptr, filled on return. |
|
* @ptes: PTEs ptr, filled on return. |
|
* |
|
* Description: Returns 1 if valid, 0 on error. |
|
* If valid, returns pointers to newly allocated GPT header and PTEs. |
|
* Validity depends on PMBR being valid (or being overridden by the |
|
* 'gpt' kernel command line option) and finding either the Primary |
|
* GPT header and PTEs valid, or the Alternate GPT header and PTEs |
|
* valid. If the Primary GPT header is not valid, the Alternate GPT header |
|
* is not checked unless the 'gpt' kernel command line option is passed. |
|
* This protects against devices which misreport their size, and forces |
|
* the user to decide to use the Alternate GPT. |
|
*/ |
|
static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt, |
|
gpt_entry **ptes) |
|
{ |
|
int good_pgpt = 0, good_agpt = 0, good_pmbr = 0; |
|
gpt_header *pgpt = NULL, *agpt = NULL; |
|
gpt_entry *pptes = NULL, *aptes = NULL; |
|
legacy_mbr *legacymbr; |
|
struct gendisk *disk = state->disk; |
|
const struct block_device_operations *fops = disk->fops; |
|
sector_t total_sectors = get_capacity(state->disk); |
|
u64 lastlba; |
|
|
|
if (!ptes) |
|
return 0; |
|
|
|
lastlba = last_lba(state->disk); |
|
if (!force_gpt) { |
|
/* This will be added to the EFI Spec. per Intel after v1.02. */ |
|
legacymbr = kzalloc(sizeof(*legacymbr), GFP_KERNEL); |
|
if (!legacymbr) |
|
goto fail; |
|
|
|
read_lba(state, 0, (u8 *)legacymbr, sizeof(*legacymbr)); |
|
good_pmbr = is_pmbr_valid(legacymbr, total_sectors); |
|
kfree(legacymbr); |
|
|
|
if (!good_pmbr) |
|
goto fail; |
|
|
|
pr_debug("Device has a %s MBR\n", |
|
good_pmbr == GPT_MBR_PROTECTIVE ? |
|
"protective" : "hybrid"); |
|
} |
|
|
|
good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA, |
|
&pgpt, &pptes); |
|
if (good_pgpt) |
|
good_agpt = is_gpt_valid(state, |
|
le64_to_cpu(pgpt->alternate_lba), |
|
&agpt, &aptes); |
|
if (!good_agpt && force_gpt) |
|
good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes); |
|
|
|
if (!good_agpt && force_gpt && fops->alternative_gpt_sector) { |
|
sector_t agpt_sector; |
|
int err; |
|
|
|
err = fops->alternative_gpt_sector(disk, &agpt_sector); |
|
if (!err) |
|
good_agpt = is_gpt_valid(state, agpt_sector, |
|
&agpt, &aptes); |
|
} |
|
|
|
/* The obviously unsuccessful case */ |
|
if (!good_pgpt && !good_agpt) |
|
goto fail; |
|
|
|
compare_gpts(pgpt, agpt, lastlba); |
|
|
|
/* The good cases */ |
|
if (good_pgpt) { |
|
*gpt = pgpt; |
|
*ptes = pptes; |
|
kfree(agpt); |
|
kfree(aptes); |
|
if (!good_agpt) |
|
pr_warn("Alternate GPT is invalid, using primary GPT.\n"); |
|
return 1; |
|
} |
|
else if (good_agpt) { |
|
*gpt = agpt; |
|
*ptes = aptes; |
|
kfree(pgpt); |
|
kfree(pptes); |
|
pr_warn("Primary GPT is invalid, using alternate GPT.\n"); |
|
return 1; |
|
} |
|
|
|
fail: |
|
kfree(pgpt); |
|
kfree(agpt); |
|
kfree(pptes); |
|
kfree(aptes); |
|
*gpt = NULL; |
|
*ptes = NULL; |
|
return 0; |
|
} |
|
|
|
/** |
|
* utf16_le_to_7bit(): Naively converts a UTF-16LE string to 7-bit ASCII characters |
|
* @in: input UTF-16LE string |
|
* @size: size of the input string |
|
* @out: output string ptr, should be capable to store @size+1 characters |
|
* |
|
* Description: Converts @size UTF16-LE symbols from @in string to 7-bit |
|
* ASCII characters and stores them to @out. Adds trailing zero to @out array. |
|
*/ |
|
static void utf16_le_to_7bit(const __le16 *in, unsigned int size, u8 *out) |
|
{ |
|
unsigned int i = 0; |
|
|
|
out[size] = 0; |
|
|
|
while (i < size) { |
|
u8 c = le16_to_cpu(in[i]) & 0xff; |
|
|
|
if (c && !isprint(c)) |
|
c = '!'; |
|
out[i] = c; |
|
i++; |
|
} |
|
} |
|
|
|
/** |
|
* efi_partition - scan for GPT partitions |
|
* @state: disk parsed partitions |
|
* |
|
* Description: called from check.c, if the disk contains GPT |
|
* partitions, sets up partition entries in the kernel. |
|
* |
|
* If the first block on the disk is a legacy MBR, |
|
* it will get handled by msdos_partition(). |
|
* If it's a Protective MBR, we'll handle it here. |
|
* |
|
* We do not create a Linux partition for GPT, but |
|
* only for the actual data partitions. |
|
* Returns: |
|
* -1 if unable to read the partition table |
|
* 0 if this isn't our partition table |
|
* 1 if successful |
|
* |
|
*/ |
|
int efi_partition(struct parsed_partitions *state) |
|
{ |
|
gpt_header *gpt = NULL; |
|
gpt_entry *ptes = NULL; |
|
u32 i; |
|
unsigned ssz = queue_logical_block_size(state->disk->queue) / 512; |
|
|
|
if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) { |
|
kfree(gpt); |
|
kfree(ptes); |
|
return 0; |
|
} |
|
|
|
pr_debug("GUID Partition Table is valid! Yea!\n"); |
|
|
|
for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) { |
|
struct partition_meta_info *info; |
|
unsigned label_max; |
|
u64 start = le64_to_cpu(ptes[i].starting_lba); |
|
u64 size = le64_to_cpu(ptes[i].ending_lba) - |
|
le64_to_cpu(ptes[i].starting_lba) + 1ULL; |
|
|
|
if (!is_pte_valid(&ptes[i], last_lba(state->disk))) |
|
continue; |
|
|
|
put_partition(state, i+1, start * ssz, size * ssz); |
|
|
|
/* If this is a RAID volume, tell md */ |
|
if (!efi_guidcmp(ptes[i].partition_type_guid, PARTITION_LINUX_RAID_GUID)) |
|
state->parts[i + 1].flags = ADDPART_FLAG_RAID; |
|
|
|
info = &state->parts[i + 1].info; |
|
efi_guid_to_str(&ptes[i].unique_partition_guid, info->uuid); |
|
|
|
/* Naively convert UTF16-LE to 7 bits. */ |
|
label_max = min(ARRAY_SIZE(info->volname) - 1, |
|
ARRAY_SIZE(ptes[i].partition_name)); |
|
utf16_le_to_7bit(ptes[i].partition_name, label_max, info->volname); |
|
state->parts[i + 1].has_info = true; |
|
} |
|
kfree(ptes); |
|
kfree(gpt); |
|
strlcat(state->pp_buf, "\n", PAGE_SIZE); |
|
return 1; |
|
}
|
|
|