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The kernel automatically evaluates partition tables of storage devices. The code for evaluating GUID partitions (in fs/partitions/efi.c) contains a bug that causes a kernel oops on certain corrupted GUID partition tables. This bug has security impacts, because it allows, for example, to prepare a storage device that crashes a kernel subsystem upon connecting the device (e.g., a "USB Stick of (Partial) Death"). crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size)); computes a CRC32 checksum over gpt covering (*gpt)->header_size bytes. There is no validation of (*gpt)->header_size before the efi_crc32 call. A corrupted partition table may have large values for (*gpt)->header_size. In this case, the CRC32 computation access memory beyond the memory allocated for gpt, which may cause a kernel heap overflow. Validate value of GUID partition table header size. [akpm@linux-foundation.org: fix layout and indenting] Signed-off-by: Timo Warns <warns@pre-sense.de> Cc: Matt Domsch <Matt_Domsch@dell.com> Cc: Eugene Teo <eugeneteo@kernel.sg> Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
676 lines
21 KiB
C
676 lines
21 KiB
C
/************************************************************
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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 <Matt_Domsch@dell.com>
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* Copyright 2000,2001,2002,2004 Dell Inc.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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*
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* TODO:
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*
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* Changelog:
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* Mon Nov 09 2004 Matt Domsch <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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* - Removed __PRIPTR_PREFIX - not being used
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*
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* Mon Jan 14 2002 Matt Domsch <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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 <Martin.Wilck@Fujitsu-Siemens.com>
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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 <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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 <Matt_Domsch@dell.com>
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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/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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/* 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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* 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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* last_lba(): return number of last logical block of device
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* @bdev: 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 block_device *bdev)
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{
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if (!bdev || !bdev->bd_inode)
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return 0;
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return div_u64(bdev->bd_inode->i_size,
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bdev_logical_block_size(bdev)) - 1ULL;
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}
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static inline int
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pmbr_part_valid(struct partition *part)
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{
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if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
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le32_to_cpu(part->start_sect) == 1UL)
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return 1;
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return 0;
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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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*
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* Description: Returns 1 if PMBR is valid, 0 otherwise.
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* Validity depends on two things:
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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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static int
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is_pmbr_valid(legacy_mbr *mbr)
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{
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int i;
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if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
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return 0;
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for (i = 0; i < 4; i++)
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if (pmbr_part_valid(&mbr->partition_record[i]))
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return 1;
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return 0;
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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
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* @lba
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* @buffer
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* @size_t
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*
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* Description: Reads @count bytes from @state->bdev 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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struct block_device *bdev = state->bdev;
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sector_t n = lba * (bdev_logical_block_size(bdev) / 512);
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if (!buffer || lba > last_lba(bdev))
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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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* alloc_read_gpt_entries(): reads partition entries from disk
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* @state
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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 = 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 = kzalloc(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,
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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
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* @lba is 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->bdev.
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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 = bdev_logical_block_size(state->bdev);
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gpt = kzalloc(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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* is_gpt_valid() - tests one GPT header and PTEs for validity
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* @state
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* @lba is the logical block address of the GPT header to test
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* @gpt is a GPT header ptr, filled on return.
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* @ptes is a 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;
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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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/* 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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/* Check the GUID Partition Table header size */
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if (le32_to_cpu((*gpt)->header_size) >
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bdev_logical_block_size(state->bdev)) {
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pr_debug("GUID Partition Table Header size is wrong: %u > %u\n",
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le32_to_cpu((*gpt)->header_size),
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bdev_logical_block_size(state->bdev));
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goto fail;
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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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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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/* 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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/* 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->bdev);
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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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/* 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 Partitition Entry Size check failed.\n");
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goto fail;
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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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/* Check the GUID Partition Entry Array CRC */
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crc = efi_crc32((const unsigned char *) (*ptes),
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le32_to_cpu((*gpt)->num_partition_entries) *
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le32_to_cpu((*gpt)->sizeof_partition_entry));
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if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) {
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pr_debug("GUID Partitition Entry Array CRC check failed.\n");
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goto fail_ptes;
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}
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/* We're done, all's well */
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return 1;
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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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* is_pte_valid() - tests one PTE for validity
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* @pte is the pte to check
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* @lastlba is 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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* compare_gpts() - Search disk for valid GPT headers and PTEs
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* @pgpt is the primary GPT header
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* @agpt is the alternate GPT header
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* @lastlba is the last LBA number
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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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printk(KERN_WARNING
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"GPT:Primary header LBA != Alt. header alternate_lba\n");
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printk(KERN_WARNING "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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printk(KERN_WARNING
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"GPT:Primary header alternate_lba != Alt. header my_lba\n");
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printk(KERN_WARNING "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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printk(KERN_WARNING "GPT:first_usable_lbas don't match.\n");
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printk(KERN_WARNING "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)) {
|
|
printk(KERN_WARNING "GPT:last_usable_lbas don't match.\n");
|
|
printk(KERN_WARNING "GPT:%lld != %lld\n",
|
|
(unsigned long long)le64_to_cpu(pgpt->last_usable_lba),
|
|
(unsigned long long)le64_to_cpu(agpt->last_usable_lba));
|
|
error_found++;
|
|
}
|
|
if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) {
|
|
printk(KERN_WARNING "GPT:disk_guids don't match.\n");
|
|
error_found++;
|
|
}
|
|
if (le32_to_cpu(pgpt->num_partition_entries) !=
|
|
le32_to_cpu(agpt->num_partition_entries)) {
|
|
printk(KERN_WARNING "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)) {
|
|
printk(KERN_WARNING
|
|
"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)) {
|
|
printk(KERN_WARNING
|
|
"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) {
|
|
printk(KERN_WARNING
|
|
"GPT:Primary header thinks Alt. header is not at the end of the disk.\n");
|
|
printk(KERN_WARNING "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) {
|
|
printk(KERN_WARNING
|
|
"GPT:Alternate GPT header not at the end of the disk.\n");
|
|
printk(KERN_WARNING "GPT:%lld != %lld\n",
|
|
(unsigned long long)le64_to_cpu(agpt->my_lba),
|
|
(unsigned long long)lastlba);
|
|
error_found++;
|
|
}
|
|
|
|
if (error_found)
|
|
printk(KERN_WARNING
|
|
"GPT: Use GNU Parted to correct GPT errors.\n");
|
|
return;
|
|
}
|
|
|
|
/**
|
|
* find_valid_gpt() - Search disk for valid GPT headers and PTEs
|
|
* @state
|
|
* @gpt is a GPT header ptr, filled on return.
|
|
* @ptes is a 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;
|
|
u64 lastlba;
|
|
|
|
if (!ptes)
|
|
return 0;
|
|
|
|
lastlba = last_lba(state->bdev);
|
|
if (!force_gpt) {
|
|
/* This will be added to the EFI Spec. per Intel after v1.02. */
|
|
legacymbr = kzalloc(sizeof (*legacymbr), GFP_KERNEL);
|
|
if (legacymbr) {
|
|
read_lba(state, 0, (u8 *) legacymbr,
|
|
sizeof (*legacymbr));
|
|
good_pmbr = is_pmbr_valid(legacymbr);
|
|
kfree(legacymbr);
|
|
}
|
|
if (!good_pmbr)
|
|
goto fail;
|
|
}
|
|
|
|
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);
|
|
|
|
/* 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) {
|
|
printk(KERN_WARNING
|
|
"Alternate GPT is invalid, "
|
|
"using primary GPT.\n");
|
|
}
|
|
return 1;
|
|
}
|
|
else if (good_agpt) {
|
|
*gpt = agpt;
|
|
*ptes = aptes;
|
|
kfree(pgpt);
|
|
kfree(pptes);
|
|
printk(KERN_WARNING
|
|
"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;
|
|
}
|
|
|
|
/**
|
|
* efi_partition(struct parsed_partitions *state)
|
|
* @state
|
|
*
|
|
* 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 = bdev_logical_block_size(state->bdev) / 512;
|
|
u8 unparsed_guid[37];
|
|
|
|
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_count = 0;
|
|
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->bdev)))
|
|
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;
|
|
/* Instead of doing a manual swap to big endian, reuse the
|
|
* common ASCII hex format as the interim.
|
|
*/
|
|
efi_guid_unparse(&ptes[i].unique_partition_guid, unparsed_guid);
|
|
part_pack_uuid(unparsed_guid, info->uuid);
|
|
|
|
/* Naively convert UTF16-LE to 7 bits. */
|
|
label_max = min(sizeof(info->volname) - 1,
|
|
sizeof(ptes[i].partition_name));
|
|
info->volname[label_max] = 0;
|
|
while (label_count < label_max) {
|
|
u8 c = ptes[i].partition_name[label_count] & 0xff;
|
|
if (c && !isprint(c))
|
|
c = '!';
|
|
info->volname[label_count] = c;
|
|
label_count++;
|
|
}
|
|
state->parts[i + 1].has_info = true;
|
|
}
|
|
kfree(ptes);
|
|
kfree(gpt);
|
|
strlcat(state->pp_buf, "\n", PAGE_SIZE);
|
|
return 1;
|
|
}
|