70 lines
1.6 KiB
C
70 lines
1.6 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* check_desc.c --- Check the group descriptors of an ext2 filesystem
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*
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* Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
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*
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* %Begin-Header%
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* This file may be redistributed under the terms of the GNU Public
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* License.
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* %End-Header%
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*/
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#include <stdio.h>
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#include <string.h>
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#if HAVE_UNISTD_H
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#include <unistd.h>
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#endif
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#include <fcntl.h>
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#include <time.h>
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#if HAVE_SYS_STAT_H
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#include <sys/stat.h>
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#endif
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#if HAVE_SYS_TYPES_H
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#include <sys/types.h>
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#endif
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#include "ext2_fs.h"
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#include "ext2fs.h"
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/*
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* This routine sanity checks the group descriptors
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*/
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errcode_t ext2fs_check_desc(ext2_filsys fs)
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{
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dgrp_t i;
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blk_t block = fs->super->s_first_data_block;
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blk_t next;
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EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
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for (i = 0; i < fs->group_desc_count; i++) {
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next = block + fs->super->s_blocks_per_group;
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/*
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* Check to make sure block bitmap for group is
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* located within the group.
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*/
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if (fs->group_desc[i].bg_block_bitmap < block ||
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fs->group_desc[i].bg_block_bitmap >= next)
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return EXT2_ET_GDESC_BAD_BLOCK_MAP;
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/*
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* Check to make sure inode bitmap for group is
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* located within the group
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*/
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if (fs->group_desc[i].bg_inode_bitmap < block ||
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fs->group_desc[i].bg_inode_bitmap >= next)
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return EXT2_ET_GDESC_BAD_INODE_MAP;
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/*
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* Check to make sure inode table for group is located
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* within the group
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*/
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if (fs->group_desc[i].bg_inode_table < block ||
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((fs->group_desc[i].bg_inode_table +
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fs->inode_blocks_per_group) >= next))
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return EXT2_ET_GDESC_BAD_INODE_TABLE;
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block = next;
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}
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return 0;
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}
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