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