From 6fd058f7791087648c683eb8572edf3be3c4c23c Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sun, 17 May 2009 15:38:01 -0400 Subject: ext4: Add a comprehensive block validity check to ext4_get_blocks() To catch filesystem bugs or corruption which could lead to the filesystem getting severly damaged, this patch adds a facility for tracking all of the filesystem metadata blocks by contiguous regions in a red-black tree. This allows quick searching of the tree to locate extents which might overlap with filesystem metadata blocks. This facility is also used by the multi-block allocator to assure that it is not allocating blocks out of the system zone, as well as by the routines used when reading indirect blocks and extents information from disk to make sure their contents are valid. Signed-off-by: "Theodore Ts'o" --- fs/ext4/mballoc.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) (limited to 'fs/ext4/mballoc.c') diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 541bd9adffa2..ed8482e22c0e 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2961,15 +2961,10 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, + le32_to_cpu(es->s_first_data_block); len = ac->ac_b_ex.fe_len; - if (in_range(ext4_block_bitmap(sb, gdp), block, len) || - in_range(ext4_inode_bitmap(sb, gdp), block, len) || - in_range(block, ext4_inode_table(sb, gdp), - EXT4_SB(sb)->s_itb_per_group) || - in_range(block + len - 1, ext4_inode_table(sb, gdp), - EXT4_SB(sb)->s_itb_per_group)) { + if (!ext4_data_block_valid(sbi, block, len)) { ext4_error(sb, __func__, - "Allocating block %llu in system zone of %d group\n", - block, ac->ac_b_ex.fe_group); + "Allocating blocks %llu-%llu which overlap " + "fs metadata\n", block, block+len); /* File system mounted not to panic on error * Fix the bitmap and repeat the block allocation * We leak some of the blocks here. -- cgit v1.2.3