[2/7] ext4: correct validation check of inode table in ext4_valid_block_bitmap
Commit Message
1.Last valid cluster of inode table is EXT4_B2C(sbi, offset +
sbi->s_itb_per_group - 1). We should make sure last valid cluster is <
max_bit, i.e., EXT4_B2C(sbi, offset + sbi->s_itb_per_group - 1) is <
max_bit rather than EXT4_B2C(sbi, offset + sbi->s_itb_per_group) is
< max_bit.
2.Bit search length should be last valid cluster plus 1, i.e.,
EXT4_B2C(sbi, offset + sbi->s_itb_per_group - 1) + 1 rather than
EXT4_B2C(sbi, offset + sbi->s_itb_per_group).
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
---
fs/ext4/balloc.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
@@ -350,13 +350,13 @@ static ext4_fsblk_t ext4_valid_block_bitmap(struct super_block *sb,
blk = ext4_inode_table(sb, desc);
offset = blk - group_first_block;
if (offset < 0 || EXT4_B2C(sbi, offset) >= max_bit ||
- EXT4_B2C(sbi, offset + sbi->s_itb_per_group) >= max_bit)
+ EXT4_B2C(sbi, offset + sbi->s_itb_per_group - 1) >= max_bit)
return blk;
next_zero_bit = ext4_find_next_zero_bit(bh->b_data,
- EXT4_B2C(sbi, offset + sbi->s_itb_per_group),
+ EXT4_B2C(sbi, offset + sbi->s_itb_per_group - 1) + 1,
EXT4_B2C(sbi, offset));
if (next_zero_bit <
- EXT4_B2C(sbi, offset + sbi->s_itb_per_group))
+ EXT4_B2C(sbi, offset + sbi->s_itb_per_group - 1) + 1)
/* bad bitmap for inode tables */
return blk;
return 0;