From: Tao Ma <boyu.mt@xxxxxxxxxx> Now we can use fallocate to create a large file while keep the size to be small. It will cause the e2fsck complain about it. The test script is simple and I have pasted it here. DEVICE=/dev/sdb1 mount -t ext4 $DEVICE /mnt/ext4 for((i=0;i<10;i++))do fallocate -n -o $[$i*8192] -l 4096 /mnt/ext4/a;done umount $DEVICE e2fsck -fn $DEVICE The error message will be like this: e2fsck 1.42.3 (14-May-2012) Pass 1: Checking inodes, blocks, and sizes Inode 12 has zero length extent (invalid logical block 0, physical block 32775) Clear? no Inode 12, i_blocks is 88, should be 0. Fix? no Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information Block bitmap differences: -(8231--8232) -(32770--32778) Fix? no Now actually the end_blk can be any value which is less than u32, so make end_blk be the maximum value of u32. Cc: Theodore Ts'o <tytso@xxxxxxx> Signed-off-by: Tao Ma <boyu.mt@xxxxxxxxxx> --- lib/ext2fs/extent.c | 4 +--- 1 files changed, 1 insertions(+), 3 deletions(-) diff --git a/lib/ext2fs/extent.c b/lib/ext2fs/extent.c index eb096d6..e2815c2 100644 --- a/lib/ext2fs/extent.c +++ b/lib/ext2fs/extent.c @@ -253,9 +253,7 @@ extern errcode_t ext2fs_extent_open2(ext2_filsys fs, ext2_ino_t ino, ext2fs_le16_to_cpu(eh->eh_entries); handle->path[0].max_entries = ext2fs_le16_to_cpu(eh->eh_max); handle->path[0].curr = 0; - handle->path[0].end_blk = - (EXT2_I_SIZE(handle->inode) + fs->blocksize - 1) >> - EXT2_BLOCK_SIZE_BITS(fs->super); + handle->path[0].end_blk = ((((unsigned long long) 1) << 32) - 1); handle->path[0].visit_num = 1; handle->level = 0; handle->magic = EXT2_ET_MAGIC_EXTENT_HANDLE; -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
