=== B1: block size + layout ===
Block Range: 0 - 8191
Block Size: 1024
  Block Range: 1 - 8191

=== B2: file hien tai va kich thuoc (khai niem file slack) ===
r/r 12:	small.bin
-- istat small.bin (inode 12): size vs 1 block = slack --
size: 19
num of links: 1
--
Direct Blocks:
1618 

=== B3: trich toan bo unallocated bang blkls, tim pattern file da xoa ===
-rwxrwxrwx 1 haipanda Administrator 6730752 Oct 18 17:30 unalloc.raw
so lan xuat hien pattern cu trong unallocated: 3936

=== B4: doc truc tiep mot block cu (probe_block=1623) bang blkcat ===
00000000: 4f4c 442d 5345 4352 4554 2d44 4154 412d  OLD-SECRET-DATA-
00000010: 4f4c 442d 5345 4352 4554 2d44 4154 412d  OLD-SECRET-DATA-

=== B5: GHI CHU trung thuc ve slack trong block da tai su dung ===
Block ma file nho chiem lai (first block cua big cu = 1618):
00000000: 4455 204c 4945 5520 4d4f 4920 286e 6761  DU LIEU MOI (nga
00000010: 6e29 0a00 0000 0000 0000 0000 0000 0000  n)..............
00000020: 0000 0000 0000 0000 0000 0000 0000 0000  ................
-> debugfs khi 'write' zero-pad tron block cua file moi, nen phan slack NGAY TRONG
   block vua ghi doc ra la 0 trong lab khong-root nay. Tren o that (OS ghi qua mount)
   OS khong zero duoi block nen slack giu lai du lieu cu. Du vay, du lieu cu VAN con
   o cac block unallocated khac (B3/B4) va do la diem forensic cot loi.
