tests: add tests for directory entry blocks with checksum errors

Add some regression tests to examine how e2fsck handles directory
entry blocks and htree blocks with (a) malformed directory entries;
(b) incorrect checksums; or (c) obviously garbage entries.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

tests/f_dir_bad_csum/expect.1

@@ -0,0 +1,62 @@
+Pass 1: Checking inodes, blocks, and sizes
+Pass 2: Checking directory structure
+Directory inode 12, block #0, offset 12: directory passes checks but fails checksum.
+Fix? yes
+
+Directory inode 13, block #0, offset 0: directory has no checksum.
+Fix? yes
+
+Directory inode 13, block #0, offset 1012: directory passes checks but fails checksum.
+Fix? yes
+
+Directory inode 14, block #0, offset 0: directory has no checksum.
+Fix? yes
+
+Directory inode 14, block #0, offset 12: directory passes checks but fails checksum.
+Fix? yes
+
+Directory inode 15, block #0, offset 0: directory has no checksum.
+Fix? yes
+
+Directory inode 15, block #0, offset 1000: directory corrupted
+Salvage? yes
+
+Directory inode 16, block #0, offset 0: directory has no checksum.
+Fix? yes
+
+Directory inode 16, block #0, offset 12: directory corrupted
+Salvage? yes
+
+Directory inode 17, block #0, offset 0: directory has no checksum.
+Fix? yes
+
+Directory inode 17, block #0, offset 0: directory corrupted
+Salvage? yes
+
+Missing '.' in directory inode 17.
+Fix? yes
+
+Setting filetype for entry '.' in ??? (17) to 2.
+Missing '..' in directory inode 17.
+Fix? yes
+
+Setting filetype for entry '..' in ??? (17) to 2.
+Entry 'file' in ??? (18) has invalid inode #: 4294967295.
+Clear? yes
+
+Pass 3: Checking directory connectivity
+'..' in /6 (17) is <The NULL inode> (0), should be / (2).
+Fix? yes
+
+Pass 3A: Optimizing directories
+Pass 4: Checking reference counts
+Unattached inode 19
+Connect to /lost+found? yes
+
+Inode 19 ref count is 2, should be 1.  Fix? yes
+
+Pass 5: Checking group summary information
+
+test_filesys: ***** FILE SYSTEM WAS MODIFIED *****
+test_filesys: 19/128 files (5.3% non-contiguous), 1098/2048 blocks
+Exit status is 1

tests/f_dir_bad_csum/expect.2

@@ -0,0 +1,7 @@
+Pass 1: Checking inodes, blocks, and sizes
+Pass 2: Checking directory structure
+Pass 3: Checking directory connectivity
+Pass 4: Checking reference counts
+Pass 5: Checking group summary information
+test_filesys: 19/128 files (5.3% non-contiguous), 1098/2048 blocks
+Exit status is 0

tests/f_dir_bad_csum/name

@@ -0,0 +1 @@
+dir block w/ missing/bad csum, no tail, or dir block corruption (metadata_csum)

tests/f_htree_bad_csum/expect.1

@@ -0,0 +1,28 @@
+Pass 1: Checking inodes, blocks, and sizes
+Pass 2: Checking directory structure
+Problem in HTREE directory inode 12: root node fails checksum.
+Clear HTree index? yes
+
+Problem in HTREE directory inode 18: root node fails checksum.
+Clear HTree index? yes
+
+Directory inode 24, block #0, offset 1020: directory corrupted
+Salvage? yes
+
+Problem in HTREE directory inode 24: root node fails checksum.
+Clear HTree index? yes
+
+Problem in HTREE directory inode 30: root node fails checksum.
+Clear HTree index? yes
+
+Problem in HTREE directory inode 36: root node fails checksum.
+Clear HTree index? yes
+
+Pass 3: Checking directory connectivity
+Pass 3A: Optimizing directories
+Pass 4: Checking reference counts
+Pass 5: Checking group summary information
+
+test_filesys: ***** FILE SYSTEM WAS MODIFIED *****
+test_filesys: 47/128 files (2.1% non-contiguous), 1108/2048 blocks
+Exit status is 1

tests/f_htree_bad_csum/expect.2

@@ -0,0 +1,7 @@
+Pass 1: Checking inodes, blocks, and sizes
+Pass 2: Checking directory structure
+Pass 3: Checking directory connectivity
+Pass 4: Checking reference counts
+Pass 5: Checking group summary information
+test_filesys: 47/128 files (2.1% non-contiguous), 1108/2048 blocks
+Exit status is 0

tests/f_htree_bad_csum/name

@@ -0,0 +1 @@
+htree block w/ missing/bad csum, bad protective dirent, or htree index corruption (metadata_csum)