The ".." entry problem caused by LU-5626 could be handled better by e2fsck. Instead of just clobbering the second entry and replacing it with "..", if the second entry is well-formed it should link that name elsewhere into the directory using ext2fs_link() (or ext2fs_dir_link() from LU-7370 if available) before replacing it with "..". The replacement ".." entry would be best copied from the existing ".." entry, if available, to preserve the FID and other dirdata information.