/usr/lib/ghc-doc/hoogle/libghc-disk-free-space-doc.txt is in libghc-disk-free-space-doc 0.1.0.1-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-disk-free-space-doc/html/disk-free-space.txt