/usr/lib/ghc-doc/hoogle/libghc-unixutils-doc.txt is in libghc-unixutils-doc 1.54.1-4build4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-unixutils-doc/html/Unixutils.txt