/usr/ is in ruby-buff-config 2.0.0-2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/buff/
/usr/lib/ruby/vendor_ruby/buff/config/
/usr/lib/
/usr/lib/ruby/vendor_ruby/buff/config/errors.rb
/usr/lib/ruby/vendor_ruby/buff/config/json.rb
/usr/lib/ruby/vendor_ruby/buff/config/ruby.rb
/usr/lib/ruby/vendor_ruby/buff/config/version.rb
/usr/lib/ruby/vendor_ruby/buff/config.rb
/usr/lib/ruby/vendor_ruby/buff-config.rb
/usr/share/
/usr/share/doc/
/usr/share/doc/ruby-buff-config/
/usr/share/doc/ruby-buff-config/README.md
/usr/share/doc/ruby-buff-config/changelog.Debian.gz
/usr/share/doc/ruby-buff-config/copyright
/usr/share/lintian/
/usr/share/lintian/overrides/
/usr/share/lintian/overrides/ruby-buff-config
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/all/
/usr/share/rubygems-integration/all/specifications/
/usr/share/rubygems-integration/all/specifications/buff-config-2.0.0.gemspec