/usr/lib/ruby/ is in ruby-sprockets 2.12.3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/sprockets.rb
/usr/lib/ruby/vendor_ruby/rake/
/usr/lib/ruby/vendor_ruby/rake/sprocketstask.rb
/usr/lib/ruby/vendor_ruby/sprockets/
/usr/lib/ruby/vendor_ruby/sprockets/server.rb
/usr/lib/ruby/vendor_ruby/sprockets/jst_processor.rb
/usr/lib/ruby/vendor_ruby/sprockets/caching.rb
/usr/lib/ruby/vendor_ruby/sprockets/asset_attributes.rb
/usr/lib/ruby/vendor_ruby/sprockets/safety_colons.rb
/usr/lib/ruby/vendor_ruby/sprockets/processing.rb
/usr/lib/ruby/vendor_ruby/sprockets/compressing.rb
/usr/lib/ruby/vendor_ruby/sprockets/bundled_asset.rb
/usr/lib/ruby/vendor_ruby/sprockets/processed_asset.rb
/usr/lib/ruby/vendor_ruby/sprockets/processor.rb
/usr/lib/ruby/vendor_ruby/sprockets/index.rb
/usr/lib/ruby/vendor_ruby/sprockets/base.rb
/usr/lib/ruby/vendor_ruby/sprockets/closure_compressor.rb
/usr/lib/ruby/vendor_ruby/sprockets/utils.rb
/usr/lib/ruby/vendor_ruby/sprockets/directive_processor.rb
/usr/lib/ruby/vendor_ruby/sprockets/cache/
/usr/lib/ruby/vendor_ruby/sprockets/cache/file_store.rb
/usr/lib/ruby/vendor_ruby/sprockets/mime.rb
/usr/lib/ruby/vendor_ruby/sprockets/engines.rb
/usr/lib/ruby/vendor_ruby/sprockets/asset.rb
/usr/lib/ruby/vendor_ruby/sprockets/sass_compressor.rb
/usr/lib/ruby/vendor_ruby/sprockets/sass_importer.rb
/usr/lib/ruby/vendor_ruby/sprockets/manifest.rb
/usr/lib/ruby/vendor_ruby/sprockets/uglifier_compressor.rb
/usr/lib/ruby/vendor_ruby/sprockets/static_asset.rb
/usr/lib/ruby/vendor_ruby/sprockets/errors.rb
/usr/lib/ruby/vendor_ruby/sprockets/yui_compressor.rb
/usr/lib/ruby/vendor_ruby/sprockets/sass_functions.rb
/usr/lib/ruby/vendor_ruby/sprockets/context.rb
/usr/lib/ruby/vendor_ruby/sprockets/scss_template.rb
/usr/lib/ruby/vendor_ruby/sprockets/charset_normalizer.rb
/usr/lib/ruby/vendor_ruby/sprockets/sass_cache_store.rb
/usr/lib/ruby/vendor_ruby/sprockets/paths.rb
/usr/lib/ruby/vendor_ruby/sprockets/ejs_template.rb
/usr/lib/ruby/vendor_ruby/sprockets/eco_template.rb
/usr/lib/ruby/vendor_ruby/sprockets/version.rb
/usr/lib/ruby/vendor_ruby/sprockets/environment.rb
/usr/lib/ruby/vendor_ruby/sprockets/sass_template.rb