/usr/lib/ is in ruby-yajl 1.2.0-2+b2.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/ruby/
/usr/lib/x86_64-linux-gnu/ruby/vendor_ruby/
/usr/lib/x86_64-linux-gnu/ruby/vendor_ruby/2.1.0/
/usr/lib/x86_64-linux-gnu/ruby/vendor_ruby/2.1.0/yajl/
/usr/lib/x86_64-linux-gnu/ruby/vendor_ruby/2.1.0/yajl/yajl.so
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/yajl.rb
/usr/lib/ruby/vendor_ruby/yajl/
/usr/lib/ruby/vendor_ruby/yajl/http_stream.rb
/usr/lib/ruby/vendor_ruby/yajl/bzip2.rb
/usr/lib/ruby/vendor_ruby/yajl/gzip.rb
/usr/lib/ruby/vendor_ruby/yajl/gzip/
/usr/lib/ruby/vendor_ruby/yajl/gzip/stream_writer.rb
/usr/lib/ruby/vendor_ruby/yajl/gzip/stream_reader.rb
/usr/lib/ruby/vendor_ruby/yajl/deflate/
/usr/lib/ruby/vendor_ruby/yajl/deflate/stream_writer.rb
/usr/lib/ruby/vendor_ruby/yajl/deflate/stream_reader.rb
/usr/lib/ruby/vendor_ruby/yajl/version.rb
/usr/lib/ruby/vendor_ruby/yajl/deflate.rb
/usr/lib/ruby/vendor_ruby/yajl/json_gem/
/usr/lib/ruby/vendor_ruby/yajl/json_gem/encoding.rb
/usr/lib/ruby/vendor_ruby/yajl/json_gem/parsing.rb
/usr/lib/ruby/vendor_ruby/yajl/json_gem.rb
/usr/lib/ruby/vendor_ruby/yajl/bzip2/
/usr/lib/ruby/vendor_ruby/yajl/bzip2/stream_writer.rb
/usr/lib/ruby/vendor_ruby/yajl/bzip2/stream_reader.rb