/usr/share/texmf/doc/latex/latex-cjk is in latex-cjk-common 4.8.3+git20120914-2ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/texmf/doc/latex/../../../doc/latex-cjk-common
/usr/share/texmf/doc/latex/../../../doc/latex-cjk-common