/usr/share/doc/linux-image-extra-virtual-lts-wily/changelog.gz is in linux-image-extra-virtual-lts-wily 4.2.0.42.34.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/doc/linux-image-extra-virtual-lts-wily/../linux-image-generic-lts-wily/changelog.gz