/usr/src/linux-headers-3.13.0-67-generic/kernel/sched is in linux-headers-3.13.0-67-generic 3.13.0-67.110.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/src/linux-headers-3.13.0-67-generic/kernel/../../linux-headers-3.13.0-67/kernel/sched