/usr/src/castle-game-engine-5.2.0/fonts/data/DejaVuSerif.ttf is in castle-game-engine-src 5.2.0-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/src/castle-game-engine-5.2.0/fonts/data/../../../../share/fonts/truetype/dejavu/DejaVuSerif.ttf