/usr/lib/x86_64-linux-gnu/libmariadb.so is in libmariadb-client-lgpl-dev 2.0.0-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libmariadb.so.2
/usr/lib/x86_64-linux-gnu/libmariadb.so.2