/usr/lib/x86_64-linux-gnu/libibumad.so.3 is in libibumad3 17.1-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libibumad.so.3.0.17.1
/usr/lib/x86_64-linux-gnu/libibumad.so.3.0.17.1