/usr/share/lintian/overrides/libion0 is in libion0 3.2.1+dfsg-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | # The libraries comes with the programs
# Nobody else uses the library
libion0: package-name-doesnt-match-sonames
# Override false positive
libion0: hardening-no-fortify-functions
|