/usr/share/man/man1/rust-gdb.1.gz is in rust-gdb 1.24.1+dfsg1-1~deb9u4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man1/gdb.1.gz
/usr/share/man/man1/gdb.1.gz