Currently, BackgroundWorker connected to a database by calling BackgroundWorkerInitializeConnection with username as NULL can be terminated by non-superuser with pg_signal_backend privilege. When the username is NULL the bgworker process runs as superuser (which is expected as per the documentation - https://www.postgresql.org/docs/current/bgworker.html ), but can the non-superuser (with pg_signal_backend) terminate this superuser owned process? We (Mahendrakar and Myself) think that this is a bug and proposing a fix that sets MyProc->roleId to BOOTSTRAP_SUPERUSERID, similar to InitializeSessionUserId, to prevent non-superuser terminating it.
