/var/lib/dpkg/info/base-files.postinst installs /root/.bashrc from /usr/share/base-files/dot.bashrc . So /root/.bashrc is owned by base-files . I found this is already reported to base-files: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=275623 . And moreover there is a message on bash-completion there, which CC you: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=275623#58 .
-- Askar Safin
