grep bug

kkenn_at_rot13:~ grep -r foo / > /dev/null
grep: /dev/network: Permission denied
grep: /dev/geom.ctl: Permission denied
grep: /dev/devctl: Permission denied
grep: /dev/ata: Permission denied
grep: /dev/console: Permission denied
grep in realloc(): error: allocation failed
^C^C^CAbort (core dumped)

Kris