[Dovecot] Chrooting the Mail processes

[Bert Koelewijn]

Hello!

Could somebody give some feedback on this configuration:

- OpenBSD box with local ssh users.
- /home directory mounted with nosuid,noexec.
- postfix dropping mail in /home/username/mail/INBOX, with the UID/GID 
of the user.
- dovecot:
     valid_chroot_dirs = /home
     default_mail_env = mbox:/home/%u/mail/:INBOX=/home/%u/mail/INBOX

Are there any obvious ways for a local user to help dovecot escape the 
chroot jail?
How can I check that dovecot is REALLY using /home as chroot jail for 
the imap process?

Thanks!

Bert Koelewijn