mail/dovecot: Upgrade to 184.108.40.206, fixing multiple vulnerabilities.
- CVE-2020-10957: lmtp/submission: A client can crash the server by sending a NOOP command with an invalid string parameter. This occurs particularly for a parameter that doesn't start with a double quote. This applies to all SMTP services, including submission-login, which makes it possible to crash the submission service without authentication.
- CVE-2020-10958: lmtp/submission: Sending many invalid or unknown commands can cause the server to access freed memory, which can lead to a server crash. This happens when the server closes the connection with a "421 Too many invalid commands" error. The bad command limit depends on the service (lmtp or submission) and varies between 10 to 20 bad commands.
- CVE-2020-10967: lmtp/submission: Issuing the RCPT command with an address that has the empty quoted string as local-part causes the lmtp service to crash.
Clean up some REINPLACE warnings whilst we're here.