lda: Warning: Failed to parse return-path header: Invalid character in localpart

[Stephan Bosch]

Op 1/31/2018 om 6:17 PM schreef Christian Authmann:
> Hello,
>
> Sometimes, when delivering mails, this warning appears in my syslog:
>
> > lda(...): Warning: Failed to parse return-path header: Invalid
> character in localpart
>
> dovecot-lda still exits with 0 and the mail is inserted into my inbox.
>
>
> Looking at the mails in question, I determined that the error is
> caused by a multiline Return-Path header. Here's a testcase:
>
> --- snip ---
> Return-Path:
>   <nowhere at example.com>
> From: "Nowhere" <nowhere at example.com>
> To: redacted at example.com
> Subject: Testcase for lda warnings
> Date: Wed, 31 Jan 2018 12:00:00 +0000
>
> This is a message body.
> --- snap ---
>
> Copy into a file, with \r\n line endings, then run something like this:
> > cat testcase.txt | /usr/lib/dovecot/dovecot-lda -e -d '<username>'
> with a username recognized by your running dovecot installation.
>
> The header is 'Return-Path:', \r\n, two spaces, '<...>', \r\n
>
> According to rfc2822 folding rules, that should be valid - the
> Return-Path header allows CFWS at that location.
>
>
> The error message originates in lib-lda/mail-deliver.c in
> mail_deliver_get_return_address(), while the invalid character message
> seems to originate from one of several places in lib-lda/mail-deliver.c

This is Dovecot v2.3.0 right?

Regards,

Stephan.