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

[Stephan Bosch]

Op 31-1-2018 om 23:16 schreef Stephan Bosch:
> Op 1/31/2018 om 10:44 PM schreef Christian Authmann:
>> Hello,
>> On 31.01.2018 22:35, Stephan Bosch wrote:
>>> 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.
>> yes, 2.3.0 (c8b89eb), archlinux, x64. Sorry for not mentioning it
>> earlier.
> Whoops, yes, problem is obvious.

Fixed: 
https://github.com/dovecot/core/commit/9d606eb5019bc237cf4add562d54e2345b756f50

Regards,

Stephan.