dovecot - Jul 2021 - quota-status fails when size=0 from Postfix

Am 29.07.21 um 02:44 schrieb dovecot at ptld.com:
>> - sending a test mail with SWAKS returns DUNNO
>> ? (swaks is an SMTP test tool)
>>
>> the difference appears to be the "size=0" line that Postfix
>> sends if I use SWAKS.
> 
> Now im guessing, maybe because you are using a testing tool, maybe it is 
> not sending a message body in the email transmission, so postfix is 
> correcting reporting that message has an email body of zero bytes 
> (size=0).
There is a little body reading "This is a test mailing".
> Dovecot must approve this because current maildir size + 0 != 
> over limit. Maybe you are setup correctly and its just the testing tool 
> that creates an edge case you wont experience in the wild.
That may totally be an edge case. But even then

over-quota + 0 = still-over-quota
> Like you said when sending a real email it gets rejected right?
At least from Thunderbird, yes. But SIZE=? does not seem to be a 
mandatory addition to the RCPT-TO line. Perhaps other mail clients do 
not use SIZE either. Just guessting.

Thanks for your thoughts.

?Christoph

> At least from Thunderbird, yes. But SIZE=? does not seem to be a
> mandatory addition to the RCPT-TO line. Perhaps other mail clients do
> not use SIZE either. Just guessting.

http://www.postfix.org/SMTPD_POLICY_README.html
The "size" attribute value specifies the message size that the client 
specified in the MAIL FROM command (zero if none was specified). With 
Postfix 2.2 and later, it specifies the actual message size after the 
client sends the END-OF-MESSAGE.

Okay, it looks like if you are using an old version of postfix then 
postfix does rely on the client telling it the size of the email. But 
with postfix version 2.2 or newer postfix computes the size itself.