Recent (probably MacOS) mail app provoking endless cyrus.index writes on 2.3 server. [WARNING: DKIM validation failed]

[ktm at rice.edu]

On Fri, Oct 23, 2015 at 07:38:56PM -0400, Matt Elson wrote:
> > So the exact text after the OK response doesn't matter, but it MUST
> > be SP followed by at least 1 TEXT-CHAR.
> >
> > This is pretty easy to patch in 2.3.x if you're forced to remain
> > there for reasons.  It is, of course, fixed in later versions.
> >
> > Bron.
> >
> >
> 
> I'm seeing this issue in my environment.. I think.  I'm only *fairly* 
> sure - I see clients that are identifying themselves as 10.11 causing 
> lots of entries showing up in the sync log and a whole lot of index 
> churning on.. usually smaller folders, luckily.  I've been trying to 
> track down a test machine to validate, but resources are quite limited 
> where I am.
> 
> But I'm a bit confused about the current working theory as to what's 
> causing Mail.app to go into its strange loop.
> 
> My Cyrus (RedHat provided 2.3.16-13.el6_6 with a very minor local patch) 
> responds to EXPUNGE with "<tag> OK COMPLETED" as near as I can tell.. 
> which seems spec compliant if I understand the above.
> 
> * OK [CAPABILITY IMAP4 IMAP4rev1 LITERAL+ ID 
> MUPDATE=mupdate://redacted.example.com/ AUTH=GSSAPI AUTH=PLAIN 
> AUTH=LOGIN SASL-IR COMPRESS=DEFLATE] redacted.example.com Cyrus IMAP 
> Murder v2.3.16-Fedora-RPM-2.3.16-13.el6_6 server ready
> A0001 login REDACTED PASSWORD
> A0001 OK [CAPABILITY IMAP4 IMAP4rev1 LITERAL+ ID 
> MUPDATE=mupdate://redacted.example.com/ LOGINDISABLED AUTH=GSSAPI 
> AUTH=PLAIN AUTH=LOGIN COMPRESS=DEFLATE ACL RIGHTS=kxte QUOTA 
> MAILBOX-REFERRALS NAMESPACE UIDPLUS NO_ATOMIC_RENAME UNSELECT CHILDREN 
> MULTIAPPEND BINARY SORT SORT=MODSEQ THREAD=ORDEREDSUBJECT 
> THREAD=REFERENCES ANNOTATEMORE CATENATE CONDSTORE SCAN IDLE LISTEXT 
> LIST-SUBSCRIBED X-NETSCAPE URLAUTH] User logged in
> A0002 SELECT Trash
> * FLAGS (\Answered \Flagged \Draft \Deleted \Seen)
> * OK [PERMANENTFLAGS (\Answered \Flagged \Draft \Deleted \Seen \*)]
> * 4560 EXISTS
> * 0 RECENT
> * OK [UNSEEN 1]
> * OK [UIDVALIDITY 1347582296]
> * OK [UIDNEXT 6437]
> * OK [NOMODSEQ] Sorry, modsequences have not been enabled on this mailbox
> * OK [URLMECH INTERNAL]
> A0002 OK [READ-WRITE] Completed
> A0003 idle
> + idling
> done
> A0003 OK Completed
> A0004 EXPUNGE
> * 4560 EXISTS
> * 0 RECENT
> A0004 OK Completed
> 
> 
> In fact a 2.4.18 install I'm building (I'm using this issue as an excuse 
> to prioritize a long time coming upgrade) seems to respond to expunge in 
> the same way.
> 
> 
> * OK [CAPABILITY IMAP4rev1 LITERAL+ ID ENABLE 
> MUPDATE=mupdate://redacted.example.com/ STARTTLS AUTH=LOGIN AUTH=PLAIN 
> AUTH=DIGEST-MD5 SASL-IR] redacted.example.com Cyrus IMAP Murder 
> v2.4.18-Invoca-RPM-2.4.18-1.el7.centos server ready
> A0001 login redacted redacted
> A0001 OK [CAPABILITY IMAP4rev1 LITERAL+ ID ENABLE ACL RIGHTS=kxte QUOTA 
> MAILBOX-REFERRALS NAMESPACE UIDPLUS NO_ATOMIC_RENAME UNSELECT CHILDREN 
> MULTIAPPEND BINARY CATENATE CONDSTORE SORT SORT=MODSEQ SORT=DISPLAY 
> THREAD=ORDEREDSUBJECT THREAD=REFERENCES ANNOTATEMORE WITHIN SCAN XLIST 
> URLAUTH X-NETSCAPE MUPDATE=mupdate://redacted.example.com/ LOGINDISABLED 
> COMPRESS=DEFLATE IDLE] User logged in 
> SESSIONID=<redacted.example.com-28519-1445641933-1>
> A0002 SELECT Trash
> * 0 EXISTS
> * 0 RECENT
> * FLAGS (\Answered \Flagged \Draft \Deleted \Seen)
> * OK [PERMANENTFLAGS (\Answered \Flagged \Draft \Deleted \Seen \*)] Ok
> * OK [UIDVALIDITY 1445555503] Ok
> * OK [UIDNEXT 1] Ok
> * OK [HIGHESTMODSEQ 1] Ok
> * OK [URLMECH INTERNAL] Ok
> A0002 OK [READ-WRITE] Completed
> A0003 idle
> + idling
> done
> A0003 OK Completed
> A0004 EXPUNGE
> A0004 OK Completed
> 
> (And fastmail's IMAP responds with a OK Completed, and I assume it 
> represents the most up to date Cyrus :P)
> 
> Am I misunderstanding the theoretical issue?  My IMAP-fu is a little 
> rusty these days and I'm a bit bleary eyed so apologies in advance if 
> I'm missing something obvious - I'm just testing by typing the commands 
> in raw since imaptest is panicking on me and I've not had time to sort 
> that out (though my Thunderbird debug log also shows an OK Completed as 
> a repsonse).
> 
> It does seem from one of the trace logs from the Apple discussion that 
> there is a version of Cyrus that responds with just OK, but.. it's not 
> all 2.3.x 's at the very least :P.
> 
> Sorry again if this noise and thanks in advance for any clarification 
> someone can give.
> 
> Matt
> 

Hi Matt,

I just confirmed your result. It looks like Redhat had patched that in
there release. I will try and get some El Capitan telemetry on Monday
and see what it is doing.

Regards,
Ken