January 2023 - dovecot

Question about line length limit in lmtp.
by Kamil Jońca 22 Apr '24

22 Apr '24

I have postfix + dovecot server. Mail for local users are saved by dovecot lmtp. Recently I got some messages from postfix: --8<---------------cut here---------------start------------->8--- 4NQ07L4h4LztXXr: breaking line > 998 bytes with <CR><LF>SPAC --8<---------------cut here---------------end--------------->8--- This is because postfix has configured with default value lmtp_line_length_limit (990). I can turn off this limit (set to 0) but I am curious if dovecot lmtp will accept so lengthty lines? Does dovecot lmtp has any line limits? KJ -- http://stopstopnop.pl/stop_stopnop.pl_o_nas.html

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Bug report: invalid \HasNoChildren in response when asterisk is used in the name
by Merijn Schering 18 Apr '24

18 Apr '24

Hi, I'm using dovecot 2.3.4.1 (f79e8e7e4). I have created a folder called "Test with *". Now when I do a command: A3 LIST "" "%" RETURN (CHILDREN STATUS (MESSAGES UNSEEN)) It responds: * STATUS Test with * ( MESSAGES 0 UNSEEN 0 ) * LIST ( \HasNoChildren \UnMarked ) / Spam But it actually has children! This only happens when I use a * character in the name. I hope you can fix this some day. Thanks! Best regards, Merijn Schering Intermesh https://www.group-office.com https://twitter.com/GroupOffice

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doveadm sync - I/O has stalled
by songliny 09 Apr '24

09 Apr '24

Hi All, We are using dovecot 2.3.19.1 We created a account with more than 1000 mail folders in Maildir format to reproduce the issue. After weeks of testing, we have found a logic that may cause dsync to encounter the error - no activity for 900 seconds.... The function, dsync_ibc_stream_input, is the callback function after some data are ready for be read. This is part of what it does. o_stream_cork(ibc->output); ibc->ibc.io_callback(ibc->ibc.io_context); o_stream_uncork(ibc->output); Normally, ibc->ibc.io_callback(ibc->ibc.io_context) reads some data and then processes it. But when dsync connects over tcps, it uses function implementations in lib-ssl-iostream to send and receive data. And this simplified call stack would result in some data are read when calling o_stream_uncork o_stream_uncork => o_stream_flush => o_stream_ssl_flush_buffer => openssl_iostream_bio_sync => openssl_iostream_bio_input If some data arrive after ibc->ibc.io_callback(ibc->ibc.io_context) and before o_stre am_uncork, o_stream_uncork would read the data and then return. After o_stream_uncork returns, dsync then waits for new data to be read or written. But because the data had been read in o_stream_uncork, and there may be no new data to be read, dsync may then wait until timeout is met. It may happen, but it is hard to reproduce. If you also encounter this situation, you may try to use dsync over tcp connection. It does not read data when calling o_stream_uncork. As a result, it may not stuck. Back to the error itself, Maybe openssl-stream should not read data when doing uncork(flush)? Song-Lin Yang

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2.4 ballpark release date?
by Shawn Heisey 05 Apr '24

05 Apr '24

I'm wondering whether there is a ballpark release date for Dovecot 2.4. I know an exact release date is probably not available, but can it at least be narrowed to a specific quarter? Is it likely in 2023? I have seen on previous messages that an Ubuntu repository for 22.04 (jammy) will appear with the 2.4 release. My mail server in AWS is running Ubuntu 20.04 (focal), which I have avoided upgrading for various reasons, including websites that don't work with PHP 8.1. Now the last remaining hurdle is the fact that there is no dovecot repository for jammy. I would prefer the official Dovecot repo over dovecot packages included with Ubuntu, because it's likely to be a newer release, and built from vanilla project code. At the moment jammy includes dovecot 2.3.16, which is even older than the 2.3.20 that I am running on focal from the official dovecot repo. Again, I know that a precise release date won't be possible. I'm just hoping for something like "soon" or "in about six months." Thanks, Shawn

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[Dovecot] doveadm delete folders ?
by Robert Schetterer 19 Feb '24

19 Feb '24

Hi , is there a feature like doveadm expunge savedbefore ... for imap folder delete ? -- Best Regards MfG Robert Schetterer Germany/Munich/Bavaria

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Recommended changes for delivery from Exim
by jgh＠exim.org 05 Feb '24

05 Feb '24

Hi, Security changes to Exim have invalidated certain suggested configurations in the Dovecot wiki. As I do not have a Dovecot installation to test, I am not going to write any updates there. It would be good if someone would test these suggestions and then make updates as needed. 1) The use of $local_part and $domain in commands run by the "pipe" transport will be disallowed in the upcoming Exim release. These are currently noted as optional, with the "-m" flag to dovecot-lda. They should be replaced with validated (untainted) versions, commonly $local_part_data and $domain_data, developed via one of the several de-taint methods documented for Exim. The same applies to $original_local_part and $original_domain. 2) The use of $sender_address will likewise be disallowed. This and the "-f" flag can be dropped from the dovecot-lda command line, and the specification of a null "message_prefix" option removed. The defaults for a pipe transport will then prefix the message with a suitable Mbox "From " header line, which dovecot-lda is documented to extract the sender from. Both of these suggestions are back-compatible to the current 4.95 release of Exim, and will be required with the 4.96 release. -- Cheers, Jeremy Refs: - https://wiki.dovecot.org/LDA/Exim - https://doc.dovecot.org/configuration_manual/protocols/lda/

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JMAP support?
by Mark Constable 31 Jan '24

31 Jan '24

On Fri Jan 25 2019 Aki wrote: > There is no JMAP support in any dovecot version yet. Two years on so what is the status of JMAP support in Dovecot now?

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replicator: Panic: data stack: Out of memory when allocating 268435496 bytes
by Gerben Wierda 06 Dec '23

06 Dec '23

One step further in my quest to create a replacement mail server. I now have my old mail server (2.3.19.1, macOS + MacPorts) and my new (2.3.20, Alpine Linux, Docker, apk package). When I turn on replication it works, but, after a while I see: Jan 06 00:50:31 replicator: Panic: data stack: Out of memory when allocating 268435496 bytes Jan 06 00:50:32 replicator: Fatal: master: service(replicator): child 133 killed with signal 6 (core dumped) Jan 06 00:50:32 lmtp(pid 195 user sysbh): Warning: replication(sysbh): Sync failure: Jan 06 00:50:32 lmtp(pid 195 user sysbh): Warning: replication(sysbh): Remote sent invalid input: - I've removed synchronous operation for now (found a message on the net suggesting that) but is this known and what does it mean? Gerben Wierda (LinkedIn <https://www.linkedin.com/in/gerbenwierda>) R&A IT Strategy <https://ea.rna.nl/> (main site) Book: Chess and the Art of Enterprise Architecture <https://ea.rna.nl/the-book/> Book: Mastering ArchiMate <https://ea.rna.nl/the-book-edition-iii/>

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bug report: lmtp fails on root-squashed NFS filesystem
by Anne Bennett 09 Oct '23

09 Oct '23

Hi, all. I'm trying to set up Postfix with dovecot LTMP delivery on a host where the user files (/var/spool/mail as well as home directories) are on NFS filesystems, which are exported root-squashed to the mail server. I definitely don't want to give the mail server root permissions on the user files. LMTP delivery fails with this logged message (e.g.): Nov 16 17:51:36 lust dovecot: lmtp(anne)<16830><mkkzEPg1lGG+QQAAs/mAJw>: msgid=<202111162229.1AGMTfAO024765(a)vindemiatrix.encs.concordia.ca>: save failed to INBOX: Read-only mbox I found this posting where someone else had a similar problem and traced it in some detail back in 2019: https://dovecot.org/list/dovecot/2019-February/114611.html but apparently no one answered the fellow. In order to check that this is indeed the same problem, I temporarily changed the INBOX definition to make it write into /var/tmp/ (on a local filesystem), and delivery worked. I then temporarily changed the INBOX definition to make it write into an NFS filesystem with root NOT squashed, and again it worked (after I chmodded the directory to 1777 to allow any user to create a file). I believe that the person who wrote the above posting is correct: at some point, file access is (incorrectly) checked as root instead of as the target user. This is a bit of a showstopper for me. Any plans to address this? I attach the output of "dovecot -n", fwiw, but I don't think that this is a configuration problem... Anne. -- Ms. Anne Bennett, Senior Sysadmin, ENCS, Concordia University, Montreal H3G 1M8 anne(a)encs.concordia.ca +1 514 848-2424 x2285

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Compression: all or nothing?
by Alex King 03 Oct '23

03 Oct '23

Using 2.3.13 (89f716dc2) (debian package), with mdbox storage. I considering adding the zlib plugin. I understand that reading mail can cope with either compressed or uncompressed mailboxes. I'm wondering if I can leave the main storage uncompressed, while having the alternate storage compressed. There does not seem to be a way to configure this, from https://doc.dovecot.org/settings/plugin/zlib-plugin/ it seems compression (on saving emails) is an all-or-nothing option? Can I leave zlib_save unset in my main configuration, and have doveadm use some alternate configuration with zlib_save set? It doesn't look hopeful because I don't see the ability to use a different config at https://wiki.dovecot.org/Tools/Doveadm/Altmove. Perhaps I would need multiple copies of the daemon running? Or is it better just to compress everything? I plan to store older mails (perhaps 3months+) in the alternative storage, and was thinking it would be nice to have those compressed, while I don't need to compress the main store. Any feedback welcome. Thanks, Alex

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