lmtp crashes with: Panic: file mail-user.c: line 229 (mail_user_deinit): assertion failed: ((*user)->refcount == 1)

Status changed to 'Confirmed' because the bug affects multiple users.

Hi Andre,

Thank you for your report and that you help us with reports.
Could you please provide steps to reproduce that bug?
I will take care of that from Monday.

Thank you

Unfortunately I don't know how to reproduce this problem. It seems to happen with some specific customer accounts, but I'm unable to reproduce the error by configuring them in Thunderbird. It's possible that it only happens for some specific IMAP client.

What I can say is that I've backported the package from Kinetic, which has Dovecot 2.3.19, and the error is fixed for me.

Hi Andre,
If we can not identify steps to recreate and verify this case, can we count on you and your users to verify the packages as they would be serviced?
If so, we could provide a PPA with the package and once confirmed to work fine, we could prepare an SRU upload to Jammy to then have your verification again.
Do you think that you can help us in that case and provide that?

Yes, absolutely!

Hi Andre,

I've prepared a PPA package for you. Please remember that it's only for testing purposes and not intended for anything else.
https://launchpad.net/~michal-maloszewski99/+archive/ubuntu/jammy-dovecot-ppa-1992848
Here is a link which leads to the PPA and there you have a instruction how to add this PPA to your system.
Thank you in advance for your help.

Hi Michał

Unfortunately the error remains when using the packages from your PPA. It seems that the real fix must have been introduced by some other commit in the 2.3.16-2.3.19 period.

Hi Andre,

Thanks for your feedback. I have checked the PPA and my dsc package separately whether I missed something. Nothing is missing.
I have a question for you.
Could you please send me some logs of what happens when you bump into the issue? It'd be helpful.
In addition, please check if you did perform 'apt update' after you've added PPA to your system.
It would also help if you showed me the apt-get logs.
These are the next steps. I will try to find another fix which might be helpful, but maybe you have an extra idea what else might help here as you did at the beginning in the bug report (another commit/fix).

The log message is the same as the one I posted originally. There is also a backtrace, which I didn't include in the original message.

Oct 21 14:04:05 imap1 dovecot: lmtp(1797565): Panic: file mail-user.c: line 229 (mail_user_deinit): assertion failed: ((*user)->refcount == 1)
Oct 21 14:04:05 imap1 dovecot: lmtp(1797565): Error: Raw backtrace: /usr/lib/dovecot/libdovecot.so.0(backtrace_append+0x46) [0x7f655cc53d76] -> /usr/lib/dovecot/libdovecot.so.0(backtrace_get+0x22) [0x7f655cc53e92] -> /usr/lib/dovecot/libdovecot.so.0(+0x109c6b) [0x7f655cc60c6b] -> /usr/lib/dovecot/libdovecot.so.0(+0x109d07) [0x7f655cc60d07] -> /usr/lib/dovecot/libdovecot.so.0(+0x5cf53) [0x7f655cbb3f53] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0x483c5) [0x7f655cd753c5] -> dovecot/lmtp [10.20.32.185 DATA](lmtp_local_data+0x3e6) [0x564ff3232996] -> dovecot/lmtp [10.20.32.185 DATA](client_default_cmd_data+0x191) [0x564ff32314c1] -> dovecot/lmtp [10.20.32.185 DATA](cmd_data_continue+0x180) [0x564ff3231250] -> /usr/lib/dovecot/libdovecot.so.0(+0x7c656) [0x7f655cbd3656] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_call_io+0x6d) [0x7f655cc76f1d] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run_internal+0x13a) [0x7f655cc7861a] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run+0x54) [0x7f655cc76fc4] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_run+0x40) [0x7f655cc77180] -> /usr/lib/dovecot/libdovecot.so.0(master_service_run+0x17) [0x7f655cbe96d7] -> dovecot/lmtp [10.20.32.185 DATA](main+0x225) [0x564ff322fec5] -> /lib/x86_64-linux-gnu/libc.so.6(+0x29d90) [0x7f655c951d90] -> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x80) [0x7f655c951e40] -> dovecot/lmtp [10.20.32.185 DATA](_start+0x25) [0x564ff322ffc5]

These are the dpkg logs. I have installed the packages manually because due to network policy reasons the Dovecot server cannot access external repositories.

2022-10-21 12:47:32 upgrade dovecot-core:amd64 1:2.3.19.1+dfsg1-2ubuntu2 1:2.3.16+dfsg1-3ubuntu2.2~ppa1
2022-10-21 12:47:32 status half-configured dovecot-core:amd64 1:2.3.19.1+dfsg1-2ubuntu2
2022-10-21 12:47:32 status unpacked dovecot-core:amd64 1:2.3.19.1+dfsg1-2ubuntu2
2022-10-21 12:47:32 status half-installed dovecot-core:amd64 1:2.3.19.1+dfsg1-2ubuntu2
2022-10-21 12:47:32 status triggers-pending man-db:amd64 2.10.2-1
2022-10-21 12:47:32 status unpacked dovecot-core:amd64 1:2.3.16+dfsg1-3ubuntu2.2~ppa1
2022-10-21 12:47:32 upgrade dovecot-imapd:amd64 1:2.3.19.1+dfsg1-2ubuntu2 1:2.3.16+dfsg1-3ubuntu2.2~ppa1
2022-10-21 12:47:32 status half-configured dovecot-imapd:amd64 1:2.3.19.1+dfsg1-2ubuntu2
2022-10-21 12:47:32 status unpacked dovecot-imapd:amd64 1:2.3.19.1+dfsg1-2ubuntu2
2022-10-21 12:47:32 status half-installed dovecot-imapd:amd64 1:2.3.19.1+dfsg1-2ubuntu2
2022-10-21 12:47:32 status triggers-pending ufw:all 0.36.1-4build1
2022-10-21 12:47:32 status unpacked dovecot-imapd:amd64 1:2.3.16+dfsg1-3ubuntu2.2~ppa1
2022-10-21 12:47:32 upgrade dovecot-lmtpd:amd64 1:2.3.19.1+dfsg1-2ubuntu2 1:2.3.16+dfsg1-3ubuntu2.2~ppa1
2022-10-21 12:47:32 status half-configured dovecot-lmtpd:amd64 1:2.3.19.1+dfsg1-2ubuntu2
2022-10-21 12:47:32 status unpacked dovecot-lmtpd:amd64 1:2.3.19.1+dfsg1-2ubuntu2
2022-10-21 12:47:...

I've marked this Fix Released as Kinetic is on 2.3.19 so this is presumably fixed there, and have opened a task for Jammy to track that the bug needs fixing on Jammy.

Thank you for the details. I think there must be another upstream change that we need to cherry-pick then? We'd be happy to pull it into Jammy for you, but we need some help please, starting with identifying the specific fix. Unfortunately we need to rely on you for this please since we don't know how to reproduce the issue.