Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Description of problem:
dovecot crashes while reading compressed mbox.

Version-Release number of selected component (if applicable):
dovecot-2.3.8-4.el8.x86_64

How reproducible:
Create a mbox file and compress it with xz
Enable compressed mbox feature in dovecot:
https://doc.dovecot.org/configuration_manual/zlib_plugin/

Actual results:
cannot access compressed mailboxes

Expected results:
access compress mailboxes (readonly)

Additional info:
looks like this is fixed upstream:
https://github.com/dovecot/core/commit/9fd62ffaa5ac4a8ec5dee08fdd4bdcc65d582448

Could you provide more information how to reproduce this?

NOTE: In latest dovecot release, they decided to drop XZ support. ATM for writing, in future releases for reading too.
https://github.com/dovecot/core/blob/2.3.14/NEWS

The problem is not related to xz, I only mentioned it as an example.
The bug occures with bzip2 and gz as well.

How to reproduce:
in conf.d/10-mail.conf add
mail_plugins = $mail_plugins zlib

Then activate an mbox archive space:
namespace archive {
  inbox = no
  list = children
  location = mbox:~/Archive:LAYOUT=fs
  prefix = "Archive/"
  separator = /
  subscriptions = yes
  type = private
}

Now create a mbox file in ~/Archive and compress it with gzip.
Daemon dies when accessing the compressed mbox.

NOTE to XZ deprecation:
This is only a XZ problem, other compression libraries are still supported.
https://github.com/dovecot/core/commit/6e5ae5ef0f0f31acd7bde0db53980a708c81eced

After evaluating this issue, there are no plans to address it further or fix it in an upcoming release.  Therefore, it is being closed.  If plans change such that this issue will be fixed in an upcoming release, then the bug can be reopened.