[Bug 2129196] Re: mysql-server fails to install when an ext4 fs is mounted to /var/lib/mysql

[Launchpad Bug Tracker]

This bug was fixed in the package mysql-8.4 - 8.4.7-0ubuntu2

---------------
mysql-8.4 (8.4.7-0ubuntu2) resolute; urgency=medium

  * d/rules: Skip build tests failing on amd64v3 (LP: #2130339)

mysql-8.4 (8.4.7-0ubuntu1) resolute; urgency=medium

  * Import upstream version 8.4.7 to fix security issues
    - https://www.oracle.com/security-alerts/cpuoct2025.html#AppendixMSQL
    - CVE-2025-53040 CVE-2025-53042 CVE-2025-53044 CVE-2025-53045
      CVE-2025-53053 CVE-2025-53054 CVE-2025-53062 CVE-2025-53069
    Upstream release notes:
    - https://dev.mysql.com/doc/relnotes/mysql/8.4/en/news-8-4-7.html
  * Remove suggests packages no longer in debian and update recommends
  * Update it.po translation file - thanks to Luca Monducci

  [ Zachary Raines ]
  * Update postinst to ignore lost+found directory (LP: #2129196)

 -- Lena Voytek <lena.voytek at canonical.com>  Thu, 30 Oct 2025 10:14:24
-0400

** Changed in: mysql-8.4 (Ubuntu Resolute)
       Status: New => Fix Released

** CVE added: https://cve.org/CVERecord?id=CVE-2025-53040

** CVE added: https://cve.org/CVERecord?id=CVE-2025-53042

** CVE added: https://cve.org/CVERecord?id=CVE-2025-53044

** CVE added: https://cve.org/CVERecord?id=CVE-2025-53045

** CVE added: https://cve.org/CVERecord?id=CVE-2025-53053

** CVE added: https://cve.org/CVERecord?id=CVE-2025-53054

** CVE added: https://cve.org/CVERecord?id=CVE-2025-53062

** CVE added: https://cve.org/CVERecord?id=CVE-2025-53069

-- 
You received this bug notification because you are a member of Ubuntu
Sponsors, which is subscribed to the bug report.
https://bugs.launchpad.net/bugs/2129196

Title:
  mysql-server fails to install when an ext4 fs is mounted to
  /var/lib/mysql

Status in mysql-8.0 package in Ubuntu:
  New
Status in mysql-8.4 package in Ubuntu:
  Fix Released
Status in mysql-8.0 source package in Jammy:
  New
Status in mysql-8.0 source package in Noble:
  New
Status in mysql-8.4 source package in Plucky:
  New
Status in mysql-8.4 source package in Questing:
  New
Status in mysql-8.4 source package in Resolute:
  Fix Released

Bug description:
  [ Impact ]

   * The postinst script for mysql-server checks whether the
  `/var/lib/mysql` directory is empty before setting up the database
  state. When `/var/lib/mysql` is an ext4 filesystem, the `lost+found`
  directory causes this check to fail and the database is not properly
  set up.

   * Mounting a separate volume to hold the mysql state is a common
  pattern, and ext4 is extremely prevalent so this is likely to be a
  common pain point. Although workarounds are straightforward, it makes
  for bad UX.

   * This can be remedied by ignoring the lost+found directory in the
  check.

  [ Test Plan ]

   To ensure bug is fixed:
   * Create an empty ext4 volume and mount it to /var/lib/mysql
   * Install mysql-server
   * Check whether the installation succeeds

   To check that data is preserved:
   * Uninstall and reinstall mysql-server
   * Ensure that the data in /var/lib/mysql is not overwritten

  [ Where problems could occur ]

   * In this case, the only change is to the postinst script, so problems should be related to install.
   * If the check being done were incorrect it could lead to loss of user data.
     - We keep the change to script to a minimum to reduce the risk of this
     - Test plan includes confirming that user data is not overwritten

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/mysql-8.0/+bug/2129196/+subscriptions