mysql-server-8.0.postinst tries to install nonexistent plugin and sets the wrong permissions

[Karoly Negyesi]

First note please that while Bionic https://packages.ubuntu.com/bionic-updates/amd64/mysql-server-5.7/filelist packaged auth_socket.so Focal does not do so. https://packages.ubuntu.com/focal/amd64/mysql-server-8.0/filelist

Yet /var/lib/dpkg/info/mysql-server-8.0.postinst tries to install it and even worse it uses despite it does not exist:

echo "ALTER USER 'root'@'localhost' IDENTIFIED WITH 'auth_socket';" >> "$initfile"

After every MySQL upgrade I need to restart with --skip-grant-tables and undo this because it becomes impossible to log in.

Also

    for d in $mysql_statedir $mysql_filesdir $mysql_keyringdir $mysql_logdir $mysql_rundir
    do
      if [ ! -d "$d" -a ! -L "$d" ]; then mkdir "$d"; fi
      chown -R mysql:mysql $d
      chmod 0700 $d
    done

This makes /var/run/mysqld 0700 which makes it impossible for non-root users to access MySQL over the socket which is inside /var/run/mysqld

[Paride Legovini (paride)]

Hello Karoly and thanks for this bug report. auth_socket.so is now shipped as part of the mysql-server-core-8.0 package:

$ apt-file search auth_socket.so
mysql-server-core-8.0: /usr/lib/mysql/plugin/auth_socket.so

The package is installed as a dependency of mysql-server-8.0. Even if that's not the culprit, looks like you're facing an actual issue. If you believe that's a bug in Ubuntu, could you please provide us with steps to reproduce the problem from a clean Focal system? Thanks!

[Launchpad Janitor (janitor)]

[Expired for mysql-8.0 (Ubuntu) because there has been no activity for 60 days.]