Improper Locking

Summary

MariaDB Server versions prior to 10.2.42, 10.3.x prior to 10.3.33, 10.4.x prior to 10.4.23, 10.5.x prior to 10.5.14, 10.6.x prior to 10.6.6, 10.7.x prior to 10.7.2 are vulnerable to Denial of Service. In "extra/mariabackup/ds_compress.cc", when an error occurs (i.e., going to the err label) while executing the method "create_worker_threads", the held lock "thd->ctrl_mutex" is not released correctly, which allows local users to trigger a denial of service due to the deadlock.