mariadb: improper locking due to the unreleased lock in extra/mariabackup/ds_compress.cc

MariaDB Server before 10.7 is vulnerable to Denial of Service. In extra/mariabackup/dscompress.cc, when an error occurs i.e., going to the err label while executing the method createworkerthreads, the held lock thd-ctrlmutex is not released correctly, which allows local users to trigger a denial ...