util-linux has the following line in its test-suite:
https://github.com/util-linux/util-linux/blob/90b12595bbe3357fdbccf5eec6c3885e53bc614e/tests/functions.sh#L302
Thus, it will override any setting (e.g. log collection) csmock has set. We can use csexec to make sure the environment will be set correctly.