JSON logging driver - Log file permissions

I am using JSON logging driver. How can I set log file permissions of the log files? It is obvious that I can change them after they are created, but I need them to be set with specific permissions once they are created.

The file permissions are set to 0640 in docker/daemon/logger/loggerutils/rotatefilewriter.go so viable option is to use setfacl:

setfacl -Rdm g:splunk:r /mnt/docker/containers