I tried to use a docker_image hook on a RHEL7.7 system using podman with the podman-docker package installed [This setup allows for rootless containers]. The hook attempts to modify the file, but gets a "permission denied" error. From looking at the source code, I see that pre-commit is roughly trying to execute:

docker run -u $(id -u):$(id -g)  -v $(pwd):/src:rw,Z --workdir /src -it <ENTRY> <FILE>

The hook does try to run, but results in permission error.

If, however, I remove the -u option from the source code (locally, languages/docker.py, docker_cmd()), then the hook runs fine: