[eriksjolund]

I just tried this out. The new systemd directive OpenFile= opens up the possibility to pass the file descriptor of a file from the host to a container running in a container. (using rootless Podman running rootless Podman)

sudo systemd-run --property User=test --property OpenFile=/etc/secretfile.txt --collect --pipe --wait --quiet podman run --security-opt label=disable --user podman --device /dev/fuse quay.io/podman/stable podman run -q alpine sh -c "cat <&3"