Bind mount docker with specific user and permission [closed]

Question

Scenario I want to use Docker in Docker as per this guide

The key point is that you'll need to bind mount the Docker socket from host machine into the Docker socket inside the container in order to use Docker from inside the container.

Issue The Docker socket on the host machine is always bind mounted into Docker container under root:root. When I execute the container as a non-root user, executing Docker commands gives permission denied.

Question How to bind mount a file from host into Docker container with specific user:group and permission?

Answer 1

I think you can workaround that:

set the group permission on the file to ID not exists on the host, and give the group full access:

chown :999 /path/to/file
chmod 775 /path/to/file
chmod g+s /path/to/file

then on your Dockerfile add the group and assign the user to it:

RUN addgroup --gid 999 GROUPNAME 
RUN adduser --disabled-password --gecos "" --force-badname --ingroup 999 USERNAME