Ubuntu – Unable to clone a git repository inside a docker container (permission denied)

I am trying to build the OpenJ9 VM and install OpenJDK. Due to some constraints, I must use an older version of OpenJ9, so I am following the instructions given over here. I had installed Docker Desktop on my system from it’s binary a while back and have been using it without any issues.

While following the instructions, I am able to set up my build environment. Once I run the container using the command:

docker run -v <host_directory>:/src -it openj9

A docker container starts running with the prompt:

jenkins@5512b38e49f5:/$ 

Following the instructions, I tried to clone the OpenJDK extensions inside the container using:

jenkins@5512b38e49f5:/$ git clone https://github.com/ibmruntimes/openj9-openjdk-jdk8.git 
fatal: could not create work tree dir 'openj9-openjdk-jdk8': Permission denied

I tried to run the docker container with root permissions:

sudo docker run -v <host_directory>:/src -it openj9

However, to this, I get an error:

docker: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?.
See 'docker run --help'.

I noticed that all of my docker commands run successfully without sudo but they all give the above error when I try to run them with sudo

For example:

docker run hello-world

Hello from Docker!
This message shows that your installation appears to be working correctly.

To generate this message, Docker took the following steps:
 1. The Docker client contacted the Docker daemon.
 2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
    (amd64)
 3. The Docker daemon created a new container from that image which runs the
    executable that produces the output you are currently reading.
 4. The Docker daemon streamed that output to the Docker client, which sent it
    to your terminal.

To try something more ambitious, you can run an Ubuntu container with:
 $ docker run -it ubuntu bash

Share images, automate workflows, and more with a free Docker ID:
 https://hub.docker.com/

For more examples and ideas, visit:
 https://docs.docker.com/get-started/

But running with root:

sudo docker run hello-world

docker: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?.
See 'docker run --help'.

I thought that running the docker container with elevated privilege would give me the required permissions I am not able to run Docker with sudo, which is a surprising problem in itself!

I tried to see if the directory which I am cloning into has the required permissions and it seems like I do:

jenkins@976a091d5163:/$ cd src/
jenkins@976a091d5163:/src$ ls -al
total 8
drwxrwxr-x 2 root root 4096 Apr 10 18:30 .
drwxr-xr-x 1 root root 4096 Apr 11 07:55 ..

I am using Linux Mint 21.3 virginia based on Ubuntu 22.04 and Docker Desktop Current version: 4.27.1 (136059).