Cannot access native directory in docker created by ADD / chown / chmod in Dockerfile

Question

I am trying to add the ssh private key to docker building from the Dockerfile, it looks wired that I cannot access it even if it has full permission

Docker Version: 1.0.0
Docker host: ubuntu 14.04

Here Dockerfile

FROM ubuntu:latest

ENV HOME /home/larry

RUN useradd larry && echo 'larry:docker' | chpasswd
RUN echo "larry ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers

# arrange ssh key
ADD larry.id_rsa $HOME/.ssh/id_rsa

RUN \
    chmod 700 $HOME/.ssh &&\
    chmod 600 $HOME/.ssh/id_rsa 

RUN chown -R larry:larry $HOME

After I create the image and run in the container and su for the user larry, I got

$ id
uid=1000(larry) gid=1000(larry) groups=1000(larry)
$ ls -al
total 12
drwxr-xr-x 5 larry larry 4096 Jun 21 01:29 .
drwxr-xr-x 5 root  root  4096 Jun 21 01:29 ..
drwx------ 2 larry larry 4096 Jun 21 01:29 .ssh
$ cd .ssh
-su: cd: .ssh: Permission denied   

Maybe I missed some basic concept in docker? Just plugged in from a typical unix user perspective.

I also added this to github https://github.com/dotcloud/docker/issues/1295#issuecomment-46700769

Answer 1

# 6047, chown chmod.

Docker :

FROM ubuntu:latest

ENV HOME /home/larry

RUN useradd larry && echo 'larry:docker' | chpasswd
RUN echo "larry ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers

# arrange ssh key
ADD larry.id_rsa $HOME/.ssh/id_rsa

RUN chown -R larry:larry $HOME
RUN \
    chmod 700 $HOME/.ssh &&\
    chmod 600 $HOME/.ssh/id_rsa