Mount: permission denied (are you root?) while using docker-in-docker workflow with Docker executor


I am referring to to use docker-in-docker workflow with Docker executor. When I execute the pipeline, I am encountering the below issue

2020-05-23T05:48:17.105408575Z .++++
2020-05-23T05:48:17.105956361Z e is 65537 (0x010001)
2020-05-23T05:48:17.143463623Z Signature ok
2020-05-23T05:48:17.143507078Z subject=CN = docker:dind server
2020-05-23T05:48:17.143677083Z Getting CA Private Key
2020-05-23T05:48:17.157238138Z /certs/server/cert.pem: OK
2020-05-23T05:48:17.161977474Z Generating RSA private key, 4096 bit long modulus (2 primes)
2020-05-23T05:48:17.246030617Z ..................++++
2020-05-23T05:48:17.284894101Z .......++++
2020-05-23T05:48:17.284947790Z e is 65537 (0x010001)
2020-05-23T05:48:17.311669237Z Signature ok
2020-05-23T05:48:17.311705543Z subject=CN = docker:dind client
2020-05-23T05:48:17.311712394Z Getting CA Private Key
2020-05-23T05:48:17.337957567Z /certs/client/cert.pem: OK
2020-05-23T05:48:17.346384315Z mount: permission denied (are you root?)
2020-05-23T05:48:17.346794302Z Could not mount /sys/kernel/security.
2020-05-23T05:48:17.346820929Z AppArmor detection and --privileged mode might break.
2020-05-23T05:48:17.349476873Z mount: permission denied (are you root?)

cat /etc/gitlab-runner/config.toml

name = “atreusdind”
url = “
token = “9kuyYJtz-81gBHDazjv4”
executor = “docker”
tls_verify = false
image = “docker:19.03.9”
privileged = true
disable_entrypoint_overwrite = false
oom_kill_disable = false
disable_cache = false
volumes = ["/var/run/docker.sock:/var/run/docker.sock", “/cache”]
shm_size = 0
run_exec = “”

GitLab version

System information
Current User: git
Using RVM: no
Ruby Version: 2.6.6p146
Gem Version: 2.7.10
Bundler Version:1.17.3
Rake Version: 12.3.3
Redis Version: 5.0.9
Git Version: 2.26.2
Sidekiq Version:5.2.7
Go Version: unknown

GitLab information
Version: 13.0.0
Revision: 6743e883eae
Directory: /opt/gitlab/embedded/service/gitlab-rails
DB Adapter: PostgreSQL
DB Version: 11.7
SSH Clone URL:
Using LDAP: no
Using Omniauth: yes
Omniauth Providers:

GitLab Shell
Version: 13.2.0
Repository storage paths:

  • default: /var/opt/gitlab/git-data/repositories
    GitLab Shell path: /opt/gitlab/embedded/service/gitlab-shell
    Git: /opt/gitlab/embedded/bin/git

Any clue regarding the above mount: permission denied (are you root?). Thanks in advance and i look forward to hearing from you.

Best Regards,



Checking in again if someone can pitch in for my earlier post to this forum. Thanks in advance and I look forward to hearing from you.

Best Regards,


Usually you get this error if the docker image you are using has a non root user as default. since your runner is already privileged, check the source (dockerfile) of the build image.

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