Public bug reported: Hi,
Running Ubuntu xenial with current 4.4.0-22-generic kernel and lxd 2.0.2-0ubuntu1~16.04.1, running Ubuntu's patched docker.io package within an unprivileged container (`lxc launch -p default -p docker ubuntu:xenial docker-test`) works, but fails once configuring the container with `lxc config set docker-test security.privileged true`: root@docker-test:~# docker run --rm -it debian:jessie bash docker: Error response from daemon: Cannot start container 07f5ddd392059c60aa12dd2f7292e54e01b153f2e203180f963989257fec9202: [10] System error: write /sys/fs/cgroup/devices/docker/07f5ddd392059c60aa12dd2f7292e54e01b153f2e203180f963989257fec9202/devices.allow: operation not permitted. Upgrading to yakkety's docker.io=1.11.2-0ubuntu4 gives a slightly better error: docker: Error response from daemon: rpc error: code = 2 desc = "oci runtime error: failed to write c 10:200 rwm to devices.allow: write /sys/fs/cgroup/devices/docker/f05ecde20639572f27ac1ecf582b034d313b7d6573bddc2b57bd49ba1326e36d/devices.allow: operation not permitted". Where: lrwxrwxrwx 1 root root 0 Jun 16 18:28 /sys/dev/char/10:200 -> ../../devices/virtual/misc/tun It looks like containerd/runc per default wants to allow access to /dev/net/tun for containers: https://github.com/docker/docker/blob/master/vendor/src/github.com/opencontainers/runc/libcontainer/configs/device_defaults.go#L101 Adding the tuntap device to the docker profile (and restarting the container): lxc profile device add docker tuntap unix-char path=/dev/net/tun allows the device within the devices cgroup hierarchy: root@docker-test:~# cat /sys/fs/cgroup/devices/devices.list c *:* m b *:* m c 5:0 rwm c 5:1 rwm c 1:5 rwm c 1:7 rwm c 1:3 rwm c 1:8 rwm c 1:9 rwm c 5:2 rwm c 136:* rwm c 10:229 rwm c 10:200 rwm and fixes docker run: root@docker-test:~# docker run --rm -it debian:jessie bash root@7ecba0a17fdd:/# --- On the lxd host: $ lsb_release -rd Description: Ubuntu 16.04 LTS Release: 16.04 $ apt-cache policy lxd lxd: Installed: 2.0.2-0ubuntu1~16.04.1 Candidate: 2.0.2-0ubuntu1~16.04.1 Version table: *** 2.0.2-0ubuntu1~16.04.1 500 500 http://apt/ubuntu xenial-security/main amd64 Packages 500 http://apt/ubuntu xenial-updates/main amd64 Packages 100 /var/lib/dpkg/status 2.0.0-0ubuntu4 500 500 http://apt/ubuntu xenial/main amd64 Packages ** Affects: lxd (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1593301 Title: docker in security.privileged=true containers cannot start containers: write /sys/fs/cgroup/devices/docker/.../devices.allow: operation not permitted To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lxd/+bug/1593301/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs