This is planned to be the final -rc release of runc. While we really
haven't followed the rules for release candidates (with huge features
introduced each release, and with massive gaps between releases) the
hope is that once we've release 1.0.0 we will be much more liberal with
releases in future. Let's see how that pans out. :P


+ Support cgroups in rootless containers. This is a continuation of the
  previous work done, and allows for users that have specialised setups
  (such as having the LXC pam_cg.so module set up) to use cgroups with
  rootless containers. #1540
+ Add support for newuidmap and newgidmap with rootless containers.
  This is a continuation of some previous work, and allows users that
  have /etc/sub{uid,gid} configured to use the shadow-utils setuid
  helpers. Note that this support doesn't restrict users that don't want
  to use setuid binaries at all. #1529
+ runc will now use a chroot when mount namespaces aren't provided in
  the config.json. While chroot does have its (many) downsides, this
  does allow for specialised configurations to work properly. #1702
+ Expose annotations to hooks, so that the hook can have more direct
  information about the container it is being run against. #1687
+ Add "runc exec --additional-gids" support. #1608
+ Allow more signals to be sent with "runc kill" than are defined by
  Go's syscall package. #1706
+ Emit an error if users try to use MS_PRIVATE with --no-pivot, as that
  is simply not safe. #1606
+ Add support for "unbindable" and "runbindable" as rootfs propagation.
+ Implement intelrdt support in runc. #1279 #1590
+ Add support for lazy migration with CRIU. This includes the addition
  of "runc checkpoint httpd" which acts as a remote pagefault request
  server. #1541
+ Add MIPS support. #1475


* Delay seccomp application as late as possible, to reduce the syscall
  footprint of runc on profiles. #1569
* Fix --read-only containers with user namespaces, which would
  previously fail under Docker because of privilege problems when trying
  to do the read-only remount. #1572
* Switch away from stateDirFd entirely. This is an improvement over the
  protections we added for CVE-2016-9962, and protects against many
  other possible container escape bugs. #1570
* Handle races between "runc start" and "runc delete" over the exec FIFO
  correctly, and avoid blocking "runc start" indefinitely. #1698
* Correctly generate seccomp profiles that place requirements on syscall
  arguments, as well as multi-argument restrictions. #1616 #1424
* Prospective patch for remounting of old-root during pivot_root. This
  is intended to solve one of the many "mount leak" bugs that have been
  popping up recently -- caused by lots of container churn and host
  mounts being pinned during container setup. #1500
* Fix "runc exec" on big-endian architectures. #1727
* Correct systemd slice expansion to work with cAdvisor. #1722
* Fix races against systemd cgroup scope creation. #1683
* Do not wait for signalled processes if libcontainer is running in a
  process that is a subreaper. #1678
* Remove dependency on libapparmor entirely, and just use
  /proc/$pid/attr directly. #1675
* Improvements to our integration tests. #1661 #1629 #1528
* Handle systemd's quirky CPUQuotaPerSecUSec handling in
  fractions-of-a-percent edge-cases. #1651
* Remove docker/docker import in runc by moving the package to runc.
* Switch from docker's pkg/symlink to cyphar/filepath-securejoin. #1622
* Enable integration and unit tests on arm64. #1642 #1640
* Add /proc/scsi to masked paths (mirror of Docker's CVE-2017-16539).
* Add several tests for specconv. #1626 #1619
* Add more extensive tests for terminal handling. #1357
* Always write freezer state during retry-loop, to avoid an indefinite
  hang when new tasks are spawned in the container. #1610
* Create cwd when it doesn't exist in the container. #1604
* Set initial console size based on process spec, to avoid SIGWINCH
  races where initial console size is completely wrong. #1275
* Small fixes for static builds. #1579 #1577
* Use epoll for PTY IO, to avoid issues with systemd's SAK protections.
* Update state.json after a "runc update". #1558
* Switch to umoci's release scripts, to use a more "standardised" and
  distribution-friendly release scheme. Several makefile-fixes included
  as well. #1554 #1542 #1555
* Reap "runc:[1:CHILD]" to avoid intermediate zombies building up. #1506
* Use CRIU's RPC to check the version. #1535
* Always save own namespace paths rather than the path given during
  start-up, to avoid issues where the path disappears afterwards. #1477
* Fix that we incorrectly set the owners of devices. This is still (subtly)
  broken in user namespaces, but will be fixed in a future version. #1743

* Lots of other miscellaneous fixes and cleanups, many of which were
  written by first-time contributors. Thanks for contributing, and
  welcome to the project! #1729 #1724 #1695 #1685 #1703 #1699 #1682
  #1665 #1667 #1669 #1654 #1664 #1660 #1645 #1640 #1621 #1607 #1206
  #1615 #1614 #1453 #1613 #1600 #1599 #1598 #1597 #1593 #1586 #1588
  #1587 #1589 #1575 #1578 #1573 #1561 #1560 #1559 #1556 #1551 #1553
  #1548 #1544 #1545 #1537

- Andrej Vagin stepped down as a maintainer. Thanks for all of your hard
 work Andrej, and have fun working on your other projects! #1543

Thanks to all of the contributors that made this release possible:

 * Adrian Reber <areber@redhat.com>
 * Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
 * Aleksa Sarai <asarai@suse.de>
 * Alex Fang <littlelightlittlefire@gmail.com>
 * Allen Sun <allensun.shl@alibaba-inc.com>
 * Andrei Vagin <avagin@openvz.org>
 * Antonio Murdaca <runcom@redhat.com>
 * Bin Lu <bin.lu@arm.com>
 * Danail Branekov <danail.branekov@sap.com>
 * Daniel, Dao Quang Minh <dqminh89@gmail.com>
 * Ed King <eking@pivotal.io>
 * Euan Kemp <euan.kemp@coreos.com>
 * Giuseppe Scrivano <gscrivan@redhat.com>
 * Jianyong Wu <jianyong.wu@arm.com>
 * Kenfe-Mickael Laventure <mickael.laventure@gmail.com>
 * Konstantinos Karampogias <konstantinos.karampogias@swisscom.com>
 * leitwolf7 <leitwolf@wolke7.net>
 * Lorenzo Fontana <lo@linux.com>
 * Ma Shimiao <mashimiao.fnst@cn.fujitsu.com>
 * Matthew Heon <mheon@redhat.com>
 * Michael Crosby <crosbymichael@gmail.com>
 * Mrunal Patel <mrunal@me.com>
 * Nikolas Sepos <nikolas.sepos@gmail.com>
 * Peter Morjan <peter.morjan@de.ibm.com>
 * Petros Angelatos <petrosagg@gmail.com>
 * Qiang Huang <h.huangqiang@huawei.com>
 * ravisantoshgudimetla <ravisantoshgudimetla@gmail.com>
 * s7v7nislands <s7v7nislands@gmail.com>
 * Sebastien Boeuf <sebastien.boeuf@intel.com>
 * Seth Jennings <sjenning@redhat.com>
 * Steven Hartland <steven.hartland@multiplay.co.uk>
 * Sumit Sanghrajka <sumit.sanghrajka@gmail.com>
 * Taeung Song <treeze.taeung@gmail.com>
 * Thomas Hipp <thipp@suse.de>
 * Tobias Klauser <tklauser@distanz.ch>
 * Tom Godkin <tgodkin@pivotal.io>
 * Tycho Andersen <tycho@docker.com>
 * Valentin Kulesh <valentin.kulesh@virtuozzo.com>
 * vikaschoudhary16 <choudharyvikas16@gmail.com>
 * Vincent Demeester <vincent@sbr.pm>
 * Vladimir Stefanovic <vladimir.stefanovic@imgtec.com>
 * vsoch <vsochat@stanford.edu>
 * Will Martin <wmartin@pivotal.io>
 * W. Trevor King <wking@tremily.us>
 * Xiaochen Shen <xiaochen.shen@intel.com>
 * ynirk <julien.lavesque@gmail.com>
 * Yong Tang <yong.tang.github@outlook.com>
 * Yuanhong Peng <pengyuanhong@huawei.com>
 * yupeng <yu.peng36@zte.com.cn>

Signed-off-by: Aleksa Sarai <asarai@suse.de>
VERSION: bump to v1.0.0-rc5

This is planned to be the last -rc release before 1.0.0.

Signed-off-by: Aleksa Sarai <asarai@suse.de>
1 file changed
tree: d9e0519d5c77a4c51a05461e9aba5bb1cf145707
  1. contrib/
  2. libcontainer/
  3. man/
  4. script/
  5. tests/
  6. vendor/
  7. .gitignore
  8. .pullapprove.yml
  9. .travis.yml
  10. checkpoint.go
  12. create.go
  13. delete.go
  14. Dockerfile
  15. events.go
  16. exec.go
  17. init.go
  18. kill.go
  20. list.go
  21. main.go
  24. Makefile
  25. NOTICE
  26. notify_socket.go
  27. pause.go
  29. ps.go
  30. README.md
  31. restore.go
  32. rlimit_linux.go
  33. run.go
  34. signalmap.go
  35. signalmap_mipsx.go
  36. signals.go
  37. spec.go
  38. start.go
  39. state.go
  40. tty.go
  41. update.go
  42. utils.go
  43. utils_linux.go
  44. vendor.conf


Build Status Go Report Card GoDoc


runc is a CLI tool for spawning and running containers according to the OCI specification.


runc depends on and tracks the runtime-spec repository. We will try to make sure that runc and the OCI specification major versions stay in lockstep. This means that runc 1.0.0 should implement the 1.0 version of the specification.

You can find official releases of runc on the release page.


If you wish to report a security issue, please disclose the issue responsibly to security@opencontainers.org.


runc currently supports the Linux platform with various architecture support. It must be built with Go version 1.6 or higher in order for some features to function properly.

In order to enable seccomp support you will need to install libseccomp on your platform.

e.g. libseccomp-devel for CentOS, or libseccomp-dev for Ubuntu

Otherwise, if you do not want to build runc with seccomp support you can add BUILDTAGS="" when running make.

# create a 'github.com/opencontainers' in your GOPATH/src
cd github.com/opencontainers
git clone https://github.com/opencontainers/runc
cd runc

sudo make install

You can also use go get to install to your GOPATH, assuming that you have a github.com parent folder already created under src:

go get github.com/opencontainers/runc
cd $GOPATH/src/github.com/opencontainers/runc
sudo make install

runc will be installed to /usr/local/sbin/runc on your system.

Build Tags

runc supports optional build tags for compiling support of various features. To add build tags to the make option the BUILDTAGS variable must be set.

make BUILDTAGS='seccomp apparmor'
Build TagFeatureDependency
seccompSyscall filteringlibseccomp
selinuxselinux process and mount labeling
apparmorapparmor profile support
ambientambient capability supportkernel 4.3

Running the test suite

runc currently supports running its test suite via Docker. To run the suite just type make test.

make test

There are additional make targets for running the tests outside of a container but this is not recommended as the tests are written with the expectation that they can write and remove anywhere.

You can run a specific test case by setting the TESTFLAGS variable.

# make test TESTFLAGS="-run=SomeTestFunction"

Dependencies Management

runc uses vndr for dependencies management. Please refer to vndr for how to add or update new dependencies.

Using runc

Creating an OCI Bundle

In order to use runc you must have your container in the format of an OCI bundle. If you have Docker installed you can use its export method to acquire a root filesystem from an existing Docker container.

# create the top most bundle directory
mkdir /mycontainer
cd /mycontainer

# create the rootfs directory
mkdir rootfs

# export busybox via Docker into the rootfs directory
docker export $(docker create busybox) | tar -C rootfs -xvf -

After a root filesystem is populated you just generate a spec in the format of a config.json file inside your bundle. runc provides a spec command to generate a base template spec that you are then able to edit. To find features and documentation for fields in the spec please refer to the specs repository.

runc spec

Running Containers

Assuming you have an OCI bundle from the previous step you can execute the container in two different ways.

The first way is to use the convenience command run that will handle creating, starting, and deleting the container after it exits.

# run as root
cd /mycontainer
runc run mycontainerid

If you used the unmodified runc spec template this should give you a sh session inside the container.

The second way to start a container is using the specs lifecycle operations. This gives you more power over how the container is created and managed while it is running. This will also launch the container in the background so you will have to edit the config.json to remove the terminal setting for the simple examples here. Your process field in the config.json should look like this below with "terminal": false and "args": ["sleep", "5"].

        "process": {
                "terminal": false,
                "user": {
                        "uid": 0,
                        "gid": 0
                "args": [
                        "sleep", "5"
                "env": [
                "cwd": "/",
                "capabilities": {
                        "bounding": [
                        "effective": [
                        "inheritable": [
                        "permitted": [
                        "ambient": [
                "rlimits": [
                                "type": "RLIMIT_NOFILE",
                                "hard": 1024,
                                "soft": 1024
                "noNewPrivileges": true

Now we can go through the lifecycle operations in your shell.

# run as root
cd /mycontainer
runc create mycontainerid

# view the container is created and in the "created" state
runc list

# start the process inside the container
runc start mycontainerid

# after 5 seconds view that the container has exited and is now in the stopped state
runc list

# now delete the container
runc delete mycontainerid

This adds more complexity but allows higher level systems to manage runc and provides points in the containers creation to setup various settings after the container has created and/or before it is deleted. This is commonly used to setup the container‘s network stack after create but before start where the user’s defined process will be running.

Rootless containers

runc has the ability to run containers without root privileges. This is called rootless. You need to pass some parameters to runc in order to run rootless containers. See below and compare with the previous version. Run the following commands as an ordinary user:

# Same as the first example
mkdir ~/mycontainer
cd ~/mycontainer
mkdir rootfs
docker export $(docker create busybox) | tar -C rootfs -xvf -

# The --rootless parameter instructs runc spec to generate a configuration for a rootless container, which will allow you to run the container as a non-root user.
runc spec --rootless

# The --root parameter tells runc where to store the container state. It must be writable by the user.
runc --root /tmp/runc run mycontainerid


runc can be used with process supervisors and init systems to ensure that containers are restarted when they exit. An example systemd unit file looks something like this.

Description=Start My Container

ExecStart=/usr/local/sbin/runc run -d --pid-file /run/mycontainerid.pid mycontainerid
ExecStopPost=/usr/local/sbin/runc delete mycontainerid