As the baby step, only unit tests are executed.
Failing tests are currently skipped and will be fixed in follow-up PRs.
Fix#2124
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
/proc/cgroups is meaningless for v2 and should be ignored.
https://github.com/torvalds/linux/blob/v5.3/Documentation/admin-guide/cgroup-v2.rst#deprecated-v1-core-features
* Now GetAllSubsystems() parses /sys/fs/cgroup/cgroup.controller, not /proc/cgroups.
The function result also contains "pseudo" controllers: {"devices", "freezer"}.
As it is hard to detect availability of pseudo controllers, pseudo controllers
are always assumed to be available.
* Now IOGroupV2.Name() returns "io", not "blkio"
Fix#2155#2156
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
The `static_build` build tag was introduced in e9944d0f
to remove build warnings related to systemd cgroup driver
dependencies. Since then, those dependencies have changed and
building the systemd cgroup driver no longer imports dlopen.
After this change, runc builds will always include the systemd
cgroup driver.
This fixes#2008.
Signed-off-by: James Peach <jpeach@apache.org>
Implemented `runc ps` for cgroup v2 , using a newly added method `m.GetUnifiedPath()`.
Unlike the v1 implementation that checks `m.GetPaths()["devices"]`, the v2 implementation does not require the device controller to be available.
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
allow to set what subsystems are used by
libcontainer/cgroups/fs.Manager.
subsystemsUnified is used on a system running with cgroups v2 unified
mode.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Transient units (and transient slice units) have been available for quite a
long time and RHEL 7 with systemd v219 (likely the oldest OS we care about at
this point) supports that. A system running a systemd without these features is
likely to break a lot of other stuff that runc/libcontainer care about.
Regarding delegated slices, modern systemd doesn't allow it and
runc/libcontainer run fine on it, so we might as well just stop requesting it
on older versions of systemd which allowed it. (Those versions never really
changed behavior significantly when that option was passed anyways.)
Signed-off-by: Filipe Brandenburger <filbranden@gmail.com>
This dependency is only needed in package "github.com/coreos/go-systemd/util"
and we only use it for IsRunningSystemd(), which is a simple Go function that
just stats a file.
Let's just borrow it here, so we remove the dependency and can remove that
package from vendored build.
This also removes dependencies on dlopen and on trying to find libsystemd.so
or libsystemd-login.so in the system.
Tested that this still builds and works as expected.
Signed-off-by: Filipe Brandenburger <filbranden@gmail.com>
The hugetlb cgroup control files (introduced here in 2012:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=abb8206cb0773)
use "KB" and not "kB"
(https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/mm/hugetlb_cgroup.c?h=v5.0#n349).
The behavior in the kernel has not changed since the introduction, and
the current code using "kB" will therefore fail on devices with small
amounts of ram (see
https://github.com/kubernetes/kubernetes/issues/77169) running a kernel
with config flag CONFIG_HUGETLBFS=y
As seen from the code in "mem_fmt" inside hugetlb_cgroup.c, only "KB",
"MB" and "GB" are used, so the others may be removed as well.
Here is a real world example of the files inside the
"/sys/kernel/mm/hugepages/" directory:
- "hugepages-64kB"
- "hugepages-2048kB"
- "hugepages-32768kB"
- "hugepages-1048576kB"
And the corresponding cgroup files:
- "hugetlb.64KB._____"
- "hugetlb.2MB._____"
- "hugetlb.32MB._____"
- "hugetlb.1GB._____"
Signed-off-by: Odin Ugedal <odin@ugedal.com>
This will permit us to extend the internals of systemd.Manager to include
further information about the system, such as whether cgroupv1, cgroupv2 or
both are in effect.
Furthermore, it allows a future refactor of moving more of UseSystemd() code
into the factory initialization function.
Signed-off-by: Filipe Brandenburger <filbranden@gmail.com>
The detection for scope properties (whether scope units support
DefaultDependencies= or Delegate=) has always been broken, since systemd
refuses to create scopes unless at least one PID is attached to it (and
this has been so since scope units were introduced in systemd v205.)
This can be seen in journal logs whenever a container is started with
libpod:
Feb 11 15:08:07 myhost systemd[1]: libcontainer-12345-systemd-test-default-dependencies.scope: Scope has no PIDs. Refusing.
Feb 11 15:08:07 myhost systemd[1]: libcontainer-12345-systemd-test-default-dependencies.scope: Scope has no PIDs. Refusing.
Since this logic never worked, just assume both attributes are supported
(which is what the code does when detection fails for this reason, since
it's looking for an "unknown attribute" or "read-only attribute" to mark
them as false) and skip the detection altogether.
Signed-off-by: Filipe Brandenburger <filbranden@google.com>
since commit df3fa115f9 it is not
possible to set a kernel memory limit when using the systemd cgroups
backend as we use cgroup.Apply twice.
Skip enabling kernel memory if there are already tasks in the cgroup.
Without this patch, runc fails with:
container_linux.go:344: starting container process caused
"process_linux.go:311: applying cgroup configuration for process
caused \"failed to set memory.kmem.limit_in_bytes, because either
tasks have already joined this cgroup or it has children\""
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
The kernel will sometimes return EINVAL when writing a pid to a
cgroup.procs file. It does so when the task being added still has the
state TASK_NEW.
See: https://elixir.bootlin.com/linux/v4.8/source/kernel/sched/core.c#L8286
Co-authored-by: Danail Branekov <danailster@gmail.com>
Signed-off-by: Tom Godkin <tgodkin@pivotal.io>
Signed-off-by: Danail Branekov <danailster@gmail.com>
When built with nokmem we explicitly are disabling support for kmemcg,
but it is a strict specification requirement that if we cannot fulfil an
aspect of the container configuration that we error out.
Completely ignoring explicitly-requested kmemcg limits with nokmem would
undoubtably lead to problems.
Fixes: 6a2c155968 ("libcontainer: ability to compile without kmem")
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Commit fe898e7862 (PR #1350) enables kernel memory accounting
for all cgroups created by libcontainer -- even if kmem limit is
not configured.
Kernel memory accounting is known to be broken in some kernels,
specifically the ones from RHEL7 (including RHEL 7.5). Those
kernels do not support kernel memory reclaim, and are prone to
oopses. Unconditionally enabling kmem acct on such kernels lead
to bugs, such as
* https://github.com/opencontainers/runc/issues/1725
* https://github.com/kubernetes/kubernetes/issues/61937
* https://github.com/moby/moby/issues/29638
This commit gives a way to compile runc without kernel memory setting
support. To do so, use something like
make BUILDTAGS="seccomp nokmem"
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Cgroup namespace can be configured in `config.json` as other
namespaces. Here is an example:
```
"namespaces": [
{
"type": "pid"
},
{
"type": "network"
},
{
"type": "ipc"
},
{
"type": "uts"
},
{
"type": "mount"
},
{
"type": "cgroup"
}
],
```
Note that if you want to run a container which has shared cgroup ns with
another container, then it's strongly recommended that you set
proper `CgroupsPath` of both containers(the second container's cgroup
path must be the subdirectory of the first one). Or there might be
some unexpected results.
Signed-off-by: Yuanhong Peng <pengyuanhong@huawei.com>
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Currently runc applies PidsLimit restriction by writing directly to
cgroup's pids.max, without notifying systemd. As a consequence, when the
later updates the context of the corresponding scope, pids.max is reset
to the value of systemd's TasksMax property.
This can be easily reproduced this way (I'm using "postfix" here just an
example, any unrelated but existing service will do):
# CTR=`docker run --pids-limit 111 --detach --rm busybox /bin/sleep 8h`
# cat /sys/fs/cgroup/pids/system.slice/docker-${CTR}.scope/pids.max
111
# systemctl disable --now postfix
# systemctl enable --now postfix
# cat /sys/fs/cgroup/pids/system.slice/docker-${CTR}.scope/pids.max
max
This patch adds TasksAccounting=true and TasksMax=PidsLimit to the
properties sent to systemd.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Respect the container's cgroup path when finding the container's
cgroup mount point, which is useful in multi-tenant environments, where
containers have their own unique cgroup mounts
Signed-off-by: Danail Branekov <danailster@gmail.com>
Signed-off-by: Oliver Stenbom <ostenbom@pivotal.io>
Signed-off-by: Giuseppe Capizzi <gcapizzi@pivotal.io>
Fix duplicate entries and missing entries in getCgroupMountsHelper
Add test for testing cgroup mounts on bedrock linux
Stop relying on number of subsystems for cgroups
LGTMs: @crosbymichael @cyphar
Closes#1817
This PR decomposes `libcontainer/configs.Config.Rootless bool` into `RootlessEUID bool` and
`RootlessCgroups bool`, so as to make "runc-in-userns" to be more compatible with "rootful" runc.
`RootlessEUID` denotes that runc is being executed as a non-root user (euid != 0) in
the current user namespace. `RootlessEUID` is almost identical to the former `Rootless`
except cgroups stuff.
`RootlessCgroups` denotes that runc is unlikely to have the full access to cgroups.
`RootlessCgroups` is set to false if runc is executed as the root (euid == 0) in the initial namespace.
Otherwise `RootlessCgroups` is set to true.
(Hint: if `RootlessEUID` is true, `RootlessCgroups` becomes true as well)
When runc is executed as the root (euid == 0) in an user namespace (e.g. by Docker-in-LXD, Podman, Usernetes),
`RootlessEUID` is set to false but `RootlessCgroups` is set to true.
So, "runc-in-userns" behaves almost same as "rootful" runc except that cgroups errors are ignored.
This PR does not have any impact on CLI flags and `state.json`.
Note about CLI:
* Now `runc --rootless=(auto|true|false)` CLI flag is only used for setting `RootlessCgroups`.
* Now `runc spec --rootless` is only required when `RootlessEUID` is set to true.
For runc-in-userns, `runc spec` without `--rootless` should work, when sufficient numbers of
UID/GID are mapped.
Note about `$XDG_RUNTIME_DIR` (e.g. `/run/user/1000`):
* `$XDG_RUNTIME_DIR` is ignored if runc is being executed as the root (euid == 0) in the initial namespace, for backward compatibility.
(`/run/runc` is used)
* If runc is executed as the root (euid == 0) in an user namespace, `$XDG_RUNTIME_DIR` is honored if `$USER != "" && $USER != "root"`.
This allows unprivileged users to allow execute runc as the root in userns, without mounting writable `/run/runc`.
Note about `state.json`:
* `rootless` is set to true when `RootlessEUID == true && RootlessCgroups == true`.
Signed-off-by: Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
Add a mountinfo from a bedrock linux system with 4 strata, and include
it for tests
Signed-off-by: Jay Kamat <jaygkamat@gmail.com>
Signed-off-by: Daniel Dao <dqminh89@gmail.com>
When there are complicated mount setups, there can be multiple mount
points which have the subsystem we are looking for. Instead of
counting the mountpoints, tick off subsystems until we have found them
all.
Without the 'all' flag, ignore duplicate subsystems after the first.
Signed-off-by: Daniel Dao <dqminh89@gmail.com>
Include a rootless argument for isIgnorableError to avoid people
accidentally using isIgnorableError when they shouldn't (we don't ignore
any errors when running as root as that really isn't safe).
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Michael Crosby
Akihiro Suda
Mrunal Patel
Qiang Huang
James Peach
tianye15
Giuseppe Scrivano
Filipe Brandenburger
Erik Sipsma
Odin Ugedal
Filipe Brandenburger
Tom Godkin
JoeWrightss
Aleksa Sarai
Kir Kolyshkin
Yuanhong Peng
Sergio Lopez
Dominik Süß
Danail Branekov
Akihiro Suda
Yan Zhu
Jay Kamat
Daniel Dao