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>
So that, if a timeout happens and we decide to stop blocking on the
operation, the writer will not block when they try to report the result
of the operation.
This should address Issue #1780 and it's a follow up for PR #1683,
PR #1754 and PR #1772.
Signed-off-by: Filipe Brandenburger <filbranden@google.com>
Starting with systemd 237, in preparation for cgroup v2, delegation is
only now available for scopes, not slices.
Update libcontainer code to detect whether delegation is available on
both and use that information when creating new slices.
Signed-off-by: Filipe Brandenburger <filbranden@google.com>
The channel was introduced in #1683 to work around a race condition.
However, the check for error in StartTransientUnit ignores the error for
an already existing unit, and in that case there will be no notification
from DBus (so waiting on the channel will make it hang.)
Later PR #1754 added a timeout, which worked around the issue, but we
can fix this correctly by only waiting on the channel when there is no
error. Fix the code to do so.
The timeout handling was kept, since there might be other cases where
this situation occurs (https://bugzilla.redhat.com/show_bug.cgi?id=1548358
mentions calling this code from inside a container, it's unclear whether
an existing container was in use or not, so not sure whether this would
have fixed that bug as well.)
Signed-off-by: Filipe Brandenburger <filbranden@google.com>
In some cases, /sys/fs/cgroups is mounted read-only. In rootless
containers we can consider this effectively identical to having cgroups
that we don't have write permission to -- because the user isn't
responsible for the read-only setup and cannot modify it. The rules are
identical to when /sys/fs/cgroups is not writable by the unprivileged
user.
An example of this is the default configuration of Docker, where cgroups
are mounted as read-only as a preventative security measure.
Reported-by: Vladimir Rutsky <rutsky@google.com>
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Currently Manager accepts nil cgroups when calling Apply, but it will panic then trying to call Destroy with the same config.
Signed-off-by: Denys Smirnov <denys@sourced.tech>
This commit ensures we write the expected freezer cgroup state after
every state check, in case the state check does not give the expected
result. This can happen when a new task is created and prevents the
whole cgroup to be FROZEN, leaving the state into FREEZING instead.
This patch prevents the case of an infinite loop to happen.
Fixes https://github.com/opencontainers/runc/issues/1609
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Ed King <eking@pivotal.io>
Signed-off-by: Gabriel Rosenhouse <grosenhouse@pivotal.io>
Signed-off-by: Konstantinos Karampogias <konstantinos.karampogias@swisscom.com>
This fix tries to address the warnings caused by static build
with go 1.9. As systemd needs dlopen/dlclose, the following warnings
will be generated for static build in go 1.9:
```
root@f4b077232050:/go/src/github.com/opencontainers/runc# make static
CGO_ENABLED=1 go build -tags "seccomp cgo static_build" -ldflags "-w -extldflags -static -X main.gitCommit="1c81e2a794c6e26a4c650142ae8893c47f619764" -X main.version=1.0.0-rc4+dev " -o runc .
/tmp/go-link-113476657/000007.o: In function `_cgo_a5acef59ed3f_Cfunc_dlopen':
/tmp/go-build/github.com/opencontainers/runc/vendor/github.com/coreos/pkg/dlopen/_obj/cgo-gcc-prolog:76: warning: Using 'dlopen' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
```
This fix disables systemd when `static_build` flag is on (apply_nosystemd.go
is used instead).
This fix also fixes a small bug in `apply_nosystemd.go` for return value.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
Fixes: #1557
I'm not quite sure about the root cause, looks like
systemd still want them to be uint64.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
go's switch statement doesn't need an explicit break. Remove it where
that is the case and add a comment to indicate the purpose where the
removal would lead to an empty case.
Found with honnef.co/go/tools/cmd/staticcheck
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Updated logrus to use v1 which includes a breaking name change Sirupsen -> sirupsen.
This includes a manual edit of the docker term package to also correct the name there too.
Signed-off-by: Steven Hartland <steven.hartland@multiplay.co.uk>
replace #1492#1494fix#1422
Since https://github.com/opencontainers/runtime-spec/pull/876 the memory
specifications are now `int64`, as that better matches the visible interface where
`-1` is a valid value. Otherwise finding the correct value was difficult as it
was kernel dependent.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
Since syscall is outdated and broken for some architectures,
use x/sys/unix instead.
There are still some dependencies on the syscall package that will
remain in syscall for the forseeable future:
Errno
Signal
SysProcAttr
Additionally:
- os still uses syscall, so it needs to be kept for anything
returning *os.ProcessState, such as process.Wait.
Signed-off-by: Christy Perez <christy@linux.vnet.ibm.com>
The rootless cgroup manager acts as a noop for all set and apply
operations. It is just used for rootless setups. Currently this is far
too simple (we need to add opportunistic cgroup management), but is good
enough as a first-pass at a noop cgroup manager.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Runc needs to copy certain files from the top of the cgroup cpuset hierarchy
into the container's cpuset cgroup directory. Currently, runc determines
which directory is the top of the hierarchy by using the parent dir of
the first entry in /proc/self/mountinfo of type cgroup.
This creates problems when cgroup subsystems are mounted arbitrarily in
different dirs on the host.
Now, we use the most deeply nested mountpoint that contains the
container's cpuset cgroup directory.
Signed-off-by: Konstantinos Karampogias <konstantinos.karampogias@swisscom.com>
Signed-off-by: Will Martin <wmartin@pivotal.io>
Fixes: #1347Fixes: #1083
The root cause of #1083 is because we're joining an
existed cgroup whose kmem accouting is not initialized,
and it has child cgroup or tasks in it.
Fix it by checking if the cgroup is first time created,
and we should enable kmem accouting if the cgroup is
craeted by libcontainer with or without kmem limit
configed. Otherwise we'll get issue like #1347
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
The `bufio.Scanner.Scan` method returns false either by reaching the
end of the input or an error. After Scan returns false, the Err method
will return any error that occurred during scanning, except that if it
was io.EOF, Err will return nil.
We should check the error when Scan return false(out of the for loop).
Signed-off-by: Wang Long <long.wanglong@huawei.com>
In the cases that we got failure on a subsystem's Apply,
we'll get some subsystems' cgroup directories leftover.
On Docker's point of view, start a container failed, use
`docker rm` to remove the container, but some cgroup files
are leftover.
Sometimes we don't want to clean everyting up when something
went wrong, because we need these inter situation
information to debug what's going on, but cgroup directories
are not useful information we want to keep.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
This PR fix issue in this scenario:
```
in terminal 1:
~# cd /sys/fs/cgroup/cpuset
~# mkdir test
~# cd test
~# cat cpuset.cpus
0-3
~# echo 1 > cpuset.cpu_exclusive (make sure you don't have other cgroups under root)
in terminal 2:
~# echo $$ > /sys/fs/cgroup/cpuset/test/tasks
// set resources.cpu.cpus="0-2" in config.json
~# runc run test1
back to terminal 1:
~# cd test1
~# cat cpuset.cpus
0-2
~# echo 1 > cpuset.cpu_exclusive
in terminal 3:
~# echo $$ > /sys/fs/cgroup/test/tasks
// set resources.cpu.cpus="3" in config.json
~# runc run test2
container_linux.go:247: starting container process caused "process_linux.go:258:
applying cgroup configuration for process caused \"failed to write 0-3\\n to
cpuset.cpus: write /sys/fs/cgroup/cpuset/test2/cpuset.cpus: invalid argument\""
```
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
cgroupData.join method using `WriteCgroupProc` to place the pid into
the proc file, it can avoid attach any pid to the cgroup if -1 is
specified as a pid.
so, replace `writeFile` with `WriteCgroupProc` like `cpuset.go`'s
ApplyDir method.
Signed-off-by: Wang Long <long.wanglong@huawei.com>
After #1009, we don't always set `cgroup.Paths`, so
`getCgroupPath()` will return wrong cgroup path because
it'll take current process's cgroup as the parent, which
would be wrong when we try to find the cgroup path in
`runc ps` and `runc kill`.
Fix it by using `m.GetPath()` to get the true cgroup
paths.
Reported-by: Yang Shukui <yangshukui@huawei.com>
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Revert: #935Fixes: #946
I can reproduce #946 on some machines, the problem is on
some machines, it could be very fast that modify time
of `memory.kmem.limit_in_bytes` could be the same as
before it's modified.
And now we'll call `SetKernelMemory` twice on container
creation which cause the second time failure.
Revert this before we find a better solution.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Setting classid of net_cls cgroup failed:
ERRO[0000] process_linux.go:291: setting cgroup config for ready process caused "failed to write 𐀁 to net_cls.classid: write /sys/fs/cgroup/net_cls,net_prio/user.slice/abc/net_cls.classid: invalid argument"
process_linux.go:291: setting cgroup config for ready process caused "failed to write 𐀁 to net_cls.classid: write /sys/fs/cgroup/net_cls,net_prio/user.slice/abc/net_cls.classid: invalid argument"
The spec has classid as a *uint32, the libcontainer configs should match the type.
Signed-off-by: Hushan Jia <hushan.jia@gmail.com>
Added a unit test to verify that 'cpu.rt_runtime_us' and 'cpu.rt_runtime_us'
cgroup values are set when the cgroup is applied to a process.
Signed-off-by: Ben Gray <ben.r.gray@gmail.com>
before trying to move the process into the cgroup.
This is required if runc itself is running in SCHED_RR mode, as it is not
possible to add a process in SCHED_RR mode to a cgroup which hasn't been
assigned any RT bandwidth. And RT bandwidth is not inherited, each new
cgroup starts with 0 b/w.
Signed-off-by: Ben Gray <ben.r.gray@gmail.com>
Prior to this change a cgroup with a `:` character in it's path was not
parsed correctly (as occurs on some instances of systemd cgroups under
some versions of systemd, e.g. 225 with accounting).
This fixes that issue and adds a test.
Signed-off-by: Euan Kemp <euank@coreos.com>
Delegate is only available in systemd >218, applying it for older systemd will
result in an error. Therefore we should check for it when testing systemd
properties.
Signed-off-by: Daniel, Dao Quang Minh <dqminh89@gmail.com>
Kernel memory cannot be set in these circumstances (before kernel 4.6):
1. kernel memory is not initialized, and there are tasks in cgroup
2. kernel memory is not initialized, and use_hierarchy is enabled,
and there are sub-cgroups
While we don't need to cover case 2 because when we set kernel
memory in runC, it's either:
- in Apply phase when we create the container, and in this case,
set kernel memory would definitely be valid;
- or in update operation, and in this case, there would be tasks
in cgroup, we only need to check if kernel memory is initialized
or not.
Even if we want to check use_hierarchy, we need to check sub-cgroups
as well, but for here, we can just leave it aside.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
`libcontainer/cgroups/utils.go` uses an incorrect path to the
documentation for cgroups. This updates the comment to use the correct
URL. Fixes#794.
Signed-off-by: Jim Berlage <james.berlage@gmail.com>
Avoid parsing the whole lines of mountinfo after all mountpoints
of the target subsytems are found, or when the target subsystem
is not enabled.
Signed-off-by: Tatsushi Inagaki <e29253@jp.ibm.com>
No substantial code change.
Note that some style errors reported by `golint` are not fixed due to possible compatibility issues.
Signed-off-by: Akihiro Suda <suda.kyoto@gmail.com>
When swap memory is unsupported, Docker will set
cgroup.Resources.MemorySwap as -1.
Fixes: https://github.com/docker/docker/pull/21937
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Currently, if we start a container with:
`docker run -ti --name foo --memory 300M --memory-swap 500M busybox sh`
Then we want to update it with:
`docker update --memory 600M --memory-swap 800M foo`
It'll get error because we can't set memory to 600M with
the 500M limit of swap memory.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Based on Golang document, %s is for "the uninterpreted bytes of the
string or slice", so %v is more appropriate.
Signed-off-by: Peng Gao <peng.gao.dut@gmail.com>
Make sure we don't error out collecting statistics for cases where
pids.max == "max". In that case, we can use a limit of 0 which means
"unlimited".
In addition, change the name of the stats attribute (Max) to mirror the
name of the resources attribute in the spec (Limit) so that it's
consistent internally.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
This is required because we manage some of the cgroups ourselves.
This recommendation came from talking with systemd devs about
some of the issues that we see when using the systemd cgroups driver.
Signed-off-by: Mrunal Patel <mrunalp@gmail.com>
In order to allow nice usage statistics (in terms of percentages and
other such data), add the value of pids.max to the PidsStats struct
returned from the pids cgroup controller.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
This prior fix to set "-1" explicitly was lost, and it is simpler to use
the same pointer type from the OCI spec to handle nil pointer == -1 ==
unset case.
Also, as a nearly humorous aside, there was a test for MemorySwappiness
that was actually setting Memory, and it was passing because of this
bug (as it was always setting everyone's MemorySwappiness to zero!)
Docker-DCO-1.1-Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com> (github: estesp)
If you don't move the process out of the named cgroup for systemd then
systemd will try to delete all the cgroups that the process is currently
in.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
When in a non-initial user namespace you cannot update the devices
cgroup whitelist (or blacklist). The kernel won't allow it. So
detect that case and don't try.
This is a step to being able to run docker/runc containers inside a user
namespaced container.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
It's handled in `destroy()`, no need to do this in
`Apply()`. I found this because systemd cgroup didn't
do this removal and it works well.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
In order to avoid problems with security regressions going unnoticed,
add some unit tests that should make sure security regressions in cgroup
path safety cause tests to fail in runC.
Signed-off-by: Aleksa Sarai <asarai@suse.com>
Ensure that path safety is maintained, this essentially reapplies
c0cad6aa5e ("cgroups: fs: fix cgroup.Parent path sanitisation"), which
was accidentally removed in 256f3a8ebc ("Add support for CgroupsPath
field").
Signed-off-by: Aleksa Sarai <asarai@suse.com>
GetMounts is very cpu-expensive. I'll change other funcs in this package
to reuse code from GetCgroupMounts later.
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
Add some further (not critical, since Docker does this already)
validation to systemd slice names, to make sure users don't get cryptic
errors.
Signed-off-by: Aleksa Sarai <asarai@suse.com>
Rather than using '/' to denote hierarchy in slice names, systemd uses
'-' in an odd way. This results in runC incorrectly assuming that
certain kernel features are missing (and using inconsistent paths for
the cgroups not supported by systemd), because the "subsystem path" used
is not the one that systemd has created. Fix all of this by properly
expanding slice names.
Signed-off-by: Aleksa Sarai <asarai@suse.com>
Modify the memory cgroup code such that kmem is not managed by Set(), in
order to allow updating of memory constraints for containers by Docker.
This also removes the need to make memory a special case cgroup.
Signed-off-by: Aleksa Sarai <asarai@suse.com>
It is vital to loudly fail when a user attempts to set a cgroup limit
(rather than using the system default). Otherwise the user will assume
they have security they do not actually have. This mirrors the original
Apply() (that would set cgroup configs) semantics.
Signed-off-by: Aleksa Sarai <asarai@suse.com>