gofumpt (mvdan.cc/gofumpt) is a fork of gofmt with stricter rules.
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git ls-files \*.go | grep -v ^vendor/ | xargs gofumpt -s -w
Looking at the diff, all these changes make sense.
Also, replace gofmt with gofumpt in golangci.yml.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
This is somewhat radical approach to deal with kernel memory.
Per-cgroup kernel memory limiting was always problematic. A few
examples:
- older kernels had bugs and were even oopsing sometimes (best example
is RHEL7 kernel);
- kernel is unable to reclaim the kernel memory so once the limit is
hit a cgroup is toasted;
- some kernel memory allocations don't allow failing.
In addition to that,
- users don't have a clue about how to set kernel memory limits
(as the concept is much more complicated than e.g. [user] memory);
- different kernels might have different kernel memory usage,
which is sort of unexpected;
- cgroup v2 do not have a [dedicated] kmem limit knob, and thus
runc silently ignores kernel memory limits for v2;
- kernel v5.4 made cgroup v1 kmem.limit obsoleted (see
https://github.com/torvalds/linux/commit/0158115f702b).
In view of all this, and as the runtime-spec lists memory.kernel
and memory.kernelTCP as OPTIONAL, let's ignore kernel memory
limits (for cgroup v1, same as we're already doing for v2).
This should result in less bugs and better user experience.
The only bad side effect from it might be that stat can show kernel
memory usage as 0 (since the accounting is not enabled).
[v2: add a warning in specconv that limits are ignored]
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
c.Parent is only used by systemd cgroup drivers, and both v1 and v2
drivers do have code to set the default if it is empty, so setting
it here is redundant.
In addition, in case of cgroup v2 rootless container setting it here
is harmful as the default should be user.slice not system.slice.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Move the Device-related types to libcontainer/devices, so that
the package can be used in isolation. Aliases have been created
in libcontainer/configs for backward compatibility.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Runc has a set of default devices that it includes in Linux containers
(e.g., /dev/null, /dev/random, /dev/tty, etc.)
However if the container's OCI spec includes all or a subset of those same devices,
runc is currently not detecting the redundancy, causing it to create a lib
container config that has redundant device configurations.
This causes a failure in rootless mode, in particular when the /dev/tty device
has a redundant config:
container_linux.go:370: starting container process caused: process_linux.go:459: container init caused: rootfs_linux.go:70: creating device nodes caused: open /tmp/busyboxtest/rootfs/dev/tty: no such device or address"
The reason this fails in rootless mode only is that in this case runc sets up
/dev/tty not by doing mknod (it's not allowed within a user-ns) but rather by
creating a regular file under /dev/tty and bind-mounting the host's /dev/tty to
the container's /dev/tty. When this operation is done redundantly, it fails the
second time.
This change fixes this problem by ensuring runc checks for redundant devices
between the OCI spec it receives and the default devices it configures. If
a redundant device is detected, the OCI spec takes priority.
The change adds both a unit test and an integration test to verify the
behavior. Without this fix, this new integration test fails as shown above.
Signed-off-by: Cesar Talledo <ctalledo@nestybox.com>
The change ensures that the passed in value of NoNewPrivileges under spec.Process
is reflected in the container config generated by specconv.CreateLibcontainerConfig
Closes#2397
Signed-off-by: Pradyumna Agrawal <pradyumnaa@vmware.com>
Some systemd properties are documented as having "Sec" suffix
(e.g. "TimeoutStopSec") but are expected to have "USec" suffix
when passed over dbus, so let's provide appropriate conversion
to improve compatibility.
This means, one can specify TimeoutStopSec with a numeric argument,
in seconds, and it will be properly converted to TimeoutStopUsec
with the argument in microseconds. As a side bonus, even float
values are converted, so e.g. TimeoutStopSec=1.5 is possible.
This turned out a bit more tricky to implement when I was
originally expected, since there are a handful of numeric
types in dbus and each one requires explicit conversion.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
In case systemd is used to set cgroups for the container,
it creates a scope unit dedicated to it (usually named
`runc-$ID.scope`).
This patch adds an ability to set arbitrary systemd properties
for the systemd unit via runtime spec annotations.
Initially this was developed as an ability to specify the
`TimeoutStopUSec` property, but later generalized to work with
arbitrary ones.
Example usage: add the following to runtime spec (config.json):
```
"annotations": {
"org.systemd.property.TimeoutStopUSec": "uint64 123456789",
"org.systemd.property.CollectMode":"'inactive-or-failed'"
},
```
and start the container (e.g. `runc --systemd-cgroup run $ID`).
The above will set the following systemd parameters:
* `TimeoutStopSec` to 2 minutes and 3 seconds,
* `CollectMode` to "inactive-or-failed".
The values are in the gvariant format (see [1]). To figure out
which type systemd expects for a particular parameter, see
systemd sources.
In particular, parameters with `USec` suffix require an `uint64`
typed argument, while gvariant assumes int32 for a numeric values,
therefore the explicit type is required.
NOTE that systemd receives the time-typed parameters as *USec
but shows them (in `systemctl show`) as *Sec. For example,
the stop timeout should be set as `TimeoutStopUSec` but
is shown as `TimeoutStopSec`.
[1] https://developer.gnome.org/glib/stable/gvariant-text.html
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
A `config.Cgroups` object is required to manipulate cgroups v1 and v2 using
libcontainer.
Export `createCgroupConfig` to allow API users to create `config.Cgroups`
objects using directly libcontainer API.
Signed-off-by: Julio Montes <julio.montes@intel.com>
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>
Since this is a runC-specific feature, this belongs here over in
opencontainers/ocitools (which is for generic OCI runtimes).
In addition, we don't create a new network namespace. This is because
currently if you want to set up a veth bridge you need CAP_NET_ADMIN in
both network namespaces' pinned user namespace to create the necessary
interfaces in each network namespace.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
This enables the support for the rootless container mode. There are many
restrictions on what rootless containers can do, so many different runC
commands have been disabled:
* runc checkpoint
* runc events
* runc pause
* runc ps
* runc restore
* runc resume
* runc update
The following commands work:
* runc create
* runc delete
* runc exec
* runc kill
* runc list
* runc run
* runc spec
* runc state
In addition, any specification options that imply joining cgroups have
also been disabled. This is due to support for unprivileged subtree
management not being available from Linux upstream.
Signed-off-by: Aleksa Sarai <asarai@suse.de>
When spec file contains duplicated namespaces, e.g.
specs: specs.Spec{
Linux: &specs.Linux{
Namespaces: []specs.Namespace{
{
Type: "pid",
},
{
Type: "pid",
Path: "/proc/1/ns/pid",
},
},
},
}
runc should report malformed spec instead of using latest one by
default, because this spec could be quite confusing.
Signed-off-by: Zhang Wei <zhangwei555@huawei.com>
Alternative of #895 , part of #892
The intension of current behavior if to create cgroup in
parent cgroup of current process, but we did this in a
wrong way, we used devices cgroup path of current process
as the default parent path for all subsystems, this is
wrong because we don't always have the same cgroup path
for all subsystems.
Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Users of libcontainer other than runc may also require parsing and
converting specification configuration files.
Since runc cannot be imported, move the relevant functions and
definitions to a separate package, libcontainer/specconv.
Signed-off-by: Ido Yariv <ido@wizery.com>
Kir Kolyshkin