It hasn't been on-by-default before, therefore it does not get locked to the
new default on yet. This has some impact on the scheduler configuration
because the plugin is now enabled by default.
Because the feature is now GA, it doesn't need to be a label on E2E tests,
which wouldn't be possible anyway once it gets removed entirely.
The pods/finalizer permission can be restricted to just updates because that is
all that matters.
The DeviceTaints rules were under the wrong feature gate check (copy-and-paste)
and must remain disabled when DRA itself becomes enabled.
As before when adding v1beta2, DRA drivers built using the
k8s.io/dynamic-resource-allocation helper packages remain compatible with all
Kubernetes release >= 1.32. The helper code picks whatever API version is
enabled from v1beta1/v1beta2/v1.
However, the control plane now depends on v1, so a cluster configuration where
only v1beta1 or v1beta2 are enabled without the v1 won't work.
If someone gains the ability to create static pods, they might try to use that
ability to run code which gets access to the resources associated with some
existing claim which was previously allocated for some other pod. Such an
attempt already fails because the claim status tracks which pods are allowed to
use the claim, the static pod is not in that list, the node is not authorized
to add it, and the kubelet checks that list before starting the pod in
195803cde5/pkg/kubelet/cm/dra/manager.go (L218-L222).
Even if the pod were started, DRA drivers typically manage node-local resources
which can already be accessed via such an attack without involving DRA. DRA
drivers which manage non-node-local resources have to consider access by a
compromised node as part of their threat model.
Nonetheless, it is better to not accept static pods which reference
ResourceClaims or ResourceClaimTemplates in the first place because there
is no valid use case for it.
This is done at different levels for defense in depth:
- configuration validation in the kubelet
- admission checking of node restrictions
- API validation
Co-authored-by: Jordan Liggitt <liggitt@google.com>
Code changes by Jordan, with one small change (resourceClaims -> resourceclaims).
Unit tests by Patrick.
Thanks to the tracker, the plugin sees all taints directly in the device
definition and can compare it against the tolerations of a request while
trying to find a device for the request.
When the feature is turnedd off, taints are ignored during scheduling.
The controller is derived from the node taint eviction controller.
In contrast to that controller it tracks the UID of pods to prevent
deleting the wrong pod when it got replaced.
