<h3 id="Type_unification_rules">Type unification rules</h3>

<p>
The type unification rules describe if and how two types unify.
The precise details are relevant for Go implementations,
affect the specifics of error messages (such as whether
a compiler reports a type inference or other error),
and may explain why type inference fails in unusual code situations.
But by and large these rules can be ignored when writing Go code:

#### **RBAC**

*   New permissions have been added to default RBAC roles ([#52654](https://github.com/kubernetes/kubernetes/pull/52654),[ @liggitt](https://github.com/liggitt)):
    *   The default admin and edit roles now include read/write permissions
    *   The view role includes read permissions on poddisruptionbudget.policy resources.

  // +optional
  optional bool readOnly = 4;
}

// Affinity is a group of affinity scheduling rules.
message Affinity {
  // Describes node affinity scheduling rules for the pod.
  // +optional
  optional NodeAffinity nodeAffinity = 1;

  // Describes pod affinity scheduling rules (e.g. co-locate this pod in the same node, zone, etc. as some other pod(s)).
  // +optional
  optional PodAffinity podAffinity = 2;

- Drop additional rule requirement (cronjobs/finalizers) in the roles who use kubectl create cronjobs to be backwards compatible ([#124883](https://github.com/kubernetes/kubernetes/pull/124883), [@ardaguclu](https://github.com/ardaguclu)) [SIG CLI]

- In "large" clusters, kube-proxy in iptables mode will now sometimes
  leave unused rules in iptables for a while (up to `--iptables-sync-period`)
  before deleting them. This improves performance by not requiring it to
  check for stale rules on every sync. (In smaller clusters, it will still
  remove unused rules immediately once they are no longer used.)

- Change GCP ILB firewall names to contain the `k8s-fw-` prefix like the rest of the firewall rules. This is needed for consistency and also for other components to identify the firewall rule as k8s/service-controller managed. ([#84622](https://github.com/kubernetes/kubernetes/pull/84622), [@prameshj](https://github.com/prameshj))

- Fixed bug in CRD Validation Rules (beta) and `ValidatingAdmissionPolicy` (alpha) where all admission requests could result in `internal error: runtime error: index out of range [3] with length 3 evaluating rule: <rule name>` under certain circumstances. ([#114857](https://github.com/kubernetes/kubernetes/pull/114857), [@jpbetz](https://github.com/jpbetz))

- Fixed a bug where kube-proxy returns error due to existing ipset rules using a different hash type. ([#77371](https://github.com/kubernetes/kubernetes/pull/77371), [@andrewsykim](https://github.com/andrewsykim))
- Fixed spurious error messages about failing to clean up iptables rules when using iptables 1.8. ([#77303](https://github.com/kubernetes/kubernetes/pull/77303), [@danwinship](https://github.com/danwinship))

* Ensure the backend pools are set correctly for Azure SLB with multiple backend pools (e.g. outbound rules) ([#76691](https://github.com/kubernetes/kubernetes/pull/76691), [@feiskyer](https://github.com/feiskyer))

* The builtin system:csi-external-provisioner and system:csi-external-attacher cluster roles are deprecated and will not be updated for deployments of CSI sidecar container versions >= 0.4. Deployments with the current CSI sidecar containers have to provide their own RBAC definitions. The reason is that the rules depend on how the sidecar containers are used, which is defined by the deployment. ([#69868](https://github.com/kubernetes/kubernetes/pull/69868),...