- `Kubelet` no longer creates certain legacy iptables rules by default.
  It is possible that this will cause problems with some third-party components
  that improperly depended on those rules. If this affects you, you can run

	any NetworkPolicy whose spec.podSelector targets them. Pods that are
	targeted by NetworkPolicies accept traffic that is accepted by any of
	the NetworkPolicies (and nothing else), and pods that are not targeted
	by any NetworkPolicy accept all traffic by default.
	Action Required:
	When upgrading to Kubernetes 1.7 (and a network plugin that supports
	the new NetworkPolicy v1 semantics), to ensure full behavioral

## Changes by Kind

### Bug or Regression

- Fixed a bug that a pod may remain unscheduled if any PreFilter plugin returns nodes that do not exist. ([#124559](https://github.com/kubernetes/kubernetes/pull/124559), [@chengjoey](https://github.com/chengjoey)) [SIG Scheduling and Testing]

This release contains changes that address the following vulnerabilities:

### CVE-2021-25735: Validating Admission Webhook does not observe some previous fields

A security issue was discovered in kube-apiserver that could allow node
updates to bypass a Validating Admission Webhook. You are only affected
by this vulnerability if you run a Validating Admission Webhook for Nodes

The behavior of some watch calls to the server when filtering on fields was incorrect. If watching objects with a filter, when an update was made that no longer matched the filter a DELETE event was correctly sent. However, the object that was returned by that delete was not the (correct) version before the update, but instead, the newer version. That meant the new object was not matched by the filter. This was a regression from behavior between cached watches on the server side and uncached watches,...

external etcd endpoints passed in the `ClusterConfiguration` that have Unicode characters are no longer IDNA encoded (converted to Punycode). They are now just URL encoded as per Go's implementation of RFC-3986, have duplicate "/" removed from the URL paths, and passed like that directly to the `kube-apiserver` `--etcd-servers` flag. If you have etcd endpoints that have Unicode characters, it is advisable to encode them in advance with tooling that is fully IDNA compliant. If you don't do that, the Go standard...

  network plugins which was first widely noticed in 1.16 (though some users saw it
  earlier than that, possibly only with specific network plugins). If you were previously
  using ethtool to disable checksum offload on your primary network interface, you should
  now be able to stop doing that. ([#92035](https://github.com/kubernetes/kubernetes/pull/92035), [@danwinship](https://github.com/danwinship)) [SIG Network and Node]

    - [<code>CSIMigrationvSphere</code> feature gate has not migrated to new CRD APIs](#csimigrationvsphere-feature-gate-has-not-migrated-to-new-crd-apis)
    - [Workloads that saturate nodes with pods may see pods that fail due to node admission](#workloads-that-saturate-nodes-with-pods-may-see-pods-that-fail-due-to-node-admission)
    - [Etcd v3.5.[0-2] data corruption](#etcd-v350-2-data-corruption)
  - [Urgent Upgrade Notes](#urgent-upgrade-notes)

hence is infinite.
Similarly, given the set of all non-interface types that implement a particular method, the
intersection of the method sets of those types will contain exactly that method, even if all
types in the program at hand always pair that method with another method.
</p>

<p>
By construction, an interface's type set never contains an interface type.
</p>

Traditionally, the Kubernetes scheduler was based on the assumptions that additional persistent storage is available everywhere in the cluster and has infinite capacity. Topology constraints addressed the first point, but up to now pod scheduling was still done without considering that the remaining storage capacity may not be enough to start a new pod. [Storage capacity tracking](https://docs.k8s.io/concepts/storage/storage-capacity/) addresses that by adding an API for a CSI driver to report storage capacity...