- kubeadm: fall back to client version in case of certain HTTP errors ([#80024](https://github.com/kubernetes/kubernetes/pull/80024), [@RainbowMango](https://github.com/RainbowMango))
- kubeadm: fix a potential panic if kubeadm discovers an invalid, existing kubeconfig file ([#79165](https://github.com/kubernetes/kubernetes/pull/79165), [@neolit123](https://github.com/neolit123))

- Kubeadm: avoid panicing if the user has malformed the kubeconfig in the cluster-info config map to not include a valid current context. Include proper validation at the appropriate locations and throw errors instead. ([#134725](https://github.com/kubernetes/kubernetes/pull/134725), [@neolit123](https://github.com/neolit123)) [SIG Cluster Lifecycle]

## Changelog since v1.12.4

### Other notable changes

* kubectl: fixed an issue with "too old resource version" errors continuously appearing when calling `kubectl delete` ([#72825](https://github.com/kubernetes/kubernetes/pull/72825), [@liggitt](https://github.com/liggitt))

                }
            } catch (SmbException e) {
                // Ignore listing errors during cleanup
                log.debug("Error listing files during cleanup", e);
            }
        }

        try {
            file.delete();
        } catch (SmbException e) {
            // Ignore deletion errors during cleanup
            log.debug("Error deleting file during cleanup", e);
        }

- Fixes a regression in kube-apiserver causing 500 errors from the `/readyz` endpoint ([#93643](https://github.com/kubernetes/kubernetes/pull/93643), [@ialidzhikov](https://github.com/ialidzhikov)) [SIG API Machinery]

- The `kube-apiserver` will now expose four new metrics to inform about errors on the clusterIP and nodePort allocation logic. ([#120843](https://github.com/kubernetes/kubernetes/pull/120843), [@aojea](https://github.com/aojea))

   *     underlying this step or, if {@code get()} throws a different kind of exception, that
   *     exception itself. To avoid hiding bugs and other unrecoverable errors, callers should
   *     prefer more specific types, avoiding {@code Throwable.class} in particular.
   * @param fallback the function to be called if this step fails with the expected exception type.

### Bug or Regression

- Fixed a bug where clusters that use KMS v1 with skewed API servers on versions v1.24 and v1.25 would see internal errors when attempting to read encrypted data via the v1.24 API servers. ([#119387](https://github.com/kubernetes/kubernetes/pull/119387), [@enj](https://github.com/enj)) [SIG API Machinery and Auth]

## Dependencies

### Added

- github.com/cncf/udpa/go: [5459f2c](https://github.com/cncf/udpa/go/tree/5459f2c)
- github.com/cockroachdb/errors: [v1.2.4](https://github.com/cockroachdb/errors/tree/v1.2.4)
- github.com/cockroachdb/logtags: [eb05cc2](https://github.com/cockroachdb/logtags/tree/eb05cc2)
- github.com/coredns/caddy: [v1.1.0](https://github.com/coredns/caddy/tree/v1.1.0)

   * structure (to make it possible to throw ConcurrentModificationException in the iterator). Note
   * that we choose not to make this volatile, so we do less of a "best effort" to track such
   * errors, for better performance.
   */
  private transient int metadata;

  /** The number of elements contained in the set. */
  private transient int size;