* Fix pods failing to start if they specify a file as a volume subPath to mount. ([#46046](https://github.com/kubernetes/kubernetes/pull/46046), [@enisoc](https://github.com/enisoc))



# v1.6.3

[Documentation](https://docs.k8s.io) & [Examples](https://releases.k8s.io/release-1.6/examples)

## Known Issues for v1.6.3

## Changelog since v1.7.15

### Action Required

* ACTION REQUIRED: In-place node upgrades to this release from versions 1.7.14, 1.8.9, and 1.9.4 are not supported if using subpath volumes with PVCs.  Such pods should be drained from the node first. ([#61373](https://github.com/kubernetes/kubernetes/pull/61373), [@msau42](https://github.com/msau42))

### Other notable changes

* Bump version of prometheus-to-sd to 0.2.6 to decrease log noise and include latest security patches. ([#64963](https://github.com/kubernetes/kubernetes/pull/64963), [@loburm](https://github.com/loburm))
* Fixes issue for readOnly subpath mounts for SELinux systems and when the volume mountPath already existed in the container image. ([#64351](https://github.com/kubernetes/kubernetes/pull/64351), [@msau42](https://github.com/msau42))

- Make sure auto-mounted subpath mount source is already mounted ([#112499](https://github.com/kubernetes/kubernetes/pull/112499), [@andyzhangx](https://github.com/andyzhangx)) [SIG Storage]

## Dependencies

### Added
_Nothing has changed._

* Reimplement 'pause' in C - smaller footprint all around ([#23009](https://github.com/kubernetes/kubernetes/pull/23009), [@uluyol](https://github.com/uluyol))
* Add subPath to mount a child dir or file of a volumeMount ([#22575](https://github.com/kubernetes/kubernetes/pull/22575), [@MikaelCluseau](https://github.com/MikaelCluseau))

* Fix kube-controller-manager panic while provisioning Azure security group rules ([#64739](https://github.com/kubernetes/kubernetes/pull/64739), [@feiskyer](https://github.com/feiskyer))
* Fixes issue for readOnly subpath mounts for SELinux systems and when the volume mountPath already existed in the container image. ([#64351](https://github.com/kubernetes/kubernetes/pull/64351), [@msau42](https://github.com/msau42))

* Implement TLS bootstrap for kubelet using `--experimental-bootstrap-kubeconfig`  (2nd take) ([#30922](https://github.com/kubernetes/kubernetes/pull/30922), [@yifan-gu](https://github.com/yifan-gu))
* rkt: Support subPath volume mounts feature ([#30934](https://github.com/kubernetes/kubernetes/pull/30934), [@yifan-gu](https://github.com/yifan-gu))

   ([#119923](https://github.com/kubernetes/kubernetes/pull/119923), [@cvvz](https://github.com/cvvz))
- Fixed cleanup of Pod volume mounts when a file was used as a subpath.
   ([#123052](https://github.com/kubernetes/kubernetes/pull/123052), [@jsafrane](https://github.com/jsafrane))
- Fixed error handling in `EnsureAdminClusterRoleBindingImpl`.

* Fixes issue with cleaning up stale NFS subpath mounts ([#71804](https://github.com/kubernetes/kubernetes/pull/71804), [@msau42](https://github.com/msau42))

### CVE-2021-25741: Symlink Exchange Can Allow Host Filesystem Access

A security issue was discovered in Kubernetes where a user may be able to
create a container with subpath volume mounts to access files &
directories outside of the volume, including on the host filesystem.

**Affected Versions**:
  - kubelet v1.22.0 - v1.22.1
  - kubelet v1.21.0 - v1.21.4
  - kubelet v1.20.0 - v1.20.10