slightly stricter about what values will be accepted as IP addresses and network
  address ranges (“CIDR blocks”).
  
  In particular, octets within IPv4 addresses are not allowed to have any leading
  `0`s, and IPv4-mapped IPv6 values (e.g. `::ffff:192.168.0.1`) are forbidden.
  These sorts of values can potentially cause security problems when different

  * Report same Node IP as both internal and external. ([#45201](https://github.com/kubernetes/kubernetes/pull/45201), [@abrarshivani](https://github.com/abrarshivani))

  * Filter out IPV6 node addresses. ([#45181](https://github.com/kubernetes/kubernetes/pull/45181), [@BaluDontu](https://github.com/BaluDontu))

- Kube-proxy: Checked whether IPv6 was available on Linux before using it. ([#131265](https://github.com/kubernetes/kubernetes/pull/131265), [@rikatz](https://github.com/rikatz))

- Fixed a regression in kube-proxy where it might refuse to start if given
  single-stack IPv6 configuration options on a node that has both IPv4 and
  IPv6 IPs. ([#121008](https://github.com/kubernetes/kubernetes/pull/121008), [@danwinship](https://github.com/danwinship)) [SIG Network]

- Kube-proxy doesn't set the sysctl `net.ipv4.conf.all.route_localnet=1` if no IPv4 loopback address is selected by the `nodePortAddresses` configuration parameter. ([#107684](https://github.com/kubernetes/kubernetes/pull/107684), [@aojea](https://github.com/aojea))

### OpenStack

* Fixed a bug in the OpenStack cloud provider where dual stack deployments (IPv4 and IPv6) did not work well when using kubenet as the network plugin. ([#59749](https://github.com/kubernetes/kubernetes/pull/59749), [@zioproto](https://github.com/zioproto))

- Fix a bug that caused to panic the apiserver when trying to allocate a Service with a dynamic ClusterIP and it has been configured with Service CIDRs with a /28 mask for IPv4 and a /124 mask for IPv6 ([#115333](https://github.com/kubernetes/kubernetes/pull/115333), [@aojea](https://github.com/aojea)) [SIG Testing]

- Fixed mounting of NFS volumes when IPv6 address is used as a server. ([#101067](https://github.com/kubernetes/kubernetes/pull/101067), [@Elbehery](https://github.com/Elbehery)) [SIG Storage]

* You can now use `--ipvs-exclude-cidrs` to specify a list of CIDR's which the IPVS proxier should not touch when cleaning up IPVS rules. ([#62083](https://github.com/kubernetes/kubernetes/pull/62083), [@rramkumar1](https://github.com/rramkumar1))

- Added support to the kube-proxy nodePortAddresses / --nodeport-addresses option to
  accept the value "primary", meaning to only listen for NodePort connections
  on the node's primary IPv4 and/or IPv6 address (according to the Node object).
  This is strongly recommended, if you were not previously using
  --nodeport-addresses, to avoid surprising behavior.