OpenBSD Errata: February 17th, 2020 (vmm_pvclock)

Errata patches for vmm have been released for OpenBSD 6.6.

A missing range check in the vmm pvclock allows a guest to write
to host memory.

Binary updates for the amd64 platform are available via the syspatch
utility. Source code patches can be found on the errata page:

  https://www.openbsd.org/errata66.html

As these affect the kernel, a reboot will be needed after patching.