Problem Description:
`bhyveload -h <host-path>` may be used to grant loader access
to the <host-path> directory tree on the host. Affected versions
of bhyveload(8) do not make any attempt to restrict loader's access
to <host-path>, allowing the loader to read any file the host user
has access to.
Impact:
In the bhyveload(8) model, the host supplies a userboot.so to
boot with, but the loader scripts generally come from the guest
image. A maliciously crafted script could be used to exfiltrate
sensitive data from the host accessible to the user running
bhyhveload(8), which is often the system root.