MyNixOS website logo
Description

Xen Project Hypervisor and related components (Standard)

Standard version of the Xen Project Hypervisor. Uses forks of QEMU, SeaBIOS, OVMF and iPXE provided by the Xen Project. This provides the vanilla Xen experience, but wastes space and build time. A typical NixOS setup that runs lots of VMs will usually need to build two different versions of QEMU when using this Xen derivation (one fork and upstream).

Includes:

  • xen.efi: The Xen Project's EFI binary, available on the boot output of this package.
  • qemu-xen: The Xen Project's mirror of QEMU.
  • seabios-xen: The Xen Project's mirror of SeaBIOS.
  • ovmf-xen: The Xen Project's mirror of OVMF.
  • ipxe-xen: The Xen Project's pinned version of iPXE.

This Xen Project Hypervisor (4.17.5) has been patched against the following known security vulnerabilities:

  • Xen Security Advisory #462: x86: Deadlock in vlapic_error().

    In x86's APIC (Advanced Programmable Interrupt Controller) architecture, error conditions are reported in a status register. Furthermore, the OS can opt to receive an interrupt when a new error occurs.

It is possible to configure the error interrupt with an illegal vector, which generates an error when an error interrupt is raised.

This case causes Xen to recurse through vlapic_error(). The recursion itself is bounded; errors accumulate in the the status register and only generate an interrupt when a new status bit becomes set.

However, the lock protecting this state in Xen will try to be taken recursively, and deadlock.

Fixes: