XENCVELIST:CVE-2023-46842CVE-2023-46842 x86 HVM hypercalls may trigger Xen bug check
Unlike 32-bit PV guests, HVM guests may switch freely between 64-bit and
other modes. This in particular means that they may set registers used
to pass 32-bit-mode hypercall arguments to values outside of the range
32-bit code would be able to set them to.
When processing of hypercalls takes a considerable amount of time,
the hypervisor may choose to invoke a hypercall continuation. Doing so
involves putting (perhaps updated) hypercall arguments in respective
registers. For guests not running in 64-bit mode this further involves
a certain amount of translation of the values.
Unfortunately internal sanity checking of these translated values
assumes high halves of registers to always be clear when invoking a
hypercall. When this is found not to be the case, it triggers a
consistency check in the hypervisor and causes a crash.
CNA Affected
[
{
"defaultStatus": "unknown",
"product": "Xen",
"vendor": "Xen",
"versions": [
{
"status": "unknown",
"version": "consult Xen advisory XSA-454"
}
]
}
]Related
