For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. Since Xen itself needs to be mapped when PV guests run, Xen and shadowed PV guests run directly the respective shadow page tables. For 64-bit PV guests this means running on the shadow of the guest root page table. In the course of dealing with shortage of memory in the shadow pool associated with a domain, shadows of page tables may be torn down. This tearing down may include the shadow root page table that the CPU in question is presently running on. While a precaution exists to supposedly prevent the tearing down of the underlying live page table, the time window covered by that precaution isn't large enough.
oryginał ENCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HXen
OSXen3.2.0 – 4.15.0 (bez)
Powiązane podatności
Xen: NULL pointer dereference w obsłudze syntetycznych timerów viridian
Błąd NULL pointer dereference w kodzie viridian hiperwizora Xen
Race condition w Xen viridian — zwolnienie strony obecnej w tablicach p2m
An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by...
An issue was discovered in Xen 4.7 through 4.10.x. libxl fails to pass the readonly flag to qemu when setting ...