Уязвимость подсистемы KVM AMD для поддержки вложенной виртуализации SVM ядра операционной системы Linux, позволяющая нарушителю вызвать отказ в обслуживании

Уязвимость функции efivar_ssdt_load() модуля drivers/firmware/efi/efi.c драйвера прошивок ядра операционной системы Linux, позволяющая нарушителю оказать воздействие на конфиденциальность, целостность и доступность защищаемой информации

A flaw was found in the KVM's AMD nested virtualization (SVM). A malicious L1 guest could purposely fail to intercept the shutdown of a cooperative nested guest (L2), possibly leading to a page fault and kernel panic in the host (L0).

In the Linux kernel, the following vulnerability has been resolved: efi: ssdt: Don't free memory if ACPI table was loaded successfully Amadeusz reports KASAN use-after-free errors introduced by commit 3881ee0b1edc ("efi: avoid efivars layer when loading SSDTs from variables"). The problem appears to be that the memory that holds the new ACPI table is now freed unconditionally, instead of only when the ACPI core reported a failure to load the table. So let's fix this, by omitting the kfree() on success.