[PATCH 05/14] KVM: x86: nSVM: don't copy virt_ext from vmcb12

From: Maxim Levitsky
Date: Tue Sep 14 2021 - 11:49:38 EST


These field correspond to features that we don't expose yet to L2

While currently there are no CVE worthy features in this field,
if AMD adds more features to this field, that could allow guest
escapes similar to CVE-2021-3653 and CVE-2021-3656.

Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
---
arch/x86/kvm/svm/nested.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 476e01f98035..4df59d9795b6 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -545,7 +545,6 @@ static void nested_vmcb02_prepare_control(struct vcpu_svm *svm)
(svm->nested.ctl.int_ctl & int_ctl_vmcb12_bits) |
(svm->vmcb01.ptr->control.int_ctl & int_ctl_vmcb01_bits);

- svm->vmcb->control.virt_ext = svm->nested.ctl.virt_ext;
svm->vmcb->control.int_vector = svm->nested.ctl.int_vector;
svm->vmcb->control.int_state = svm->nested.ctl.int_state;
svm->vmcb->control.event_inj = svm->nested.ctl.event_inj;
--
2.26.3