Commit 02761716 authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Paolo Bonzini
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KVM: nVMX: Release eVMCS when enlightened VMENTRY was disabled 



In theory, L1 can try to disable enlightened VMENTRY in VP assist page and
try to issue VMLAUNCH/VMRESUME. While nested_vmx_handle_enlightened_vmptrld()
properly handles this as 'EVMPTRLD_DISABLED', previously mapped eVMCS
remains mapped and thus all evmptr_is_valid() checks will still pass and
nested_vmx_run() will proceed when it shouldn't.

Release eVMCS immediately when we detect that enlightened vmentry was
disabled by L1.

Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210526132026.270394-4-vkuznets@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 6a789ca5

arch/x86/kvm/vmx/nested.c

+3 −1
Original line number Diff line number Diff line
@@ -1979,8 +1979,10 @@ static enum nested_evmptrld_status nested_vmx_handle_enlightened_vmptrld( 
	if (likely(!vmx->nested.enlightened_vmcs_enabled))

		return EVMPTRLD_DISABLED;



	if (!nested_enlightened_vmentry(vcpu, &evmcs_gpa))

	if (!nested_enlightened_vmentry(vcpu, &evmcs_gpa)) {

		nested_release_evmcs(vcpu);

		return EVMPTRLD_DISABLED;

	}



	if (unlikely(evmcs_gpa != vmx->nested.hv_evmcs_vmptr)) {

		vmx->nested.current_vmptr = -1ull;