[PATCH 5.8 071/633] KVM: nVMX: Reload vmcs01 if getting vmcs12s pages fails

[Greg Kroah-Hartman]

From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>

commit b89d5ad00e789967a5e2c5335f75c48755bebd88 upstream.

Reload vmcs01 when bailing from nested_vmx_enter_non_root_mode() as KVM
expects vmcs01 to be loaded when is_guest_mode() is false.

Fixes: 671ddc700fd08 ("KVM: nVMX: Don't leak L1 MMIO regions to L2")
Cc: stable@xxxxxxxxxxxxxxx
Cc: Dan Cross <dcross@xxxxxxxxxx>
Cc: Jim Mattson <jmattson@xxxxxxxxxx>
Cc: Peter Shier <pshier@xxxxxxxxxx>
Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Message-Id: <20200923184452.980-3-sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/x86/kvm/vmx/nested.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -3297,8 +3297,10 @@ enum nvmx_vmentry_status nested_vmx_ente
 	prepare_vmcs02_early(vmx, vmcs12);
 
 	if (from_vmentry) {
-		if (unlikely(!nested_get_vmcs12_pages(vcpu)))
+		if (unlikely(!nested_get_vmcs12_pages(vcpu))) {
+			vmx_switch_vmcs(vcpu, &vmx->vmcs01);
 			return NVMX_VMENTRY_KVM_INTERNAL_ERROR;
+		}
 
 		if (nested_vmx_check_vmentry_hw(vcpu)) {
 			vmx_switch_vmcs(vcpu, &vmx->vmcs01);