[PATCH 1/2] KVM: VMX: Inject #GP on ENCLS if vCPU has paging disabled (CR0.PG==0)

From: Sean Christopherson
Date: Wed Apr 05 2023 - 19:46:14 EST


Inject a #GP when emulating/forwarding a valid ENCLS leaf if the vCPU has
paging disabled, e.g. if KVM is intercepting ECREATE to enforce additional
restrictions. The pseudocode in the SDM lists all #GP triggers, including
CR0.PG=0, as being checked after the ENLCS-exiting checks, i.e. the
VM-Exit will occur before the CPU performs the CR0.PG check.

Fixes: 70210c044b4e ("KVM: VMX: Add SGX ENCLS[ECREATE] handler to enforce CPUID restrictions")
Cc: Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx>
Cc: Kai Huang <kai.huang@xxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/vmx/sgx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/sgx.c b/arch/x86/kvm/vmx/sgx.c
index aa53c98034bf..f881f6ff6408 100644
--- a/arch/x86/kvm/vmx/sgx.c
+++ b/arch/x86/kvm/vmx/sgx.c
@@ -375,7 +375,7 @@ int handle_encls(struct kvm_vcpu *vcpu)

if (!encls_leaf_enabled_in_guest(vcpu, leaf)) {
kvm_queue_exception(vcpu, UD_VECTOR);
- } else if (!sgx_enabled_in_guest_bios(vcpu)) {
+ } else if (!sgx_enabled_in_guest_bios(vcpu) || !is_paging(vcpu)) {
kvm_inject_gp(vcpu, 0);
} else {
if (leaf == ECREATE)
--
2.40.0.348.gf938b09366-goog