Commit c3a1e119 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: VMX: Inject #GP, not #UD, if SGX2 ENCLS leafs are unsupported 



Per Intel's SDM, unsupported ENCLS leafs result in a #GP, not a #UD.
SGX1 is a special snowflake as the SGX1 flag is used by the CPU as a
"soft" disable, e.g. if software disables machine check reporting, i.e.
having SGX but not SGX1 is effectively "SGX completely unsupported" and
and thus #UDs.

Fixes: 9798adbc ("KVM: VMX: Frame in ENCLS handler for SGX virtualization")
Cc: Binbin Wu <binbin.wu@linux.intel.com>
Cc: Kai Huang <kai.huang@intel.com>
Tested-by: default avatarKai Huang <kai.huang@intel.com>
Reviewed-by: default avatarKai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20230405234556.696927-3-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 5e50082c

arch/x86/kvm/vmx/sgx.c

+9 −6
Original line number Diff line number Diff line
@@ -357,11 +357,12 @@ static int handle_encls_einit(struct kvm_vcpu *vcpu) 


static inline bool encls_leaf_enabled_in_guest(struct kvm_vcpu *vcpu, u32 leaf)

{

	if (!enable_sgx || !guest_cpuid_has(vcpu, X86_FEATURE_SGX))

		return false;



	/*

	 * ENCLS generates a #UD if SGX1 isn't supported, i.e. this point will

	 * be reached if and only if the SGX1 leafs are enabled.

	 */

	if (leaf >= ECREATE && leaf <= ETRACK)

		return guest_cpuid_has(vcpu, X86_FEATURE_SGX1);

		return true;



	if (leaf >= EAUG && leaf <= EMODT)

		return guest_cpuid_has(vcpu, X86_FEATURE_SGX2);
@@ -380,9 +381,11 @@ int handle_encls(struct kvm_vcpu *vcpu) 
{

	u32 leaf = (u32)kvm_rax_read(vcpu);



	if (!encls_leaf_enabled_in_guest(vcpu, leaf)) {

	if (!enable_sgx || !guest_cpuid_has(vcpu, X86_FEATURE_SGX) ||

	    !guest_cpuid_has(vcpu, X86_FEATURE_SGX1)) {

		kvm_queue_exception(vcpu, UD_VECTOR);

	} else if (!sgx_enabled_in_guest_bios(vcpu) || !is_paging(vcpu)) {

	} else if (!encls_leaf_enabled_in_guest(vcpu, leaf) ||

		   !sgx_enabled_in_guest_bios(vcpu) || !is_paging(vcpu)) {

		kvm_inject_gp(vcpu, 0);

	} else {

		if (leaf == ECREATE)