KVM: VMX: Resume guest immediately when injecting #GP on ECREATE

commit eb3992e833d3a17f9b0a3e0371d0b1d3d566f740 upstream.

Resume the guest immediately when injecting a #GP on ECREATE due to an
invalid enclave size, i.e. don't attempt ECREATE in the host.  The #GP is
a terminal fault, e.g. skipping the instruction if ECREATE is successful
would result in KVM injecting #GP on the instruction following ECREATE.

Fixes: 70210c044b4e ("KVM: VMX: Add SGX ENCLS[ECREATE] handler to enforce CPUID restrictions")
Cc: stable@vger.kernel.org
Cc: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Link: https://lore.kernel.org/r/20220930233132.1723330-1-seanjc@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kvm/vmx/sgx.c b/arch/x86/kvm/vmx/sgx.c
index 6693ebd..b8cf9a5 100644 (file)
--- a/arch/x86/kvm/vmx/sgx.c
+++ b/arch/x86/kvm/vmx/sgx.c
@@ -188,8 +188,10 @@ static int __handle_encls_ecreate(struct kvm_vcpu *vcpu,
        /* Enforce CPUID restriction on max enclave size. */
        max_size_log2 = (attributes & SGX_ATTR_MODE64BIT) ? sgx_12_0->edx >> 8 :
                                                            sgx_12_0->edx;
-       if (size >= BIT_ULL(max_size_log2))
+       if (size >= BIT_ULL(max_size_log2)) {
                kvm_inject_gp(vcpu, 0);
+               return 1;
+       }
 
        /*
         * sgx_virt_ecreate() returns: