diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 23170b64f4a3..fb2174b6d1ba 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -4497,13 +4497,17 @@ int sev_handle_vmgexit(struct kvm_vcpu *vcpu)
 	case SVM_VMGEXIT_MMIO_READ:
 	case SVM_VMGEXIT_MMIO_WRITE: {
 		bool is_write = control->exit_code == SVM_VMGEXIT_MMIO_WRITE;
+		u64 len = control->exit_info_2;
 
-		ret = setup_vmgexit_scratch(svm, !is_write, control->exit_info_2);
+		if (!len)
+			return 1;
+
+		ret = setup_vmgexit_scratch(svm, !is_write, len);
 		if (ret)
 			break;
 
-		ret = kvm_sev_es_mmio(vcpu, is_write, control->exit_info_1,
-				      control->exit_info_2, svm->sev_es.ghcb_sa);
+		ret = kvm_sev_es_mmio(vcpu, is_write, control->exit_info_1, len,
+				      svm->sev_es.ghcb_sa);
 		break;
 	}
 	case SVM_VMGEXIT_NMI_COMPLETE: