static int init_kvm_nested_mmu(struct kvm_vcpu *vcpu)
{
	struct kvm_mmu *g_context = &vcpu->arch.nested_mmu;

	g_context->get_cr3           = get_cr3;
	g_context->get_pdptr         = kvm_pdptr_read;
	g_context->inject_page_fault = kvm_inject_page_fault;

	/*
	 * Note that arch.mmu.gva_to_gpa translates l2_gva to l1_gpa. The
	 * translation of l2_gpa to l1_gpa addresses is done using the
	 * arch.nested_mmu.gva_to_gpa function. Basically the gva_to_gpa
	 * functions between mmu and nested_mmu are swapped.
	 */
	if (!is_paging(vcpu)) {
		g_context->nx = false;
		g_context->root_level = 0;
		g_context->gva_to_gpa = nonpaging_gva_to_gpa_nested;
	} else if (is_long_mode(vcpu)) {
		g_context->nx = is_nx(vcpu);
		g_context->root_level = PT64_ROOT_LEVEL;
		reset_rsvds_bits_mask(vcpu, g_context);
		g_context->gva_to_gpa = paging64_gva_to_gpa_nested;
	} else if (is_pae(vcpu)) {
		g_context->nx = is_nx(vcpu);
		g_context->root_level = PT32E_ROOT_LEVEL;
		reset_rsvds_bits_mask(vcpu, g_context);
		g_context->gva_to_gpa = paging64_gva_to_gpa_nested;
	} else {
		g_context->nx = false;
		g_context->root_level = PT32_ROOT_LEVEL;
		reset_rsvds_bits_mask(vcpu, g_context);
		g_context->gva_to_gpa = paging32_gva_to_gpa_nested;
	}

	update_permission_bitmask(vcpu, g_context, false);
	update_last_pte_bitmap(vcpu, g_context);

	return 0;
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.