Exemplo n.º 1
0
static bool
cp_ubsan_instrument_vptr_p (tree type)
{
  if (!flag_rtti || flag_sanitize_undefined_trap_on_error)
    return false;

  if (!do_ubsan_in_current_function ())
    return false;

  if (type)
    {
      type = TYPE_MAIN_VARIANT (type);
      if (!CLASS_TYPE_P (type) || !CLASSTYPE_VTABLES (type))
	return false;
    }

  return true;
}
Exemplo n.º 2
0
void
ubsan_maybe_instrument_array_ref (tree *expr_p, bool ignore_off_by_one)
{
  if (!ubsan_array_ref_instrumented_p (*expr_p)
      && do_ubsan_in_current_function ())
    {
      tree op0 = TREE_OPERAND (*expr_p, 0);
      tree op1 = TREE_OPERAND (*expr_p, 1);
      tree e = ubsan_instrument_bounds (EXPR_LOCATION (*expr_p), op0, &op1,
					ignore_off_by_one);
      if (e != NULL_TREE)
	{
	  tree t = copy_node (*expr_p);
	  TREE_OPERAND (t, 1) = build2 (COMPOUND_EXPR, TREE_TYPE (op1),
					e, op1);
	  *expr_p = t;
	}
    }
}
Exemplo n.º 3
0
static tree
ubsan_maybe_instrument_reference_or_call (location_t loc, tree op, tree ptype,
					  enum ubsan_null_ckind ckind)
{
  if (!do_ubsan_in_current_function ())
    return NULL_TREE;

  tree type = TREE_TYPE (ptype);
  tree orig_op = op;
  bool instrument = false;
  unsigned int mina = 0;

  if (flag_sanitize & SANITIZE_ALIGNMENT)
    {
      mina = min_align_of_type (type);
      if (mina <= 1)
	mina = 0;
    }
  while ((TREE_CODE (op) == NOP_EXPR
	  || TREE_CODE (op) == NON_LVALUE_EXPR)
	 && TREE_CODE (TREE_TYPE (op)) == POINTER_TYPE)
    op = TREE_OPERAND (op, 0);
  if (TREE_CODE (op) == NOP_EXPR
      && TREE_CODE (TREE_TYPE (op)) == REFERENCE_TYPE)
    {
      if (mina && mina > min_align_of_type (TREE_TYPE (TREE_TYPE (op))))
	instrument = true;
    }
  else
    {
      if ((flag_sanitize & SANITIZE_NULL) && TREE_CODE (op) == ADDR_EXPR)
	{
	  bool strict_overflow_p = false;
	  /* tree_single_nonzero_warnv_p will not return true for non-weak
	     non-automatic decls with -fno-delete-null-pointer-checks,
	     which is disabled during -fsanitize=null.  We don't want to
	     instrument those, just weak vars though.  */
	  int save_flag_delete_null_pointer_checks
	    = flag_delete_null_pointer_checks;
	  flag_delete_null_pointer_checks = 1;
	  if (!tree_single_nonzero_warnv_p (op, &strict_overflow_p)
	      || strict_overflow_p)
	    instrument = true;
	  flag_delete_null_pointer_checks
	    = save_flag_delete_null_pointer_checks;
	}
      else if (flag_sanitize & SANITIZE_NULL)
	instrument = true;
      if (mina && mina > 1)
	{
	  if (!POINTER_TYPE_P (TREE_TYPE (op))
	      || mina > get_pointer_alignment (op) / BITS_PER_UNIT)
	    instrument = true;
	}
    }
  if (!instrument)
    return NULL_TREE;
  op = save_expr (orig_op);
  gcc_assert (POINTER_TYPE_P (ptype));
  if (TREE_CODE (ptype) == REFERENCE_TYPE)
    ptype = build_pointer_type (TREE_TYPE (ptype));
  tree kind = build_int_cst (ptype, ckind);
  tree align = build_int_cst (pointer_sized_int_node, mina);
  tree call
    = build_call_expr_internal_loc (loc, IFN_UBSAN_NULL, void_type_node,
				    3, op, kind, align);
  TREE_SIDE_EFFECTS (call) = 1;
  return fold_build2 (COMPOUND_EXPR, TREE_TYPE (op), call, op);
}
Exemplo n.º 4
0
tree
convert (tree type, tree expr)
{
  tree e = expr;
  enum tree_code code = TREE_CODE (type);
  const char *invalid_conv_diag;
  tree ret;
  location_t loc = EXPR_LOCATION (expr);

  if (type == error_mark_node
      || error_operand_p (expr))
    return error_mark_node;

  if ((invalid_conv_diag
       = targetm.invalid_conversion (TREE_TYPE (expr), type)))
    {
      error (invalid_conv_diag);
      return error_mark_node;
    }

  if (type == TREE_TYPE (expr))
    return expr;
  ret = targetm.convert_to_type (type, expr);
  if (ret)
      return ret;

  STRIP_TYPE_NOPS (e);

  if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (expr))
      && (TREE_CODE (TREE_TYPE (expr)) != COMPLEX_TYPE
	  || TREE_CODE (e) == COMPLEX_EXPR))
    return fold_convert_loc (loc, type, expr);
  if (TREE_CODE (TREE_TYPE (expr)) == ERROR_MARK)
    return error_mark_node;
  if (TREE_CODE (TREE_TYPE (expr)) == VOID_TYPE)
    {
      error ("void value not ignored as it ought to be");
      return error_mark_node;
    }

  switch (code)
    {
    case VOID_TYPE:
      return fold_convert_loc (loc, type, e);

    case INTEGER_TYPE:
    case ENUMERAL_TYPE:
      if (flag_sanitize & SANITIZE_FLOAT_CAST
	  && TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
	  && COMPLETE_TYPE_P (type)
	  && do_ubsan_in_current_function ())
	{
	  tree arg;
	  if (in_late_binary_op)
	    {
	      expr = save_expr (expr);
	      arg = expr;
	    }
	  else
	    {
	      expr = c_save_expr (expr);
	      arg = c_fully_fold (expr, false, NULL);
	    }
	  tree check = ubsan_instrument_float_cast (loc, type, expr, arg);
	  expr = fold_build1 (FIX_TRUNC_EXPR, type, expr);
	  if (check == NULL)
	    return expr;
	  return fold_build2 (COMPOUND_EXPR, TREE_TYPE (expr), check, expr);
	}
      ret = convert_to_integer (type, e);
      goto maybe_fold;

    case BOOLEAN_TYPE:
      return fold_convert_loc
	(loc, type, c_objc_common_truthvalue_conversion (input_location, expr));

    case POINTER_TYPE:
    case REFERENCE_TYPE:
      ret = convert_to_pointer (type, e);
      goto maybe_fold;

    case REAL_TYPE:
      ret = convert_to_real (type, e);
      goto maybe_fold;

    case FIXED_POINT_TYPE:
      ret = convert_to_fixed (type, e);
      goto maybe_fold;

    case COMPLEX_TYPE:
      /* If converting from COMPLEX_TYPE to a different COMPLEX_TYPE
	 and e is not COMPLEX_EXPR, convert_to_complex uses save_expr,
	 but for the C FE c_save_expr needs to be called instead.  */
      if (TREE_CODE (TREE_TYPE (e)) == COMPLEX_TYPE)
	{
	  if (TREE_CODE (e) != COMPLEX_EXPR)
	    {
	      tree subtype = TREE_TYPE (type);
	      tree elt_type = TREE_TYPE (TREE_TYPE (e));

	      if (in_late_binary_op)
		e = save_expr (e);
	      else
		e = c_save_expr (e);
	      ret
		= fold_build2_loc (loc, COMPLEX_EXPR, type,
				   convert (subtype,
					    fold_build1 (REALPART_EXPR,
							 elt_type, e)),
				   convert (subtype,
					    fold_build1 (IMAGPART_EXPR,
							 elt_type, e)));
	      goto maybe_fold;
	    }
	}
      ret = convert_to_complex (type, e);
      goto maybe_fold;

    case VECTOR_TYPE:
      ret = convert_to_vector (type, e);
      goto maybe_fold;

    case RECORD_TYPE:
    case UNION_TYPE:
      if (lang_hooks.types_compatible_p (type, TREE_TYPE (expr)))
	return e;
      break;

    default:
      break;

    maybe_fold:
      if (TREE_CODE (ret) != C_MAYBE_CONST_EXPR)
	ret = fold (ret);
      return ret;
    }

  error ("conversion to non-scalar type requested");
  return error_mark_node;
}