acpi/acpica/nspredef.c

0001 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
0002 /******************************************************************************
0003  *
0004  * Module Name: nspredef - Validation of ACPI predefined methods and objects
0005  *
0006  * Copyright (C) 2000 - 2022, Intel Corp.
0007  *
0008  *****************************************************************************/
0009
0010 #define ACPI_CREATE_PREDEFINED_TABLE
0011
0012 #include <acpi/acpi.h>
0013 #include "accommon.h"
0014 #include "acnamesp.h"
0015 #include "acpredef.h"
0016
0017 #define _COMPONENT          ACPI_NAMESPACE
0018 ACPI_MODULE_NAME("nspredef")
0019
0020 /*******************************************************************************
0021  *
0022  * This module validates predefined ACPI objects that appear in the namespace,
0023  * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
0024  * validation is to detect problems with BIOS-exposed predefined ACPI objects
0025  * before the results are returned to the ACPI-related drivers.
0026  *
0027  * There are several areas that are validated:
0028  *
0029  *  1) The number of input arguments as defined by the method/object in the
0030  *     ASL is validated against the ACPI specification.
0031  *  2) The type of the return object (if any) is validated against the ACPI
0032  *     specification.
0033  *  3) For returned package objects, the count of package elements is
0034  *     validated, as well as the type of each package element. Nested
0035  *     packages are supported.
0036  *
0037  * For any problems found, a warning message is issued.
0038  *
0039  ******************************************************************************/
0040 /* Local prototypes */
0041 static acpi_status
0042 acpi_ns_check_reference(struct acpi_evaluate_info *info,
0043             union acpi_operand_object *return_object);
0044
0045 static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object);
0046
0047 /*******************************************************************************
0048  *
0049  * FUNCTION:    acpi_ns_check_return_value
0050  *
0051  * PARAMETERS:  node            - Namespace node for the method/object
0052  *              info            - Method execution information block
0053  *              user_param_count - Number of parameters actually passed
0054  *              return_status   - Status from the object evaluation
0055  *              return_object_ptr - Pointer to the object returned from the
0056  *                                evaluation of a method or object
0057  *
0058  * RETURN:      Status
0059  *
0060  * DESCRIPTION: Check the value returned from a predefined name.
0061  *
0062  ******************************************************************************/
0063
0064 acpi_status
0065 acpi_ns_check_return_value(struct acpi_namespace_node *node,
0066                struct acpi_evaluate_info *info,
0067                u32 user_param_count,
0068                acpi_status return_status,
0069                union acpi_operand_object **return_object_ptr)
0070 {
0071     acpi_status status;
0072     const union acpi_predefined_info *predefined;
0073
0074     ACPI_FUNCTION_TRACE(ns_check_return_value);
0075
0076     /* If not a predefined name, we cannot validate the return object */
0077
0078     predefined = info->predefined;
0079     if (!predefined) {
0080         return_ACPI_STATUS(AE_OK);
0081     }
0082
0083     /*
0084      * If the method failed or did not actually return an object, we cannot
0085      * validate the return object
0086      */
0087     if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
0088         return_ACPI_STATUS(AE_OK);
0089     }
0090
0091     /*
0092      * Return value validation and possible repair.
0093      *
0094      * 1) Don't perform return value validation/repair if this feature
0095      * has been disabled via a global option.
0096      *
0097      * 2) We have a return value, but if one wasn't expected, just exit,
0098      * this is not a problem. For example, if the "Implicit Return"
0099      * feature is enabled, methods will always return a value.
0100      *
0101      * 3) If the return value can be of any type, then we cannot perform
0102      * any validation, just exit.
0103      */
0104     if (acpi_gbl_disable_auto_repair ||
0105         (!predefined->info.expected_btypes) ||
0106         (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
0107         return_ACPI_STATUS(AE_OK);
0108     }
0109
0110     /*
0111      * Check that the type of the main return object is what is expected
0112      * for this predefined name
0113      */
0114     status = acpi_ns_check_object_type(info, return_object_ptr,
0115                        predefined->info.expected_btypes,
0116                        ACPI_NOT_PACKAGE_ELEMENT);
0117     if (ACPI_FAILURE(status)) {
0118         goto exit;
0119     }
0120
0121     /*
0122      *
0123      * 4) If there is no return value and it is optional, just return
0124      * AE_OK (_WAK).
0125      */
0126     if (!(*return_object_ptr)) {
0127         goto exit;
0128     }
0129
0130     /*
0131      * For returned Package objects, check the type of all sub-objects.
0132      * Note: Package may have been newly created by call above.
0133      */
0134     if ((*return_object_ptr)->common.type == ACPI_TYPE_PACKAGE) {
0135         info->parent_package = *return_object_ptr;
0136         status = acpi_ns_check_package(info, return_object_ptr);
0137         if (ACPI_FAILURE(status)) {
0138
0139             /* We might be able to fix some errors */
0140
0141             if ((status != AE_AML_OPERAND_TYPE) &&
0142                 (status != AE_AML_OPERAND_VALUE)) {
0143                 goto exit;
0144             }
0145         }
0146     }
0147
0148     /*
0149      * The return object was OK, or it was successfully repaired above.
0150      * Now make some additional checks such as verifying that package
0151      * objects are sorted correctly (if required) or buffer objects have
0152      * the correct data width (bytes vs. dwords). These repairs are
0153      * performed on a per-name basis, i.e., the code is specific to
0154      * particular predefined names.
0155      */
0156     status = acpi_ns_complex_repairs(info, node, status, return_object_ptr);
0157
0158 exit:
0159     /*
0160      * If the object validation failed or if we successfully repaired one
0161      * or more objects, mark the parent node to suppress further warning
0162      * messages during the next evaluation of the same method/object.
0163      */
0164     if (ACPI_FAILURE(status) || (info->return_flags & ACPI_OBJECT_REPAIRED)) {
0165         node->flags |= ANOBJ_EVALUATED;
0166     }
0167
0168     return_ACPI_STATUS(status);
0169 }
0170
0171 /*******************************************************************************
0172  *
0173  * FUNCTION:    acpi_ns_check_object_type
0174  *
0175  * PARAMETERS:  info            - Method execution information block
0176  *              return_object_ptr - Pointer to the object returned from the
0177  *                                evaluation of a method or object
0178  *              expected_btypes - Bitmap of expected return type(s)
0179  *              package_index   - Index of object within parent package (if
0180  *                                applicable - ACPI_NOT_PACKAGE_ELEMENT
0181  *                                otherwise)
0182  *
0183  * RETURN:      Status
0184  *
0185  * DESCRIPTION: Check the type of the return object against the expected object
0186  *              type(s). Use of Btype allows multiple expected object types.
0187  *
0188  ******************************************************************************/
0189
0190 acpi_status
0191 acpi_ns_check_object_type(struct acpi_evaluate_info *info,
0192               union acpi_operand_object **return_object_ptr,
0193               u32 expected_btypes, u32 package_index)
0194 {
0195     union acpi_operand_object *return_object = *return_object_ptr;
0196     acpi_status status = AE_OK;
0197     char type_buffer[96];   /* Room for 10 types */
0198
0199     /* A Namespace node should not get here, but make sure */
0200
0201     if (return_object &&
0202         ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
0203         ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
0204                       info->node_flags,
0205                       "Invalid return type - Found a Namespace node [%4.4s] type %s",
0206                       return_object->node.name.ascii,
0207                       acpi_ut_get_type_name(return_object->node.
0208                                 type)));
0209         return (AE_AML_OPERAND_TYPE);
0210     }
0211
0212     /*
0213      * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
0214      * The bitmapped type allows multiple possible return types.
0215      *
0216      * Note, the cases below must handle all of the possible types returned
0217      * from all of the predefined names (including elements of returned
0218      * packages)
0219      */
0220     info->return_btype = acpi_ns_get_bitmapped_type(return_object);
0221     if (info->return_btype == ACPI_RTYPE_ANY) {
0222
0223         /* Not one of the supported objects, must be incorrect */
0224         goto type_error_exit;
0225     }
0226
0227     /* For reference objects, check that the reference type is correct */
0228
0229     if ((info->return_btype & expected_btypes) == ACPI_RTYPE_REFERENCE) {
0230         status = acpi_ns_check_reference(info, return_object);
0231         return (status);
0232     }
0233
0234     /* Attempt simple repair of the returned object if necessary */
0235
0236     status = acpi_ns_simple_repair(info, expected_btypes,
0237                        package_index, return_object_ptr);
0238     if (ACPI_SUCCESS(status)) {
0239         return (AE_OK); /* Successful repair */
0240     }
0241
0242 type_error_exit:
0243
0244     /* Create a string with all expected types for this predefined object */
0245
0246     acpi_ut_get_expected_return_types(type_buffer, expected_btypes);
0247
0248     if (!return_object) {
0249         ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
0250                       info->node_flags,
0251                       "Expected return object of type %s",
0252                       type_buffer));
0253     } else if (package_index == ACPI_NOT_PACKAGE_ELEMENT) {
0254         ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
0255                       info->node_flags,
0256                       "Return type mismatch - found %s, expected %s",
0257                       acpi_ut_get_object_type_name
0258                       (return_object), type_buffer));
0259     } else {
0260         ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
0261                       info->node_flags,
0262                       "Return Package type mismatch at index %u - "
0263                       "found %s, expected %s", package_index,
0264                       acpi_ut_get_object_type_name
0265                       (return_object), type_buffer));
0266     }
0267
0268     return (AE_AML_OPERAND_TYPE);
0269 }
0270
0271 /*******************************************************************************
0272  *
0273  * FUNCTION:    acpi_ns_check_reference
0274  *
0275  * PARAMETERS:  info            - Method execution information block
0276  *              return_object   - Object returned from the evaluation of a
0277  *                                method or object
0278  *
0279  * RETURN:      Status
0280  *
0281  * DESCRIPTION: Check a returned reference object for the correct reference
0282  *              type. The only reference type that can be returned from a
0283  *              predefined method is a named reference. All others are invalid.
0284  *
0285  ******************************************************************************/
0286
0287 static acpi_status
0288 acpi_ns_check_reference(struct acpi_evaluate_info *info,
0289             union acpi_operand_object *return_object)
0290 {
0291
0292     /*
0293      * Check the reference object for the correct reference type (opcode).
0294      * The only type of reference that can be converted to a union acpi_object is
0295      * a reference to a named object (reference class: NAME)
0296      */
0297     if (return_object->reference.class == ACPI_REFCLASS_NAME) {
0298         return (AE_OK);
0299     }
0300
0301     ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname, info->node_flags,
0302                   "Return type mismatch - unexpected reference object type [%s] %2.2X",
0303                   acpi_ut_get_reference_name(return_object),
0304                   return_object->reference.class));
0305
0306     return (AE_AML_OPERAND_TYPE);
0307 }
0308
0309 /*******************************************************************************
0310  *
0311  * FUNCTION:    acpi_ns_get_bitmapped_type
0312  *
0313  * PARAMETERS:  return_object   - Object returned from method/obj evaluation
0314  *
0315  * RETURN:      Object return type. ACPI_RTYPE_ANY indicates that the object
0316  *              type is not supported. ACPI_RTYPE_NONE indicates that no
0317  *              object was returned (return_object is NULL).
0318  *
0319  * DESCRIPTION: Convert object type into a bitmapped object return type.
0320  *
0321  ******************************************************************************/
0322
0323 static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object)
0324 {
0325     u32 return_btype;
0326
0327     if (!return_object) {
0328         return (ACPI_RTYPE_NONE);
0329     }
0330
0331     /* Map acpi_object_type to internal bitmapped type */
0332
0333     switch (return_object->common.type) {
0334     case ACPI_TYPE_INTEGER:
0335
0336         return_btype = ACPI_RTYPE_INTEGER;
0337         break;
0338
0339     case ACPI_TYPE_BUFFER:
0340
0341         return_btype = ACPI_RTYPE_BUFFER;
0342         break;
0343
0344     case ACPI_TYPE_STRING:
0345
0346         return_btype = ACPI_RTYPE_STRING;
0347         break;
0348
0349     case ACPI_TYPE_PACKAGE:
0350
0351         return_btype = ACPI_RTYPE_PACKAGE;
0352         break;
0353
0354     case ACPI_TYPE_LOCAL_REFERENCE:
0355
0356         return_btype = ACPI_RTYPE_REFERENCE;
0357         break;
0358
0359     default:
0360
0361         /* Not one of the supported objects, must be incorrect */
0362
0363         return_btype = ACPI_RTYPE_ANY;
0364         break;
0365     }
0366
0367     return (return_btype);
0368 }