cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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nspredef.c (11878B)


      1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
      2/******************************************************************************
      3 *
      4 * Module Name: nspredef - Validation of ACPI predefined methods and objects
      5 *
      6 * Copyright (C) 2000 - 2022, Intel Corp.
      7 *
      8 *****************************************************************************/
      9
     10#define ACPI_CREATE_PREDEFINED_TABLE
     11
     12#include <acpi/acpi.h>
     13#include "accommon.h"
     14#include "acnamesp.h"
     15#include "acpredef.h"
     16
     17#define _COMPONENT          ACPI_NAMESPACE
     18ACPI_MODULE_NAME("nspredef")
     19
     20/*******************************************************************************
     21 *
     22 * This module validates predefined ACPI objects that appear in the namespace,
     23 * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
     24 * validation is to detect problems with BIOS-exposed predefined ACPI objects
     25 * before the results are returned to the ACPI-related drivers.
     26 *
     27 * There are several areas that are validated:
     28 *
     29 *  1) The number of input arguments as defined by the method/object in the
     30 *     ASL is validated against the ACPI specification.
     31 *  2) The type of the return object (if any) is validated against the ACPI
     32 *     specification.
     33 *  3) For returned package objects, the count of package elements is
     34 *     validated, as well as the type of each package element. Nested
     35 *     packages are supported.
     36 *
     37 * For any problems found, a warning message is issued.
     38 *
     39 ******************************************************************************/
     40/* Local prototypes */
     41static acpi_status
     42acpi_ns_check_reference(struct acpi_evaluate_info *info,
     43			union acpi_operand_object *return_object);
     44
     45static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object);
     46
     47/*******************************************************************************
     48 *
     49 * FUNCTION:    acpi_ns_check_return_value
     50 *
     51 * PARAMETERS:  node            - Namespace node for the method/object
     52 *              info            - Method execution information block
     53 *              user_param_count - Number of parameters actually passed
     54 *              return_status   - Status from the object evaluation
     55 *              return_object_ptr - Pointer to the object returned from the
     56 *                                evaluation of a method or object
     57 *
     58 * RETURN:      Status
     59 *
     60 * DESCRIPTION: Check the value returned from a predefined name.
     61 *
     62 ******************************************************************************/
     63
     64acpi_status
     65acpi_ns_check_return_value(struct acpi_namespace_node *node,
     66			   struct acpi_evaluate_info *info,
     67			   u32 user_param_count,
     68			   acpi_status return_status,
     69			   union acpi_operand_object **return_object_ptr)
     70{
     71	acpi_status status;
     72	const union acpi_predefined_info *predefined;
     73
     74	ACPI_FUNCTION_TRACE(ns_check_return_value);
     75
     76	/* If not a predefined name, we cannot validate the return object */
     77
     78	predefined = info->predefined;
     79	if (!predefined) {
     80		return_ACPI_STATUS(AE_OK);
     81	}
     82
     83	/*
     84	 * If the method failed or did not actually return an object, we cannot
     85	 * validate the return object
     86	 */
     87	if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
     88		return_ACPI_STATUS(AE_OK);
     89	}
     90
     91	/*
     92	 * Return value validation and possible repair.
     93	 *
     94	 * 1) Don't perform return value validation/repair if this feature
     95	 * has been disabled via a global option.
     96	 *
     97	 * 2) We have a return value, but if one wasn't expected, just exit,
     98	 * this is not a problem. For example, if the "Implicit Return"
     99	 * feature is enabled, methods will always return a value.
    100	 *
    101	 * 3) If the return value can be of any type, then we cannot perform
    102	 * any validation, just exit.
    103	 */
    104	if (acpi_gbl_disable_auto_repair ||
    105	    (!predefined->info.expected_btypes) ||
    106	    (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
    107		return_ACPI_STATUS(AE_OK);
    108	}
    109
    110	/*
    111	 * Check that the type of the main return object is what is expected
    112	 * for this predefined name
    113	 */
    114	status = acpi_ns_check_object_type(info, return_object_ptr,
    115					   predefined->info.expected_btypes,
    116					   ACPI_NOT_PACKAGE_ELEMENT);
    117	if (ACPI_FAILURE(status)) {
    118		goto exit;
    119	}
    120
    121	/*
    122	 *
    123	 * 4) If there is no return value and it is optional, just return
    124	 * AE_OK (_WAK).
    125	 */
    126	if (!(*return_object_ptr)) {
    127		goto exit;
    128	}
    129
    130	/*
    131	 * For returned Package objects, check the type of all sub-objects.
    132	 * Note: Package may have been newly created by call above.
    133	 */
    134	if ((*return_object_ptr)->common.type == ACPI_TYPE_PACKAGE) {
    135		info->parent_package = *return_object_ptr;
    136		status = acpi_ns_check_package(info, return_object_ptr);
    137		if (ACPI_FAILURE(status)) {
    138
    139			/* We might be able to fix some errors */
    140
    141			if ((status != AE_AML_OPERAND_TYPE) &&
    142			    (status != AE_AML_OPERAND_VALUE)) {
    143				goto exit;
    144			}
    145		}
    146	}
    147
    148	/*
    149	 * The return object was OK, or it was successfully repaired above.
    150	 * Now make some additional checks such as verifying that package
    151	 * objects are sorted correctly (if required) or buffer objects have
    152	 * the correct data width (bytes vs. dwords). These repairs are
    153	 * performed on a per-name basis, i.e., the code is specific to
    154	 * particular predefined names.
    155	 */
    156	status = acpi_ns_complex_repairs(info, node, status, return_object_ptr);
    157
    158exit:
    159	/*
    160	 * If the object validation failed or if we successfully repaired one
    161	 * or more objects, mark the parent node to suppress further warning
    162	 * messages during the next evaluation of the same method/object.
    163	 */
    164	if (ACPI_FAILURE(status) || (info->return_flags & ACPI_OBJECT_REPAIRED)) {
    165		node->flags |= ANOBJ_EVALUATED;
    166	}
    167
    168	return_ACPI_STATUS(status);
    169}
    170
    171/*******************************************************************************
    172 *
    173 * FUNCTION:    acpi_ns_check_object_type
    174 *
    175 * PARAMETERS:  info            - Method execution information block
    176 *              return_object_ptr - Pointer to the object returned from the
    177 *                                evaluation of a method or object
    178 *              expected_btypes - Bitmap of expected return type(s)
    179 *              package_index   - Index of object within parent package (if
    180 *                                applicable - ACPI_NOT_PACKAGE_ELEMENT
    181 *                                otherwise)
    182 *
    183 * RETURN:      Status
    184 *
    185 * DESCRIPTION: Check the type of the return object against the expected object
    186 *              type(s). Use of Btype allows multiple expected object types.
    187 *
    188 ******************************************************************************/
    189
    190acpi_status
    191acpi_ns_check_object_type(struct acpi_evaluate_info *info,
    192			  union acpi_operand_object **return_object_ptr,
    193			  u32 expected_btypes, u32 package_index)
    194{
    195	union acpi_operand_object *return_object = *return_object_ptr;
    196	acpi_status status = AE_OK;
    197	char type_buffer[96];	/* Room for 10 types */
    198
    199	/* A Namespace node should not get here, but make sure */
    200
    201	if (return_object &&
    202	    ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
    203		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
    204				      info->node_flags,
    205				      "Invalid return type - Found a Namespace node [%4.4s] type %s",
    206				      return_object->node.name.ascii,
    207				      acpi_ut_get_type_name(return_object->node.
    208							    type)));
    209		return (AE_AML_OPERAND_TYPE);
    210	}
    211
    212	/*
    213	 * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
    214	 * The bitmapped type allows multiple possible return types.
    215	 *
    216	 * Note, the cases below must handle all of the possible types returned
    217	 * from all of the predefined names (including elements of returned
    218	 * packages)
    219	 */
    220	info->return_btype = acpi_ns_get_bitmapped_type(return_object);
    221	if (info->return_btype == ACPI_RTYPE_ANY) {
    222
    223		/* Not one of the supported objects, must be incorrect */
    224		goto type_error_exit;
    225	}
    226
    227	/* For reference objects, check that the reference type is correct */
    228
    229	if ((info->return_btype & expected_btypes) == ACPI_RTYPE_REFERENCE) {
    230		status = acpi_ns_check_reference(info, return_object);
    231		return (status);
    232	}
    233
    234	/* Attempt simple repair of the returned object if necessary */
    235
    236	status = acpi_ns_simple_repair(info, expected_btypes,
    237				       package_index, return_object_ptr);
    238	if (ACPI_SUCCESS(status)) {
    239		return (AE_OK);	/* Successful repair */
    240	}
    241
    242type_error_exit:
    243
    244	/* Create a string with all expected types for this predefined object */
    245
    246	acpi_ut_get_expected_return_types(type_buffer, expected_btypes);
    247
    248	if (!return_object) {
    249		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
    250				      info->node_flags,
    251				      "Expected return object of type %s",
    252				      type_buffer));
    253	} else if (package_index == ACPI_NOT_PACKAGE_ELEMENT) {
    254		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
    255				      info->node_flags,
    256				      "Return type mismatch - found %s, expected %s",
    257				      acpi_ut_get_object_type_name
    258				      (return_object), type_buffer));
    259	} else {
    260		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
    261				      info->node_flags,
    262				      "Return Package type mismatch at index %u - "
    263				      "found %s, expected %s", package_index,
    264				      acpi_ut_get_object_type_name
    265				      (return_object), type_buffer));
    266	}
    267
    268	return (AE_AML_OPERAND_TYPE);
    269}
    270
    271/*******************************************************************************
    272 *
    273 * FUNCTION:    acpi_ns_check_reference
    274 *
    275 * PARAMETERS:  info            - Method execution information block
    276 *              return_object   - Object returned from the evaluation of a
    277 *                                method or object
    278 *
    279 * RETURN:      Status
    280 *
    281 * DESCRIPTION: Check a returned reference object for the correct reference
    282 *              type. The only reference type that can be returned from a
    283 *              predefined method is a named reference. All others are invalid.
    284 *
    285 ******************************************************************************/
    286
    287static acpi_status
    288acpi_ns_check_reference(struct acpi_evaluate_info *info,
    289			union acpi_operand_object *return_object)
    290{
    291
    292	/*
    293	 * Check the reference object for the correct reference type (opcode).
    294	 * The only type of reference that can be converted to a union acpi_object is
    295	 * a reference to a named object (reference class: NAME)
    296	 */
    297	if (return_object->reference.class == ACPI_REFCLASS_NAME) {
    298		return (AE_OK);
    299	}
    300
    301	ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname, info->node_flags,
    302			      "Return type mismatch - unexpected reference object type [%s] %2.2X",
    303			      acpi_ut_get_reference_name(return_object),
    304			      return_object->reference.class));
    305
    306	return (AE_AML_OPERAND_TYPE);
    307}
    308
    309/*******************************************************************************
    310 *
    311 * FUNCTION:    acpi_ns_get_bitmapped_type
    312 *
    313 * PARAMETERS:  return_object   - Object returned from method/obj evaluation
    314 *
    315 * RETURN:      Object return type. ACPI_RTYPE_ANY indicates that the object
    316 *              type is not supported. ACPI_RTYPE_NONE indicates that no
    317 *              object was returned (return_object is NULL).
    318 *
    319 * DESCRIPTION: Convert object type into a bitmapped object return type.
    320 *
    321 ******************************************************************************/
    322
    323static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object)
    324{
    325	u32 return_btype;
    326
    327	if (!return_object) {
    328		return (ACPI_RTYPE_NONE);
    329	}
    330
    331	/* Map acpi_object_type to internal bitmapped type */
    332
    333	switch (return_object->common.type) {
    334	case ACPI_TYPE_INTEGER:
    335
    336		return_btype = ACPI_RTYPE_INTEGER;
    337		break;
    338
    339	case ACPI_TYPE_BUFFER:
    340
    341		return_btype = ACPI_RTYPE_BUFFER;
    342		break;
    343
    344	case ACPI_TYPE_STRING:
    345
    346		return_btype = ACPI_RTYPE_STRING;
    347		break;
    348
    349	case ACPI_TYPE_PACKAGE:
    350
    351		return_btype = ACPI_RTYPE_PACKAGE;
    352		break;
    353
    354	case ACPI_TYPE_LOCAL_REFERENCE:
    355
    356		return_btype = ACPI_RTYPE_REFERENCE;
    357		break;
    358
    359	default:
    360
    361		/* Not one of the supported objects, must be incorrect */
    362
    363		return_btype = ACPI_RTYPE_ANY;
    364		break;
    365	}
    366
    367	return (return_btype);
    368}