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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nsrepair.c (17407B)


      1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
      2/******************************************************************************
      3 *
      4 * Module Name: nsrepair - Repair for objects returned by predefined methods
      5 *
      6 * Copyright (C) 2000 - 2022, Intel Corp.
      7 *
      8 *****************************************************************************/
      9
     10#include <acpi/acpi.h>
     11#include "accommon.h"
     12#include "acnamesp.h"
     13#include "acinterp.h"
     14#include "acpredef.h"
     15#include "amlresrc.h"
     16
     17#define _COMPONENT          ACPI_NAMESPACE
     18ACPI_MODULE_NAME("nsrepair")
     19
     20/*******************************************************************************
     21 *
     22 * This module attempts to repair or convert objects returned by the
     23 * predefined methods to an object type that is expected, as per the ACPI
     24 * specification. The need for this code is dictated by the many machines that
     25 * return incorrect types for the standard predefined methods. Performing these
     26 * conversions here, in one place, eliminates the need for individual ACPI
     27 * device drivers to do the same. Note: Most of these conversions are different
     28 * than the internal object conversion routines used for implicit object
     29 * conversion.
     30 *
     31 * The following conversions can be performed as necessary:
     32 *
     33 * Integer -> String
     34 * Integer -> Buffer
     35 * String  -> Integer
     36 * String  -> Buffer
     37 * Buffer  -> Integer
     38 * Buffer  -> String
     39 * Buffer  -> Package of Integers
     40 * Package -> Package of one Package
     41 *
     42 * Additional conversions that are available:
     43 *  Convert a null return or zero return value to an end_tag descriptor
     44 *  Convert an ASCII string to a Unicode buffer
     45 *
     46 * An incorrect standalone object is wrapped with required outer package
     47 *
     48 * Additional possible repairs:
     49 * Required package elements that are NULL replaced by Integer/String/Buffer
     50 *
     51 ******************************************************************************/
     52/* Local prototypes */
     53static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
     54									 acpi_namespace_node
     55									 *node,
     56									 u32
     57									 return_btype,
     58									 u32
     59									 package_index);
     60
     61/*
     62 * Special but simple repairs for some names.
     63 *
     64 * 2nd argument: Unexpected types that can be repaired
     65 */
     66static const struct acpi_simple_repair_info acpi_object_repair_info[] = {
     67	/* Resource descriptor conversions */
     68
     69	{"_CRS",
     70	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
     71	 ACPI_RTYPE_NONE,
     72	 ACPI_NOT_PACKAGE_ELEMENT,
     73	 acpi_ns_convert_to_resource},
     74	{"_DMA",
     75	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
     76	 ACPI_RTYPE_NONE,
     77	 ACPI_NOT_PACKAGE_ELEMENT,
     78	 acpi_ns_convert_to_resource},
     79	{"_PRS",
     80	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
     81	 ACPI_RTYPE_NONE,
     82	 ACPI_NOT_PACKAGE_ELEMENT,
     83	 acpi_ns_convert_to_resource},
     84
     85	/* Object reference conversions */
     86
     87	{"_DEP", ACPI_RTYPE_STRING, ACPI_ALL_PACKAGE_ELEMENTS,
     88	 acpi_ns_convert_to_reference},
     89
     90	/* Unicode conversions */
     91
     92	{"_MLS", ACPI_RTYPE_STRING, 1,
     93	 acpi_ns_convert_to_unicode},
     94	{"_STR", ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER,
     95	 ACPI_NOT_PACKAGE_ELEMENT,
     96	 acpi_ns_convert_to_unicode},
     97	{{0, 0, 0, 0}, 0, 0, NULL}	/* Table terminator */
     98};
     99
    100/*******************************************************************************
    101 *
    102 * FUNCTION:    acpi_ns_simple_repair
    103 *
    104 * PARAMETERS:  info                - Method execution information block
    105 *              expected_btypes     - Object types expected
    106 *              package_index       - Index of object within parent package (if
    107 *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
    108 *                                    otherwise)
    109 *              return_object_ptr   - Pointer to the object returned from the
    110 *                                    evaluation of a method or object
    111 *
    112 * RETURN:      Status. AE_OK if repair was successful.
    113 *
    114 * DESCRIPTION: Attempt to repair/convert a return object of a type that was
    115 *              not expected.
    116 *
    117 ******************************************************************************/
    118
    119acpi_status
    120acpi_ns_simple_repair(struct acpi_evaluate_info *info,
    121		      u32 expected_btypes,
    122		      u32 package_index,
    123		      union acpi_operand_object **return_object_ptr)
    124{
    125	union acpi_operand_object *return_object = *return_object_ptr;
    126	union acpi_operand_object *new_object = NULL;
    127	acpi_status status;
    128	const struct acpi_simple_repair_info *predefined;
    129
    130	ACPI_FUNCTION_NAME(ns_simple_repair);
    131
    132	/*
    133	 * Special repairs for certain names that are in the repair table.
    134	 * Check if this name is in the list of repairable names.
    135	 */
    136	predefined = acpi_ns_match_simple_repair(info->node,
    137						 info->return_btype,
    138						 package_index);
    139	if (predefined) {
    140		if (!return_object) {
    141			ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
    142					      ACPI_WARN_ALWAYS,
    143					      "Missing expected return value"));
    144		}
    145
    146		status = predefined->object_converter(info->node, return_object,
    147						      &new_object);
    148		if (ACPI_FAILURE(status)) {
    149
    150			/* A fatal error occurred during a conversion */
    151
    152			ACPI_EXCEPTION((AE_INFO, status,
    153					"During return object analysis"));
    154			return (status);
    155		}
    156		if (new_object) {
    157			goto object_repaired;
    158		}
    159	}
    160
    161	/*
    162	 * Do not perform simple object repair unless the return type is not
    163	 * expected.
    164	 */
    165	if (info->return_btype & expected_btypes) {
    166		return (AE_OK);
    167	}
    168
    169	/*
    170	 * At this point, we know that the type of the returned object was not
    171	 * one of the expected types for this predefined name. Attempt to
    172	 * repair the object by converting it to one of the expected object
    173	 * types for this predefined name.
    174	 */
    175
    176	/*
    177	 * If there is no return value, check if we require a return value for
    178	 * this predefined name. Either one return value is expected, or none,
    179	 * for both methods and other objects.
    180	 *
    181	 * Try to fix if there was no return object. Warning if failed to fix.
    182	 */
    183	if (!return_object) {
    184		if (expected_btypes && (!(expected_btypes & ACPI_RTYPE_NONE))) {
    185			if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
    186				ACPI_WARN_PREDEFINED((AE_INFO,
    187						      info->full_pathname,
    188						      ACPI_WARN_ALWAYS,
    189						      "Found unexpected NULL package element"));
    190
    191				status =
    192				    acpi_ns_repair_null_element(info,
    193								expected_btypes,
    194								package_index,
    195								return_object_ptr);
    196				if (ACPI_SUCCESS(status)) {
    197					return (AE_OK);	/* Repair was successful */
    198				}
    199			} else {
    200				ACPI_WARN_PREDEFINED((AE_INFO,
    201						      info->full_pathname,
    202						      ACPI_WARN_ALWAYS,
    203						      "Missing expected return value"));
    204			}
    205
    206			return (AE_AML_NO_RETURN_VALUE);
    207		}
    208	}
    209
    210	if (expected_btypes & ACPI_RTYPE_INTEGER) {
    211		status = acpi_ns_convert_to_integer(return_object, &new_object);
    212		if (ACPI_SUCCESS(status)) {
    213			goto object_repaired;
    214		}
    215	}
    216	if (expected_btypes & ACPI_RTYPE_STRING) {
    217		status = acpi_ns_convert_to_string(return_object, &new_object);
    218		if (ACPI_SUCCESS(status)) {
    219			goto object_repaired;
    220		}
    221	}
    222	if (expected_btypes & ACPI_RTYPE_BUFFER) {
    223		status = acpi_ns_convert_to_buffer(return_object, &new_object);
    224		if (ACPI_SUCCESS(status)) {
    225			goto object_repaired;
    226		}
    227	}
    228	if (expected_btypes & ACPI_RTYPE_PACKAGE) {
    229		/*
    230		 * A package is expected. We will wrap the existing object with a
    231		 * new package object. It is often the case that if a variable-length
    232		 * package is required, but there is only a single object needed, the
    233		 * BIOS will return that object instead of wrapping it with a Package
    234		 * object. Note: after the wrapping, the package will be validated
    235		 * for correct contents (expected object type or types).
    236		 */
    237		status =
    238		    acpi_ns_wrap_with_package(info, return_object, &new_object);
    239		if (ACPI_SUCCESS(status)) {
    240			/*
    241			 * The original object just had its reference count
    242			 * incremented for being inserted into the new package.
    243			 */
    244			*return_object_ptr = new_object;	/* New Package object */
    245			info->return_flags |= ACPI_OBJECT_REPAIRED;
    246			return (AE_OK);
    247		}
    248	}
    249
    250	/* We cannot repair this object */
    251
    252	return (AE_AML_OPERAND_TYPE);
    253
    254object_repaired:
    255
    256	/* Object was successfully repaired */
    257
    258	if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
    259
    260		/* Update reference count of new object */
    261
    262		if (!(info->return_flags & ACPI_OBJECT_WRAPPED)) {
    263			new_object->common.reference_count =
    264			    return_object->common.reference_count;
    265		}
    266
    267		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
    268				  "%s: Converted %s to expected %s at Package index %u\n",
    269				  info->full_pathname,
    270				  acpi_ut_get_object_type_name(return_object),
    271				  acpi_ut_get_object_type_name(new_object),
    272				  package_index));
    273	} else {
    274		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
    275				  "%s: Converted %s to expected %s\n",
    276				  info->full_pathname,
    277				  acpi_ut_get_object_type_name(return_object),
    278				  acpi_ut_get_object_type_name(new_object)));
    279	}
    280
    281	/* Delete old object, install the new return object */
    282
    283	acpi_ut_remove_reference(return_object);
    284	*return_object_ptr = new_object;
    285	info->return_flags |= ACPI_OBJECT_REPAIRED;
    286	return (AE_OK);
    287}
    288
    289/******************************************************************************
    290 *
    291 * FUNCTION:    acpi_ns_match_simple_repair
    292 *
    293 * PARAMETERS:  node                - Namespace node for the method/object
    294 *              return_btype        - Object type that was returned
    295 *              package_index       - Index of object within parent package (if
    296 *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
    297 *                                    otherwise)
    298 *
    299 * RETURN:      Pointer to entry in repair table. NULL indicates not found.
    300 *
    301 * DESCRIPTION: Check an object name against the repairable object list.
    302 *
    303 *****************************************************************************/
    304
    305static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
    306									 acpi_namespace_node
    307									 *node,
    308									 u32
    309									 return_btype,
    310									 u32
    311									 package_index)
    312{
    313	const struct acpi_simple_repair_info *this_name;
    314
    315	/* Search info table for a repairable predefined method/object name */
    316
    317	this_name = acpi_object_repair_info;
    318	while (this_name->object_converter) {
    319		if (ACPI_COMPARE_NAMESEG(node->name.ascii, this_name->name)) {
    320
    321			/* Check if we can actually repair this name/type combination */
    322
    323			if ((return_btype & this_name->unexpected_btypes) &&
    324			    (this_name->package_index ==
    325			     ACPI_ALL_PACKAGE_ELEMENTS
    326			     || package_index == this_name->package_index)) {
    327				return (this_name);
    328			}
    329
    330			return (NULL);
    331		}
    332
    333		this_name++;
    334	}
    335
    336	return (NULL);		/* Name was not found in the repair table */
    337}
    338
    339/*******************************************************************************
    340 *
    341 * FUNCTION:    acpi_ns_repair_null_element
    342 *
    343 * PARAMETERS:  info                - Method execution information block
    344 *              expected_btypes     - Object types expected
    345 *              package_index       - Index of object within parent package (if
    346 *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
    347 *                                    otherwise)
    348 *              return_object_ptr   - Pointer to the object returned from the
    349 *                                    evaluation of a method or object
    350 *
    351 * RETURN:      Status. AE_OK if repair was successful.
    352 *
    353 * DESCRIPTION: Attempt to repair a NULL element of a returned Package object.
    354 *
    355 ******************************************************************************/
    356
    357acpi_status
    358acpi_ns_repair_null_element(struct acpi_evaluate_info *info,
    359			    u32 expected_btypes,
    360			    u32 package_index,
    361			    union acpi_operand_object **return_object_ptr)
    362{
    363	union acpi_operand_object *return_object = *return_object_ptr;
    364	union acpi_operand_object *new_object;
    365
    366	ACPI_FUNCTION_NAME(ns_repair_null_element);
    367
    368	/* No repair needed if return object is non-NULL */
    369
    370	if (return_object) {
    371		return (AE_OK);
    372	}
    373
    374	/*
    375	 * Attempt to repair a NULL element of a Package object. This applies to
    376	 * predefined names that return a fixed-length package and each element
    377	 * is required. It does not apply to variable-length packages where NULL
    378	 * elements are allowed, especially at the end of the package.
    379	 */
    380	if (expected_btypes & ACPI_RTYPE_INTEGER) {
    381
    382		/* Need an integer - create a zero-value integer */
    383
    384		new_object = acpi_ut_create_integer_object((u64)0);
    385	} else if (expected_btypes & ACPI_RTYPE_STRING) {
    386
    387		/* Need a string - create a NULL string */
    388
    389		new_object = acpi_ut_create_string_object(0);
    390	} else if (expected_btypes & ACPI_RTYPE_BUFFER) {
    391
    392		/* Need a buffer - create a zero-length buffer */
    393
    394		new_object = acpi_ut_create_buffer_object(0);
    395	} else {
    396		/* Error for all other expected types */
    397
    398		return (AE_AML_OPERAND_TYPE);
    399	}
    400
    401	if (!new_object) {
    402		return (AE_NO_MEMORY);
    403	}
    404
    405	/* Set the reference count according to the parent Package object */
    406
    407	new_object->common.reference_count =
    408	    info->parent_package->common.reference_count;
    409
    410	ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
    411			  "%s: Converted NULL package element to expected %s at index %u\n",
    412			  info->full_pathname,
    413			  acpi_ut_get_object_type_name(new_object),
    414			  package_index));
    415
    416	*return_object_ptr = new_object;
    417	info->return_flags |= ACPI_OBJECT_REPAIRED;
    418	return (AE_OK);
    419}
    420
    421/******************************************************************************
    422 *
    423 * FUNCTION:    acpi_ns_remove_null_elements
    424 *
    425 * PARAMETERS:  info                - Method execution information block
    426 *              package_type        - An acpi_return_package_types value
    427 *              obj_desc            - A Package object
    428 *
    429 * RETURN:      None.
    430 *
    431 * DESCRIPTION: Remove all NULL package elements from packages that contain
    432 *              a variable number of subpackages. For these types of
    433 *              packages, NULL elements can be safely removed.
    434 *
    435 *****************************************************************************/
    436
    437void
    438acpi_ns_remove_null_elements(struct acpi_evaluate_info *info,
    439			     u8 package_type,
    440			     union acpi_operand_object *obj_desc)
    441{
    442	union acpi_operand_object **source;
    443	union acpi_operand_object **dest;
    444	u32 count;
    445	u32 new_count;
    446	u32 i;
    447
    448	ACPI_FUNCTION_NAME(ns_remove_null_elements);
    449
    450	/*
    451	 * We can safely remove all NULL elements from these package types:
    452	 * PTYPE1_VAR packages contain a variable number of simple data types.
    453	 * PTYPE2 packages contain a variable number of subpackages.
    454	 */
    455	switch (package_type) {
    456	case ACPI_PTYPE1_VAR:
    457	case ACPI_PTYPE2:
    458	case ACPI_PTYPE2_COUNT:
    459	case ACPI_PTYPE2_PKG_COUNT:
    460	case ACPI_PTYPE2_FIXED:
    461	case ACPI_PTYPE2_MIN:
    462	case ACPI_PTYPE2_REV_FIXED:
    463	case ACPI_PTYPE2_FIX_VAR:
    464		break;
    465
    466	default:
    467	case ACPI_PTYPE2_VAR_VAR:
    468	case ACPI_PTYPE1_FIXED:
    469	case ACPI_PTYPE1_OPTION:
    470		return;
    471	}
    472
    473	count = obj_desc->package.count;
    474	new_count = count;
    475
    476	source = obj_desc->package.elements;
    477	dest = source;
    478
    479	/* Examine all elements of the package object, remove nulls */
    480
    481	for (i = 0; i < count; i++) {
    482		if (!*source) {
    483			new_count--;
    484		} else {
    485			*dest = *source;
    486			dest++;
    487		}
    488
    489		source++;
    490	}
    491
    492	/* Update parent package if any null elements were removed */
    493
    494	if (new_count < count) {
    495		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
    496				  "%s: Found and removed %u NULL elements\n",
    497				  info->full_pathname, (count - new_count)));
    498
    499		/* NULL terminate list and update the package count */
    500
    501		*dest = NULL;
    502		obj_desc->package.count = new_count;
    503	}
    504}
    505
    506/*******************************************************************************
    507 *
    508 * FUNCTION:    acpi_ns_wrap_with_package
    509 *
    510 * PARAMETERS:  info                - Method execution information block
    511 *              original_object     - Pointer to the object to repair.
    512 *              obj_desc_ptr        - The new package object is returned here
    513 *
    514 * RETURN:      Status, new object in *obj_desc_ptr
    515 *
    516 * DESCRIPTION: Repair a common problem with objects that are defined to
    517 *              return a variable-length Package of sub-objects. If there is
    518 *              only one sub-object, some BIOS code mistakenly simply declares
    519 *              the single object instead of a Package with one sub-object.
    520 *              This function attempts to repair this error by wrapping a
    521 *              Package object around the original object, creating the
    522 *              correct and expected Package with one sub-object.
    523 *
    524 *              Names that can be repaired in this manner include:
    525 *              _ALR, _CSD, _HPX, _MLS, _PLD, _PRT, _PSS, _TRT, _TSS,
    526 *              _BCL, _DOD, _FIX, _Sx
    527 *
    528 ******************************************************************************/
    529
    530acpi_status
    531acpi_ns_wrap_with_package(struct acpi_evaluate_info *info,
    532			  union acpi_operand_object *original_object,
    533			  union acpi_operand_object **obj_desc_ptr)
    534{
    535	union acpi_operand_object *pkg_obj_desc;
    536
    537	ACPI_FUNCTION_NAME(ns_wrap_with_package);
    538
    539	/*
    540	 * Create the new outer package and populate it. The new
    541	 * package will have a single element, the lone sub-object.
    542	 */
    543	pkg_obj_desc = acpi_ut_create_package_object(1);
    544	if (!pkg_obj_desc) {
    545		return (AE_NO_MEMORY);
    546	}
    547
    548	pkg_obj_desc->package.elements[0] = original_object;
    549
    550	ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
    551			  "%s: Wrapped %s with expected Package object\n",
    552			  info->full_pathname,
    553			  acpi_ut_get_object_type_name(original_object)));
    554
    555	/* Return the new object in the object pointer */
    556
    557	*obj_desc_ptr = pkg_obj_desc;
    558	info->return_flags |= ACPI_OBJECT_REPAIRED | ACPI_OBJECT_WRAPPED;
    559	return (AE_OK);
    560}