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 - 2023, 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 expected_btypes: 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, validate_status: 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(buffer: 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}
369

source code of linux/drivers/acpi/acpica/nspredef.c