1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: nsarguments - Validation of args for ACPI predefined methods
5  *
6  * Copyright (C) 2000 - 2018, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acnamesp.h"
13 #include "acpredef.h"
14 
15 #define _COMPONENT          ACPI_NAMESPACE
16 ACPI_MODULE_NAME("nsarguments")
17 
18 /*******************************************************************************
19  *
20  * FUNCTION:    acpi_ns_check_argument_types
21  *
22  * PARAMETERS:  info            - Method execution information block
23  *
24  * RETURN:      None
25  *
26  * DESCRIPTION: Check the incoming argument count and all argument types
27  *              against the argument type list for a predefined name.
28  *
29  ******************************************************************************/
30 void acpi_ns_check_argument_types(struct acpi_evaluate_info *info)
31 {
32 	u16 arg_type_list;
33 	u8 arg_count;
34 	u8 arg_type;
35 	u8 user_arg_type;
36 	u32 i;
37 
38 	/*
39 	 * If not a predefined name, cannot typecheck args, because
40 	 * we have no idea what argument types are expected.
41 	 * Also, ignore typecheck if warnings/errors if this method
42 	 * has already been evaluated at least once -- in order
43 	 * to suppress repetitive messages.
44 	 */
45 	if (!info->predefined || (info->node->flags & ANOBJ_EVALUATED)) {
46 		return;
47 	}
48 
49 	arg_type_list = info->predefined->info.argument_list;
50 	arg_count = METHOD_GET_ARG_COUNT(arg_type_list);
51 
52 	/* Typecheck all arguments */
53 
54 	for (i = 0; ((i < arg_count) && (i < info->param_count)); i++) {
55 		arg_type = METHOD_GET_NEXT_TYPE(arg_type_list);
56 		user_arg_type = info->parameters[i]->common.type;
57 
58 		if (user_arg_type != arg_type) {
59 			ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
60 					      ACPI_WARN_ALWAYS,
61 					      "Argument #%u type mismatch - "
62 					      "Found [%s], ACPI requires [%s]",
63 					      (i + 1),
64 					      acpi_ut_get_type_name
65 					      (user_arg_type),
66 					      acpi_ut_get_type_name(arg_type)));
67 
68 			/* Prevent any additional typechecking for this method */
69 
70 			info->node->flags |= ANOBJ_EVALUATED;
71 		}
72 	}
73 }
74 
75 /*******************************************************************************
76  *
77  * FUNCTION:    acpi_ns_check_acpi_compliance
78  *
79  * PARAMETERS:  pathname        - Full pathname to the node (for error msgs)
80  *              node            - Namespace node for the method/object
81  *              predefined      - Pointer to entry in predefined name table
82  *
83  * RETURN:      None
84  *
85  * DESCRIPTION: Check that the declared parameter count (in ASL/AML) for a
86  *              predefined name is what is expected (matches what is defined in
87  *              the ACPI specification for this predefined name.)
88  *
89  ******************************************************************************/
90 
91 void
92 acpi_ns_check_acpi_compliance(char *pathname,
93 			      struct acpi_namespace_node *node,
94 			      const union acpi_predefined_info *predefined)
95 {
96 	u32 aml_param_count;
97 	u32 required_param_count;
98 
99 	if (!predefined || (node->flags & ANOBJ_EVALUATED)) {
100 		return;
101 	}
102 
103 	/* Get the ACPI-required arg count from the predefined info table */
104 
105 	required_param_count =
106 	    METHOD_GET_ARG_COUNT(predefined->info.argument_list);
107 
108 	/*
109 	 * If this object is not a control method, we can check if the ACPI
110 	 * spec requires that it be a method.
111 	 */
112 	if (node->type != ACPI_TYPE_METHOD) {
113 		if (required_param_count > 0) {
114 
115 			/* Object requires args, must be implemented as a method */
116 
117 			ACPI_BIOS_ERROR_PREDEFINED((AE_INFO, pathname,
118 						    ACPI_WARN_ALWAYS,
119 						    "Object (%s) must be a control method with %u arguments",
120 						    acpi_ut_get_type_name(node->
121 									  type),
122 						    required_param_count));
123 		} else if (!required_param_count
124 			   && !predefined->info.expected_btypes) {
125 
126 			/* Object requires no args and no return value, must be a method */
127 
128 			ACPI_BIOS_ERROR_PREDEFINED((AE_INFO, pathname,
129 						    ACPI_WARN_ALWAYS,
130 						    "Object (%s) must be a control method "
131 						    "with no arguments and no return value",
132 						    acpi_ut_get_type_name(node->
133 									  type)));
134 		}
135 
136 		return;
137 	}
138 
139 	/*
140 	 * This is a control method.
141 	 * Check that the ASL/AML-defined parameter count for this method
142 	 * matches the ACPI-required parameter count
143 	 *
144 	 * Some methods are allowed to have a "minimum" number of args (_SCP)
145 	 * because their definition in ACPI has changed over time.
146 	 *
147 	 * Note: These are BIOS errors in the declaration of the object
148 	 */
149 	aml_param_count = node->object->method.param_count;
150 
151 	if (aml_param_count < required_param_count) {
152 		ACPI_BIOS_ERROR_PREDEFINED((AE_INFO, pathname, ACPI_WARN_ALWAYS,
153 					    "Insufficient arguments - "
154 					    "ASL declared %u, ACPI requires %u",
155 					    aml_param_count,
156 					    required_param_count));
157 	} else if ((aml_param_count > required_param_count)
158 		   && !(predefined->info.
159 			argument_list & ARG_COUNT_IS_MINIMUM)) {
160 		ACPI_BIOS_ERROR_PREDEFINED((AE_INFO, pathname, ACPI_WARN_ALWAYS,
161 					    "Excess arguments - "
162 					    "ASL declared %u, ACPI requires %u",
163 					    aml_param_count,
164 					    required_param_count));
165 	}
166 }
167 
168 /*******************************************************************************
169  *
170  * FUNCTION:    acpi_ns_check_argument_count
171  *
172  * PARAMETERS:  pathname        - Full pathname to the node (for error msgs)
173  *              node            - Namespace node for the method/object
174  *              user_param_count - Number of args passed in by the caller
175  *              predefined      - Pointer to entry in predefined name table
176  *
177  * RETURN:      None
178  *
179  * DESCRIPTION: Check that incoming argument count matches the declared
180  *              parameter count (in the ASL/AML) for an object.
181  *
182  ******************************************************************************/
183 
184 void
185 acpi_ns_check_argument_count(char *pathname,
186 			     struct acpi_namespace_node *node,
187 			     u32 user_param_count,
188 			     const union acpi_predefined_info *predefined)
189 {
190 	u32 aml_param_count;
191 	u32 required_param_count;
192 
193 	if (node->flags & ANOBJ_EVALUATED) {
194 		return;
195 	}
196 
197 	if (!predefined) {
198 		/*
199 		 * Not a predefined name. Check the incoming user argument count
200 		 * against the count that is specified in the method/object.
201 		 */
202 		if (node->type != ACPI_TYPE_METHOD) {
203 			if (user_param_count) {
204 				ACPI_INFO_PREDEFINED((AE_INFO, pathname,
205 						      ACPI_WARN_ALWAYS,
206 						      "%u arguments were passed to a non-method ACPI object (%s)",
207 						      user_param_count,
208 						      acpi_ut_get_type_name
209 						      (node->type)));
210 			}
211 
212 			return;
213 		}
214 
215 		/*
216 		 * This is a control method. Check the parameter count.
217 		 * We can only check the incoming argument count against the
218 		 * argument count declared for the method in the ASL/AML.
219 		 *
220 		 * Emit a message if too few or too many arguments have been passed
221 		 * by the caller.
222 		 *
223 		 * Note: Too many arguments will not cause the method to
224 		 * fail. However, the method will fail if there are too few
225 		 * arguments and the method attempts to use one of the missing ones.
226 		 */
227 		aml_param_count = node->object->method.param_count;
228 
229 		if (user_param_count < aml_param_count) {
230 			ACPI_WARN_PREDEFINED((AE_INFO, pathname,
231 					      ACPI_WARN_ALWAYS,
232 					      "Insufficient arguments - "
233 					      "Caller passed %u, method requires %u",
234 					      user_param_count,
235 					      aml_param_count));
236 		} else if (user_param_count > aml_param_count) {
237 			ACPI_INFO_PREDEFINED((AE_INFO, pathname,
238 					      ACPI_WARN_ALWAYS,
239 					      "Excess arguments - "
240 					      "Caller passed %u, method requires %u",
241 					      user_param_count,
242 					      aml_param_count));
243 		}
244 
245 		return;
246 	}
247 
248 	/*
249 	 * This is a predefined name. Validate the user-supplied parameter
250 	 * count against the ACPI specification. We don't validate against
251 	 * the method itself because what is important here is that the
252 	 * caller is in conformance with the spec. (The arg count for the
253 	 * method was checked against the ACPI spec earlier.)
254 	 *
255 	 * Some methods are allowed to have a "minimum" number of args (_SCP)
256 	 * because their definition in ACPI has changed over time.
257 	 */
258 	required_param_count =
259 	    METHOD_GET_ARG_COUNT(predefined->info.argument_list);
260 
261 	if (user_param_count < required_param_count) {
262 		ACPI_WARN_PREDEFINED((AE_INFO, pathname, ACPI_WARN_ALWAYS,
263 				      "Insufficient arguments - "
264 				      "Caller passed %u, ACPI requires %u",
265 				      user_param_count, required_param_count));
266 	} else if ((user_param_count > required_param_count) &&
267 		   !(predefined->info.argument_list & ARG_COUNT_IS_MINIMUM)) {
268 		ACPI_INFO_PREDEFINED((AE_INFO, pathname, ACPI_WARN_ALWAYS,
269 				      "Excess arguments - "
270 				      "Caller passed %u, ACPI requires %u",
271 				      user_param_count, required_param_count));
272 	}
273 }
274