ACPICA: New: Validation for predefined ACPI methods/objects

Validates predefined ACPI objects that appear in the namespace,
at the time they are evaluated. The argument count and the type of
the returned object are validated. The purpose of this validation
is to detect problems with the BIOS-exposed predefined ACPI objects
before the results are returned to the ACPI-related drivers.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/acpi/namespace/Makefile

@@ -5,7 +5,7 @@
 obj-y := nsaccess.o  nsload.o    nssearch.o  nsxfeval.o \
 	 nsalloc.o   nseval.o    nsnames.o   nsutils.o   nsxfname.o \
 	 nsdump.o    nsinit.o    nsobject.o  nswalk.o    nsxfobj.o  \
-	 nsparse.o
+	 nsparse.o   nspredef.o
 
 obj-$(ACPI_FUTURE_USAGE) += nsdumpdv.o
 

drivers/acpi/namespace/nseval.c

@@ -78,6 +78,7 @@ ACPI_MODULE_NAME("nseval")
 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
 {
 	acpi_status status;
+	struct acpi_namespace_node *node;
 
 	ACPI_FUNCTION_TRACE(ns_evaluate);
 
@@ -117,6 +118,8 @@ acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
 			  info->resolved_node,
 			  acpi_ns_get_attached_object(info->resolved_node)));
 
+	node = info->resolved_node;
+
 	/*
 	 * Two major cases here:
 	 *
@@ -261,9 +264,35 @@ acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
 		}
 	}
 
-	/*
-	 * Check if there is a return value that must be dealt with
-	 */
+	/* Validation of return values for ACPI-predefined methods and objects */
+
+	if ((status == AE_OK) || (status == AE_CTRL_RETURN_VALUE)) {
+		/*
+		 * If this is the first evaluation, check the return value. This
+		 * ensures that any warnings will only be emitted during the very
+		 * first evaluation of the object.
+		 */
+		if (!(node->flags & ANOBJ_EVALUATED)) {
+			/*
+			 * Check for a predefined ACPI name. If found, validate the
+			 * returned object.
+			 *
+			 * Note: Ignore return status for now, emit warnings if there are
+			 * problems with the returned object. May change later to abort
+			 * the method on invalid return object.
+			 */
+			(void)acpi_ns_check_predefined_names(node,
+							     info->
+							     return_object);
+		}
+
+		/* Mark the node as having been evaluated */
+
+		node->flags |= ANOBJ_EVALUATED;
+	}
+
+	/* Check if there is a return value that must be dealt with */
+
 	if (status == AE_CTRL_RETURN_VALUE) {
 
 		/* If caller does not want the return value, delete it */

drivers/acpi/namespace/nsnames.c

@@ -115,7 +115,6 @@ acpi_ns_build_external_path(struct acpi_namespace_node *node,
 	return (AE_OK);
 }
 
-#ifdef ACPI_DEBUG_OUTPUT
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ns_get_external_pathname
@@ -163,7 +162,6 @@ char *acpi_ns_get_external_pathname(struct acpi_namespace_node *node)
 
 	return_PTR(name_buffer);
 }
-#endif
 
 /*******************************************************************************
  *

include/acpi/acdebug.h

@@ -154,6 +154,10 @@ void
 acpi_db_display_argument_object(union acpi_operand_object *obj_desc,
 				struct acpi_walk_state *walk_state);
 
+void acpi_db_check_predefined_names(void);
+
+void acpi_db_batch_execute(void);
+
 /*
  * dbexec - debugger control method execution
  */

include/acpi/aclocal.h

@@ -208,6 +208,7 @@ struct acpi_namespace_node {
 #define ANOBJ_METHOD_ARG                0x04	/* Node is a method argument */
 #define ANOBJ_METHOD_LOCAL              0x08	/* Node is a method local */
 #define ANOBJ_SUBTREE_HAS_INI           0x10	/* Used to optimize device initialization */
+#define ANOBJ_EVALUATED                 0x20	/* Set on first evaluation of node */
 
 #define ANOBJ_IS_EXTERNAL               0x08	/* i_aSL only: This object created via External() */
 #define ANOBJ_METHOD_NO_RETVAL          0x10	/* i_aSL only: Method has no return value */
@@ -340,6 +341,82 @@ acpi_status(*ACPI_INTERNAL_METHOD) (struct acpi_walk_state * walk_state);
 #define ACPI_BTYPE_OBJECTS_AND_REFS     0x0001FFFF	/* ARG or LOCAL */
 #define ACPI_BTYPE_ALL_OBJECTS          0x0000FFFF
 
+/*
+ * Information structure for ACPI predefined names.
+ * Each entry in the table contains the following items:
+ *
+ * Name                 - The ACPI reserved name
+ * param_count          - Number of arguments to the method
+ * expected_return_btypes - Allowed type(s) for the return value
+ */
+struct acpi_name_info {
+	char name[ACPI_NAME_SIZE];
+	u8 param_count;
+	u8 expected_btypes;
+};
+
+/*
+ * Secondary information structures for ACPI predefined objects that return
+ * package objects. This structure appears as the next entry in the table
+ * after the NAME_INFO structure above.
+ *
+ * The reason for this is to minimize the size of the predefined name table.
+ */
+
+/*
+ * Used for ACPI_PTYPE1_FIXED, ACPI_PTYPE1_VAR, ACPI_PTYPE2,
+ * ACPI_PTYPE2_MIN, ACPI_PTYPE2_PKG_COUNT, ACPI_PTYPE2_COUNT
+ */
+struct acpi_package_info {
+	u8 type;
+	u8 object_type1;
+	u8 count1;
+	u8 object_type2;
+	u8 count2;
+	u8 reserved;
+};
+
+/* Used for ACPI_PTYPE2_FIXED */
+
+struct acpi_package_info2 {
+	u8 type;
+	u8 count;
+	u8 object_type[4];
+};
+
+/* Used for ACPI_PTYPE1_OPTION */
+
+struct acpi_package_info3 {
+	u8 type;
+	u8 count;
+	u8 object_type[2];
+	u8 tail_object_type;
+	u8 reserved;
+};
+
+union acpi_predefined_info {
+	struct acpi_name_info info;
+	struct acpi_package_info ret_info;
+	struct acpi_package_info2 ret_info2;
+	struct acpi_package_info3 ret_info3;
+};
+
+/*
+ * Bitmapped return value types
+ * Note: the actual data types must be contiguous, a loop in nspredef.c
+ * depends on this.
+ */
+#define ACPI_RTYPE_ANY                  0x00
+#define ACPI_RTYPE_NONE                 0x01
+#define ACPI_RTYPE_INTEGER              0x02
+#define ACPI_RTYPE_STRING               0x04
+#define ACPI_RTYPE_BUFFER               0x08
+#define ACPI_RTYPE_PACKAGE              0x10
+#define ACPI_RTYPE_REFERENCE            0x20
+#define ACPI_RTYPE_ALL                  0x3F
+
+#define ACPI_NUM_RTYPES                 5	/* Number of actual object types */
+
 /*****************************************************************************
  *
  * Event typedefs and structs

include/acpi/acnamesp.h

@@ -177,6 +177,22 @@ acpi_ns_dump_objects(acpi_object_type type,
  */
 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info *info);
 
+/*
+ * nspredef - Support for predefined/reserved names
+ */
+acpi_status
+acpi_ns_check_predefined_names(struct acpi_namespace_node *node,
+			       union acpi_operand_object *return_object);
+
+const union acpi_predefined_info *acpi_ns_check_for_predefined_name(struct
+								    acpi_namespace_node
+								    *node);
+
+void
+acpi_ns_check_parameter_count(char *pathname,
+			      struct acpi_namespace_node *node,
+			      const union acpi_predefined_info *info);
+
 /*
  * nsnames - Name and Scope manipulation
  */