ACPICA: Region deletion: Ensure region object is removed from handler list

Prevents a possible fault when a dynamic operation region is
deleted. ACPICA BZ 507.

http://acpica.org/bugzilla/show_bug.cgi?id=507

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/acpica/utdelete.c b/drivers/acpi/acpica/utdelete.c
index a5ee23b..bc17103 100644 (file)
--- a/drivers/acpi/acpica/utdelete.c
+++ b/drivers/acpi/acpica/utdelete.c
@@ -75,6 +75,7 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
        union acpi_operand_object *handler_desc;
        union acpi_operand_object *second_desc;
        union acpi_operand_object *next_desc;
+       union acpi_operand_object **last_obj_ptr;
 
        ACPI_FUNCTION_TRACE_PTR(ut_delete_internal_obj, object);
 
@@ -223,6 +224,26 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object)
                         */
                        handler_desc = object->region.handler;
                        if (handler_desc) {
+                               next_desc =
+                                   handler_desc->address_space.region_list;
+                               last_obj_ptr =
+                                   &handler_desc->address_space.region_list;
+
+                               /* Remove the region object from the handler's list */
+
+                               while (next_desc) {
+                                       if (next_desc == object) {
+                                               *last_obj_ptr =
+                                                   next_desc->region.next;
+                                               break;
+                                       }
+
+                                       /* Walk the linked list of handler */
+
+                                       last_obj_ptr = &next_desc->region.next;
+                                       next_desc = next_desc->region.next;
+                               }
+
                                if (handler_desc->address_space.handler_flags &
                                    ACPI_ADDR_HANDLER_DEFAULT_INSTALLED) {