ACPICA: Fix memory leak caused by _CID repair function

ACPICA commit 180cb53963aa876c782a6f52cc155d951b26051a

According to the ACPI spec, _CID returns a package containing
hardware ID's. Each element of an ASL package contains a reference
count from the parent package as well as the element itself.

Name (TEST, Package() {
    "String object" // this package element has a reference count of 2
})

A memory leak was caused in the _CID repair function because it did
not decrement the reference count created by the package. Fix the
memory leak by calling acpi_ut_remove_reference on _CID package elements
that represent a hardware ID (_HID).

Link: https://github.com/acpica/acpica/commit/180cb539
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Erik Kaneda <erik.kaneda@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/acpica/nsrepair2.c b/drivers/acpi/acpica/nsrepair2.c
index 14b71b4..38e10ab 100644 (file)
--- a/drivers/acpi/acpica/nsrepair2.c
+++ b/drivers/acpi/acpica/nsrepair2.c
@@ -379,6 +379,13 @@ acpi_ns_repair_CID(struct acpi_evaluate_info *info,
 
                        (*element_ptr)->common.reference_count =
                            original_ref_count;
+
+                       /*
+                        * The original_element holds a reference from the package object
+                        * that represents _HID. Since a new element was created by _HID,
+                        * remove the reference from the _CID package.
+                        */
+                       acpi_ut_remove_reference(original_element);
                }
 
                element_ptr++;