diff options
| author | Bob Moore <robert.moore@intel.com> | 2014-02-26 03:33:47 +0100 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2014-03-18 01:52:18 +0100 |
| commit | f953529f3b659a72c0982c2cf195158db96361f1 (patch) | |
| tree | 48eeb4fe487c2c0c82add70e8b71edea9a14f37d /drivers/acpi/acpica/utdelete.c | |
| parent | ACPICA: Debugger: Add missing objects; Traverse linked lists (diff) | |
| download | linux-f953529f3b659a72c0982c2cf195158db96361f1.tar.xz linux-f953529f3b659a72c0982c2cf195158db96361f1.zip | |
ACPICA: Prevent infinite loops when traversing corrupted lists.
This change hardens the ACPICA code to detect circular linked object
lists and prevent an infinite loop if such corruption exists.
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/acpica/utdelete.c')
| -rw-r--r-- | drivers/acpi/acpica/utdelete.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/drivers/acpi/acpica/utdelete.c b/drivers/acpi/acpica/utdelete.c index ed4cb8683310..a3516de213fa 100644 --- 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 *start_desc; union acpi_operand_object **last_obj_ptr; ACPI_FUNCTION_TRACE_PTR(ut_delete_internal_obj, object); @@ -235,10 +236,11 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object) if (handler_desc) { next_desc = handler_desc->address_space.region_list; + start_desc = next_desc; last_obj_ptr = &handler_desc->address_space.region_list; - /* Remove the region object from the handler's list */ + /* Remove the region object from the handler list */ while (next_desc) { if (next_desc == object) { @@ -247,10 +249,19 @@ static void acpi_ut_delete_internal_obj(union acpi_operand_object *object) break; } - /* Walk the linked list of handler */ + /* Walk the linked list of handlers */ last_obj_ptr = &next_desc->region.next; next_desc = next_desc->region.next; + + /* Prevent infinite loop if list is corrupted */ + + if (next_desc == start_desc) { + ACPI_ERROR((AE_INFO, + "Circular region list in address handler object %p", + handler_desc)); + return_VOID; + } } if (handler_desc->address_space.handler_flags & |