ACPICA: Additional error checking for pathname utilities

Add error check after all calls to acpi_ns_get_pathname_length.
Add status return from acpi_ns_build_external_path and check after
all calls.  Add parameter validation to acpi_ut_initialize_buffer.

Reported by and initial patch by Ingo Molnar.
http://lkml.org/lkml/2008/7/21/176

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>

2 files changed, 14 insertions, 7 deletions

diff --git a/drivers/acpi/utilities/utalloc.c b/drivers/acpi/utilities/utalloc.c
index e7bf34a7b1d2..7dcb67e0b215 100644
--- a/drivers/acpi/utilities/utalloc.c
+++ b/drivers/acpi/utilities/utalloc.c
@@ -242,10 +242,12 @@ acpi_ut_initialize_buffer(struct acpi_buffer * buffer,
 {
         acpi_status status = AE_OK;
 
-        if (!required_length) {
-                WARN_ON(1);
-                return AE_ERROR;
+        /* Parameter validation */
+
+        if (!buffer || !required_length) {
+                return (AE_BAD_PARAMETER);
         }
+
         switch (buffer->length) {
         case ACPI_NO_BUFFER:
 
diff --git a/drivers/acpi/utilities/utobject.c b/drivers/acpi/utilities/utobject.c
index e25484495e65..916eff399eb3 100644
--- a/drivers/acpi/utilities/utobject.c
+++ b/drivers/acpi/utilities/utobject.c
@@ -425,6 +425,7 @@ acpi_ut_get_simple_object_size(union acpi_operand_object *internal_object,
                                acpi_size * obj_length)
 {
         acpi_size length;
+        acpi_size size;
         acpi_status status = AE_OK;
 
         ACPI_FUNCTION_TRACE_PTR(ut_get_simple_object_size, internal_object);
@@ -484,10 +485,14 @@ acpi_ut_get_simple_object_size(union acpi_operand_object *internal_object,
                          * Get the actual length of the full pathname to this object.
                          * The reference will be converted to the pathname to the object
                          */
-                        length +=
-                            ACPI_ROUND_UP_TO_NATIVE_WORD
-                            (acpi_ns_get_pathname_length
-                             (internal_object->reference.node));
+                        size =
+                            acpi_ns_get_pathname_length(internal_object->
+                                                        reference.node);
+                        if (!size) {
+                                return_ACPI_STATUS(AE_BAD_PARAMETER);
+                        }
+
+                        length += ACPI_ROUND_UP_TO_NATIVE_WORD(size);
                         break;
 
                 default: