1 files changed, 31 insertions, 4 deletions

diff --git a/drivers/acpi/dispatcher/dsobject.c b/drivers/acpi/dispatcher/dsobject.c
index 58d4d91c8e97..7562823b3b76 100644
--- a/drivers/acpi/dispatcher/dsobject.c
+++ b/drivers/acpi/dispatcher/dsobject.c
@@ -373,7 +373,7 @@ acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
         union acpi_parse_object *parent;
         union acpi_operand_object *obj_desc = NULL;
         acpi_status status = AE_OK;
-        acpi_native_uint i;
+        unsigned i;
         u16 index;
         u16 reference_count;
 
@@ -476,10 +476,37 @@ acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
                 arg = arg->common.next;
         }
 
-        if (!arg) {
+        /* Check for match between num_elements and actual length of package_list */
+
+        if (arg) {
+                /*
+                 * num_elements was exhausted, but there are remaining elements in the
+                 * package_list.
+                 *
+                 * Note: technically, this is an error, from ACPI spec: "It is an error
+                 * for NumElements to be less than the number of elements in the
+                 * PackageList". However, for now, we just print an error message and
+                 * no exception is returned.
+                 */
+                while (arg) {
+
+                        /* Find out how many elements there really are */
+
+                        i++;
+                        arg = arg->common.next;
+                }
+
+                ACPI_ERROR((AE_INFO,
+                            "Package List length (%X) larger than NumElements count (%X), truncated\n",
+                            i, element_count));
+        } else if (i < element_count) {
+                /*
+                 * Arg list (elements) was exhausted, but we did not reach num_elements count.
+                 * Note: this is not an error, the package is padded out with NULLs.
+                 */
                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                  "Package List length larger than NumElements count (%X), truncated\n",
-                                  element_count));
+                                  "Package List length (%X) smaller than NumElements count (%X), padded with null elements\n",
+                                  i, element_count));
         }
 
         obj_desc->package.flags |= AOPOBJ_DATA_VALID;