1 files changed, 19 insertions, 2 deletions

diff --git a/drivers/acpi/acpica/exconfig.c b/drivers/acpi/acpica/exconfig.c
index c0348ff9a602..0731fd6bad63 100644
--- a/drivers/acpi/acpica/exconfig.c
+++ b/drivers/acpi/acpica/exconfig.c
@@ -91,6 +91,7 @@ acpi_ex_add_table(u32 table_index,
 
         /* Init the table handle */
 
+        obj_desc->common.flags |= AOPOBJ_DATA_VALID;
         obj_desc->reference.class = ACPI_REFCLASS_TABLE;
         *ddb_handle = obj_desc;
 
@@ -501,13 +502,18 @@ acpi_status acpi_ex_unload_table(union acpi_operand_object *ddb_handle)
 
         /*
          * Validate the handle
-         * Although the handle is partially validated in acpi_ex_reconfiguration(),
+         * Although the handle is partially validated in acpi_ex_reconfiguration()
          * when it calls acpi_ex_resolve_operands(), the handle is more completely
          * validated here.
+         *
+         * Handle must be a valid operand object of type reference. Also, the
+         * ddb_handle must still be marked valid (table has not been previously
+         * unloaded)
          */
         if ((!ddb_handle) ||
             (ACPI_GET_DESCRIPTOR_TYPE(ddb_handle) != ACPI_DESC_TYPE_OPERAND) ||
-            (ddb_handle->common.type != ACPI_TYPE_LOCAL_REFERENCE)) {
+            (ddb_handle->common.type != ACPI_TYPE_LOCAL_REFERENCE) ||
+            (!(ddb_handle->common.flags & AOPOBJ_DATA_VALID))) {
                 return_ACPI_STATUS(AE_BAD_PARAMETER);
         }
 
@@ -515,6 +521,12 @@ acpi_status acpi_ex_unload_table(union acpi_operand_object *ddb_handle)
 
         table_index = table_desc->reference.value;
 
+        /* Ensure the table is still loaded */
+
+        if (!acpi_tb_is_table_loaded(table_index)) {
+                return_ACPI_STATUS(AE_NOT_EXIST);
+        }
+
         /* Invoke table handler if present */
 
         if (acpi_gbl_table_handler) {
@@ -536,5 +548,10 @@ acpi_status acpi_ex_unload_table(union acpi_operand_object *ddb_handle)
         (void)acpi_tb_release_owner_id(table_index);
         acpi_tb_set_table_loaded_flag(table_index, FALSE);
 
+        /*
+         * Invalidate the handle. We do this because the handle may be stored
+         * in a named object and may not be actually deleted until much later.
+         */
+        ddb_handle->common.flags &= ~AOPOBJ_DATA_VALID;
         return_ACPI_STATUS(AE_OK);
 }