ACPICA: Fix for LoadTable operator, input strings

Fixed a problem with the LoadTable operator where the OemId
and OemTableId input strings could cause unexpected failures if
they were shorter than the maximum lengths allowed.

http://www.acpica.org/bugzilla/show_bug.cgi?id=576

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 23 insertions, 9 deletions

diff --git a/drivers/acpi/tables/tbfind.c b/drivers/acpi/tables/tbfind.c
index 058c064948e1..772ca41d840b 100644
--- a/drivers/acpi/tables/tbfind.c
+++ b/drivers/acpi/tables/tbfind.c
@@ -70,12 +70,22 @@ acpi_tb_find_table(char *signature,
 {
         acpi_native_uint i;
         acpi_status status;
+        struct acpi_table_header header;
 
         ACPI_FUNCTION_TRACE(tb_find_table);
 
+        /* Normalize the input strings */
+
+        ACPI_MEMSET(&header, 0, sizeof(struct acpi_table_header));
+        ACPI_STRNCPY(header.signature, signature, ACPI_NAME_SIZE);
+        ACPI_STRNCPY(header.oem_id, oem_id, ACPI_OEM_ID_SIZE);
+        ACPI_STRNCPY(header.oem_table_id, oem_table_id, ACPI_OEM_TABLE_ID_SIZE);
+
+        /* Search for the table */
+
         for (i = 0; i < acpi_gbl_root_table_list.count; ++i) {
                 if (ACPI_MEMCMP(&(acpi_gbl_root_table_list.tables[i].signature),
-                                signature, ACPI_NAME_SIZE)) {
+                                header.signature, ACPI_NAME_SIZE)) {
 
                         /* Not the requested table */
 
@@ -104,20 +114,24 @@ acpi_tb_find_table(char *signature,
 
                 if (!ACPI_MEMCMP
                     (acpi_gbl_root_table_list.tables[i].pointer->signature,
-                     signature, ACPI_NAME_SIZE) && (!oem_id[0]
-                                                    ||
-                                                    !ACPI_MEMCMP
-                                                    (acpi_gbl_root_table_list.
-                                                     tables[i].pointer->oem_id,
-                                                     oem_id, ACPI_OEM_ID_SIZE))
+                     header.signature, ACPI_NAME_SIZE) && (!oem_id[0]
+                                                           ||
+                                                           !ACPI_MEMCMP
+                                                           (acpi_gbl_root_table_list.
+                                                            tables[i].pointer->
+                                                            oem_id,
+                                                            header.oem_id,
+                                                            ACPI_OEM_ID_SIZE))
                     && (!oem_table_id[0]
                         || !ACPI_MEMCMP(acpi_gbl_root_table_list.tables[i].
-                                        pointer->oem_table_id, oem_table_id,
+                                        pointer->oem_table_id,
+                                        header.oem_table_id,
                                         ACPI_OEM_TABLE_ID_SIZE))) {
                         *table_index = i;
 
                         ACPI_DEBUG_PRINT((ACPI_DB_TABLES,
-                                          "Found table [%4.4s]\n", signature));
+                                          "Found table [%4.4s]\n",
+                                          header.signature));
                         return_ACPI_STATUS(AE_OK);
                 }
         }