ACPICA: acpidump: Fix truncated RSDP signature validation.

This patch enforces a rule to always use ACPI_VALIDATE_RSDP_SIG for RSDP
signatures passed from table header or ACPI_SIG_RSDP so that truncated
string comparison can be avoided.  This could help to fix the issue that
"RSD " matches but "RSD PTR " doesn't match.  Lv Zheng.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 31 insertions, 10 deletions

diff --git a/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c b/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
index dc6509884c25..a8cd344d621b 100644
--- a/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
+++ b/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
@@ -996,10 +996,21 @@ osl_map_table(acpi_size address,
 
         /* If specified, signature must match */
 
-        if (signature && !ACPI_COMPARE_NAME(signature, mapped_table->signature)) {
-                acpi_os_unmap_memory(mapped_table,
-                                     sizeof(struct acpi_table_header));
-                return (AE_BAD_SIGNATURE);
+        if (signature) {
+                if (ACPI_VALIDATE_RSDP_SIG(signature)) {
+                        if (!ACPI_VALIDATE_RSDP_SIG(mapped_table->signature)) {
+                                acpi_os_unmap_memory(mapped_table,
+                                                     sizeof(struct
+                                                            acpi_table_header));
+                                return (AE_BAD_SIGNATURE);
+                        }
+                } else
+                    if (!ACPI_COMPARE_NAME(signature, mapped_table->signature))
+                {
+                        acpi_os_unmap_memory(mapped_table,
+                                             sizeof(struct acpi_table_header));
+                        return (AE_BAD_SIGNATURE);
+                }
         }
 
         /* Map the entire table */
@@ -1135,12 +1146,22 @@ osl_read_table_from_file(char *filename,
 
         /* If signature is specified, it must match the table */
 
-        if (signature && !ACPI_COMPARE_NAME(signature, header.signature)) {
-                fprintf(stderr,
-                        "Incorrect signature: Expecting %4.4s, found %4.4s\n",
-                        signature, header.signature);
-                status = AE_BAD_SIGNATURE;
-                goto exit;
+        if (signature) {
+                if (ACPI_VALIDATE_RSDP_SIG(signature)) {
+                        if (!ACPI_VALIDATE_RSDP_SIG(header.signature)) {
+                                fprintf(stderr,
+                                        "Incorrect RSDP signature: found %8.8s\n",
+                                        header.signature);
+                                status = AE_BAD_SIGNATURE;
+                                goto exit;
+                        }
+                } else if (!ACPI_COMPARE_NAME(signature, header.signature)) {
+                        fprintf(stderr,
+                                "Incorrect signature: Expecting %4.4s, found %4.4s\n",
+                                signature, header.signature);
+                        status = AE_BAD_SIGNATURE;
+                        goto exit;
+                }
         }
 
         table_length = ap_get_table_length(&header);