ACPICA: Fix possible negative array index in acpi_ut_validate_exception

Added NULL fields to the exception string arrays to eliminate
the -1 subtraction on the SubStatus field.
Signed-off-by: NBob Moore <robert.moore@intel.com>
Signed-off-by: NLin Ming <ming.m.lin@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>
Signed-off-by: NAndi Kleen <ak@linux.intel.com>

drivers/acpi/utilities/utmisc.c

@@ -64,7 +64,7 @@ ACPI_MODULE_NAME("utmisc")
  ******************************************************************************/
 const char *acpi_ut_validate_exception(acpi_status status)
 {
-	acpi_status sub_status;
+	u32 sub_status;
 	const char *exception = NULL;
 
 	ACPI_FUNCTION_ENTRY();
@@ -85,32 +85,28 @@ const char *acpi_ut_validate_exception(acpi_status status)
 	case AE_CODE_PROGRAMMER:
 
 		if (sub_status <= AE_CODE_PGM_MAX) {
-			exception =
-			    acpi_gbl_exception_names_pgm[sub_status - 1];
+			exception = acpi_gbl_exception_names_pgm[sub_status];
 		}
 		break;
 
 	case AE_CODE_ACPI_TABLES:
 
 		if (sub_status <= AE_CODE_TBL_MAX) {
-			exception =
-			    acpi_gbl_exception_names_tbl[sub_status - 1];
+			exception = acpi_gbl_exception_names_tbl[sub_status];
 		}
 		break;
 
 	case AE_CODE_AML:
 
 		if (sub_status <= AE_CODE_AML_MAX) {
-			exception =
-			    acpi_gbl_exception_names_aml[sub_status - 1];
+			exception = acpi_gbl_exception_names_aml[sub_status];
 		}
 		break;
 
 	case AE_CODE_CONTROL:
 
 		if (sub_status <= AE_CODE_CTRL_MAX) {
-			exception =
-			    acpi_gbl_exception_names_ctrl[sub_status - 1];
+			exception = acpi_gbl_exception_names_ctrl[sub_status];
 		}
 		break;
 

include/acpi/acexcep.h

@@ -226,6 +226,7 @@ char const *acpi_gbl_exception_names_env[] = {
 };
 
 char const *acpi_gbl_exception_names_pgm[] = {
+	NULL,
 	"AE_BAD_PARAMETER",
 	"AE_BAD_CHARACTER",
 	"AE_BAD_PATHNAME",
@@ -239,6 +240,7 @@ char const *acpi_gbl_exception_names_pgm[] = {
 };
 
 char const *acpi_gbl_exception_names_tbl[] = {
+	NULL,
 	"AE_BAD_SIGNATURE",
 	"AE_BAD_HEADER",
 	"AE_BAD_CHECKSUM",
@@ -248,6 +250,7 @@ char const *acpi_gbl_exception_names_tbl[] = {
 };
 
 char const *acpi_gbl_exception_names_aml[] = {
+	NULL,
 	"AE_AML_ERROR",
 	"AE_AML_PARSE",
 	"AE_AML_BAD_OPCODE",
@@ -285,6 +288,7 @@ char const *acpi_gbl_exception_names_aml[] = {
 };
 
 char const *acpi_gbl_exception_names_ctrl[] = {
+	NULL,
 	"AE_CTRL_RETURN_VALUE",
 	"AE_CTRL_PENDING",
 	"AE_CTRL_TERMINATE",