diff --git a/drivers/acpi/acpica/exoparg3.c b/drivers/acpi/acpica/exoparg3.c
index 2fc8070814e3..2790bf1a12e7 100644
--- a/drivers/acpi/acpica/exoparg3.c
+++ b/drivers/acpi/acpica/exoparg3.c
@@ -159,7 +159,7 @@ acpi_status acpi_ex_opcode_3A_1T_1R(struct acpi_walk_state *walk_state)
 
 		/* Truncate request if larger than the actual String/Buffer */
 
-		else if ((index + length) > operand[0]->string.length) {
+		else if ((index + length) > operand[0]->string.length || (index + length) < index) {	/* Check for overflow */
 			length =
 			    (acpi_size)operand[0]->string.length -
 			    (acpi_size)index;