diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 4482cf28f56a..d573f201295a 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -927,6 +927,13 @@ static int acpi_processor_evaluate_lpi(acpi_handle handle, if (obj->type == ACPI_TYPE_BUFFER) { struct acpi_power_register *reg; + if (obj->buffer.length < sizeof(*reg)) { + acpi_handle_debug(handle, + "Invalid register data for _LPI state %d\n", + state_idx); + continue; + } + reg = (struct acpi_power_register *)obj->buffer.pointer; if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) @@ -945,13 +952,6 @@ static int acpi_processor_evaluate_lpi(acpi_handle handle, continue; } - /* elements[7,8] skipped for now i.e. Residency/Usage counter*/ - - obj = pkg_elem + 9; - if (obj->type == ACPI_TYPE_STRING) - strscpy(lpi_state->desc, obj->string.pointer, - ACPI_CX_DESC_LEN); - lpi_state->index = state_idx; if (obj_get_integer(pkg_elem + 0, &lpi_state->min_residency)) { pr_debug("No min. residency found, assuming 10 us\n"); @@ -974,6 +974,20 @@ static int acpi_processor_evaluate_lpi(acpi_handle handle, if (obj_get_integer(pkg_elem + 5, &lpi_state->enable_parent_state)) lpi_state->enable_parent_state = 0; + + /* Skip elements [7-8] i.e. Residency/Usage counters. */ + + /* + * Avoid out-of-bounds access if the size of the package is less + * than expected. + */ + if (element->package.count < 10) + continue; + + obj = pkg_elem + 9; + if (obj->type == ACPI_TYPE_STRING) + strscpy(lpi_state->desc, obj->string.pointer, + ACPI_CX_DESC_LEN); } acpi_handle_debug(handle, "Found %d power states\n", state_idx);