USB: serial: replace runtime overflow check
authorJohan Hovold <johan@kernel.org>
Thu, 2 Mar 2017 11:51:18 +0000 (12:51 +0100)
committerJohan Hovold <johan@kernel.org>
Thu, 16 Mar 2017 09:33:41 +0000 (10:33 +0100)
Since commit 0a8fd1346254 ("USB: fix problems with duplicate endpoint
addresses") USB core guarantees that there are no more than 15 endpoint
descriptors per type (and altsetting) so the corresponding overflow
checks can now be replaced with a compile-time check on the array sizes
(and indirectly the maximum number of ports).

Signed-off-by: Johan Hovold <johan@kernel.org>
drivers/usb/serial/usb-serial.c

index 09eb639298c8b798ebaed5b5cc624c2e004c851f..ccc729d17a896b02a5208c10ab13ff3c923502ed 100644 (file)
@@ -729,29 +729,26 @@ static void find_endpoints(struct usb_serial *serial,
        struct usb_endpoint_descriptor *epd;
        unsigned int i;
 
+       BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_in) < USB_MAXENDPOINTS / 2);
+       BUILD_BUG_ON(ARRAY_SIZE(epds->bulk_out) < USB_MAXENDPOINTS / 2);
+       BUILD_BUG_ON(ARRAY_SIZE(epds->interrupt_in) < USB_MAXENDPOINTS / 2);
+       BUILD_BUG_ON(ARRAY_SIZE(epds->interrupt_out) < USB_MAXENDPOINTS / 2);
+
        iface_desc = serial->interface->cur_altsetting;
        for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
                epd = &iface_desc->endpoint[i].desc;
 
                if (usb_endpoint_is_bulk_in(epd)) {
                        dev_dbg(dev, "found bulk in on endpoint %u\n", i);
-                       if (epds->num_bulk_in == MAX_NUM_PORTS)
-                               continue;
                        epds->bulk_in[epds->num_bulk_in++] = epd;
                } else if (usb_endpoint_is_bulk_out(epd)) {
                        dev_dbg(dev, "found bulk out on endpoint %u\n", i);
-                       if (epds->num_bulk_out == MAX_NUM_PORTS)
-                               continue;
                        epds->bulk_out[epds->num_bulk_out++] = epd;
                } else if (usb_endpoint_is_int_in(epd)) {
                        dev_dbg(dev, "found interrupt in on endpoint %u\n", i);
-                       if (epds->num_interrupt_in == MAX_NUM_PORTS)
-                               continue;
                        epds->interrupt_in[epds->num_interrupt_in++] = epd;
                } else if (usb_endpoint_is_int_out(epd)) {
                        dev_dbg(dev, "found interrupt out on endpoint %u\n", i);
-                       if (epds->num_interrupt_out == MAX_NUM_PORTS)
-                               continue;
                        epds->interrupt_out[epds->num_interrupt_out++] = epd;
                }
        }