fx2lafw: Safer use of libusb_get_device_list

diff --git a/hardware/fx2lafw/fx2lafw.c b/hardware/fx2lafw/fx2lafw.c
index bce5cd08c6632559e2130c3fd9491649d9c513ea..42d994d953ac55764e3782996797edee932a5201 100644 (file)
--- a/hardware/fx2lafw/fx2lafw.c
+++ b/hardware/fx2lafw/fx2lafw.c
@@ -175,8 +175,14 @@ static int fx2lafw_dev_open(int dev_index)
                return SR_ERR;
 
        skip = 0;
-       libusb_get_device_list(usb_context, &devlist);
-       for (i = 0; devlist[i]; i++) {
+       const int device_count = libusb_get_device_list(usb_context, &devlist);
+       if (device_count < 0) {
+               sr_err("fx2lafw: Failed to retrieve device list (%d)",
+                       device_count);
+               return SR_ERR;
+       }
+
+       for (i = 0; i < device_count; i++) {
                if ((ret = libusb_get_device_descriptor(devlist[i], &des))) {
                        sr_err("fx2lafw: Failed to get device descriptor: %d.",
                               ret);