diff --git a/hw/usb/bus.c b/hw/usb/bus.c
index fe70429304..e48b19fc29 100644
--- a/hw/usb/bus.c
+++ b/hw/usb/bus.c
@@ -49,7 +49,9 @@ static int usb_device_post_load(void *opaque, int version_id)
     } else {
         dev->attached = 1;
     }
-    if (dev->setup_index >= sizeof(dev->data_buf) ||
+    if (dev->setup_index < 0 ||
+        dev->setup_len < 0 ||
+        dev->setup_index >= sizeof(dev->data_buf) ||
         dev->setup_len >= sizeof(dev->data_buf)) {
         return -EINVAL;
     }