--- sys/bus/u4b/misc/ufm.c.orig	2026-10-07
+++ sys/bus/u4b/misc/ufm.c	2026-10-07
@@ -180,7 +180,7 @@
 	int error;
 
 	struct usb_device_request req;
-	uint8_t buf[1];
+	uint8_t buf[1] = {0};
 
 	req.bmRequestType = UT_READ_VENDOR_DEVICE;
 	req.bRequest = request;