diff --git a/sys/bus/u4b/wlan/if_rum.c b/sys/bus/u4b/wlan/if_rum.c
--- a/sys/bus/u4b/wlan/if_rum.c
+++ b/sys/bus/u4b/wlan/if_rum.c
@@ -2088,7 +2088,11 @@
 		  sc->rf_rev == RT2573_RF_2527) ? rum_rf5225 : rum_rf5226;
 
 	/* find the settings for this channel (we know it exists) */
-	for (i = 0; rfprog[i].chan != chan; i++);
+	for (i = 0; i < nitems(rum_rf5226); i++)
+		if (rfprog[i].chan == chan)
+			break;
+	if (i == nitems(rum_rf5226))
+		return;
 
 	power = sc->txpow[i];
 	if (power < 0) {