--- a/mt7603_mac.c
+++ b/mt7603_mac.c
@@ -474,7 +474,7 @@
 	bool stbc = false;
 	int n_rates = sta->n_rates;
 	u8 bw, bw_prev, bw_idx = 0;
-	u16 val[8];
+	u16 val[8] = { 0 };
 	u32 w9 = mt76_rr(dev, addr + 9 * 4);
 	int count;
 	int i;
