net: ethernet: renesas: ravb_main: test clock rate to avoid division by 0

Wolfram Sang · davem330 · commit a6d37131c02f · 2016-04-13T22:36:28.000-04:00
The clk API may return 0 on clk_get_rate, so we should check the result before
using it as a divisor.

Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Acked-by: Sergei Shtylyov &lt;sergei.shtylyov@cogentembedded.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
@@ -1691,6 +1691,9 @@ static int ravb_set_gti(struct net_device *ndev)
 	rate = clk_get_rate(clk);
 	clk_put(clk);
 
+	if (!rate)
+		return -EINVAL;
+
 	inc = 1000000000ULL << 20;
 	do_div(inc, rate);
 
