diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 99272a67525c..c2f1a542e6fa 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -2013,7 +2013,8 @@ static int ethtool_phys_id(struct net_device *dev, void __user *useraddr)
 	} else {
 		/* Driver expects to be called at twice the frequency in rc */
 		int n = rc * 2, interval = HZ / n;
-		u64 count = n * id.data, i = 0;
+		u64 count = mul_u32_u32(n, id.data);
+		u64 i = 0;
 
 		do {
 			rtnl_lock();