yam: fix a memory leak in yam_siocdevprivate()

ym needs to be free when ym->cmd != SIOCYAMSMCS.

Fixes: 0781168e ("yam: fix a missing-check bug")
Signed-off-by: NHangyu Hua <hbh25y@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/hamradio/yam.c

@@ -950,9 +950,7 @@ static int yam_siocdevprivate(struct net_device *dev, struct ifreq *ifr, void __
 		ym = memdup_user(data, sizeof(struct yamdrv_ioctl_mcs));
 		if (IS_ERR(ym))
 			return PTR_ERR(ym);
-		if (ym->cmd != SIOCYAMSMCS)
-			return -EINVAL;
-		if (ym->bitrate > YAM_MAXBITRATE) {
+		if (ym->cmd != SIOCYAMSMCS || ym->bitrate > YAM_MAXBITRATE) {
 			kfree(ym);
 			return -EINVAL;
 		}