IB/mlx4: Fix memory leak in __mlx4_ib_modify_qp

commit bede98e7 upstream.

In case handle_eth_ud_smac_index fails, we need to free the allocated resources.

Fixes: 2f5bb473 ("mlx4: Add ref counting to port MAC table for RoCE")
Signed-off-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/infiniband/hw/mlx4/qp.c

@@ -1674,8 +1674,10 @@ static int __mlx4_ib_modify_qp(struct ib_qp *ibqp,
 			    qp->mlx4_ib_qp_type == MLX4_IB_QPT_PROXY_GSI ||
 			    qp->mlx4_ib_qp_type == MLX4_IB_QPT_TUN_GSI) {
 				err = handle_eth_ud_smac_index(dev, qp, (u8 *)attr->smac, context);
-				if (err)
-					return -EINVAL;
+				if (err) {
+					err = -EINVAL;
+					goto out;
+				}
 				if (qp->mlx4_ib_qp_type == MLX4_IB_QPT_PROXY_GSI)
 					dev->qp1_proxy[qp->port - 1] = qp;
 			}