diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index eccbf5daf9ed1161f7b09492001f6f5663eeaf47..8b7861909ef9c6c8a0f13bf8c05467602cfca0b7 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3827,12 +3827,24 @@ static void stmmac_set_rx_mode(struct net_device *dev) static int stmmac_change_mtu(struct net_device *dev, int new_mtu) { struct stmmac_priv *priv = netdev_priv(dev); + int txfifosz = priv->plat->tx_fifo_size; + + if (txfifosz == 0) + txfifosz = priv->dma_cap.tx_fifo_size; + + txfifosz /= priv->plat->tx_queues_to_use; if (netif_running(dev)) { netdev_err(priv->dev, "must be stopped to change its MTU\n"); return -EBUSY; } + new_mtu = STMMAC_ALIGN(new_mtu); + + /* If condition true, FIFO is too small or MTU too large */ + if ((txfifosz < new_mtu) || (new_mtu > BUF_SIZE_16KiB)) + return -EINVAL; + dev->mtu = new_mtu; netdev_update_features(dev);