net: stmmac: Fixed mtu channged by cache aligned

[ Upstream commit 5b55299eed78538cc4746e50ee97103a1643249c ]

Since the original mtu is not used when the mtu is updated,
the mtu is aligned with cache, this will get an incorrect.
For example, if you want to configure the mtu to be 1500,
but mtu 1536 is configured in fact.

Fixed: eaf4fac478 ("net: stmmac: Do not accept invalid MTU values")
Signed-off-by: David Wu <david.wu@rock-chips.com>
Link: https://lore.kernel.org/r/20210113034109.27865-1-david.wu@rock-chips.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
David Wu 2021-01-13 11:41:09 +08:00 committed by Greg Kroah-Hartman
parent 741690db7a
commit 5ae7725043

View File

@ -3996,6 +3996,7 @@ 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;
const int mtu = new_mtu;
if (txfifosz == 0)
txfifosz = priv->dma_cap.tx_fifo_size;
@ -4013,7 +4014,7 @@ static int stmmac_change_mtu(struct net_device *dev, int new_mtu)
if ((txfifosz < new_mtu) || (new_mtu > BUF_SIZE_16KiB))
return -EINVAL;
dev->mtu = new_mtu;
dev->mtu = mtu;
netdev_update_features(dev);