net: lantiq_etop: don't free skb when returning NETDEV_TX_BUSY

stable inclusion
from stable-v5.10.153
commit aab883bd60bcd682b1ccd0bf94989fbabf2f9ad5
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I64YCA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=aab883bd60bcd682b1ccd0bf94989fbabf2f9ad5

--------------------------------

[ Upstream commit 9c1eaa27 ]

The ndo_start_xmit() method must not free skb when returning
NETDEV_TX_BUSY, since caller is going to requeue freed skb.

Fixes: 504d4721 ("MIPS: Lantiq: Add ethernet driver")
Signed-off-by: NZhang Changzhong <zhangchangzhong@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NLipeng Sang <sanglipeng1@jd.com>

drivers/net/ethernet/lantiq_etop.c

@@ -466,7 +466,6 @@ ltq_etop_tx(struct sk_buff *skb, struct net_device *dev)
 	len = skb->len < ETH_ZLEN ? ETH_ZLEN : skb->len;
 
 	if ((desc->ctl & (LTQ_DMA_OWN | LTQ_DMA_C)) || ch->skb[ch->dma.desc]) {
-		dev_kfree_skb_any(skb);
 		netdev_err(dev, "tx ring full\n");
 		netif_tx_stop_queue(txq);
 		return NETDEV_TX_BUSY;