From 7ea6cd16f1599c1eac6018751eadbc5fc736b99a Mon Sep 17 00:00:00 2001 From: Aleksander Jan Bajkowski Date: Tue, 15 Jun 2021 22:42:57 +0200 Subject: lantiq: net: fix duplicated skb in rx descriptor ring The previous commit didn't fix the bug properly. By mistake, it replaces the pointer of the next skb in the descriptor ring instead of the current one. As a result, the two descriptors are assigned the same SKB. The error is seen during the iperf test when skb_put tries to insert a second packet and exceeds the available buffer. Fixes: c7718ee96dbc ("net: lantiq: fix memory corruption in RX ring ") Signed-off-by: Aleksander Jan Bajkowski Signed-off-by: David S. Miller --- drivers/net/ethernet/lantiq_xrx200.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/net/ethernet/lantiq_xrx200.c') diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index 0e10d8aeffe1..21ef2f128070 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -154,6 +154,7 @@ static int xrx200_close(struct net_device *net_dev) static int xrx200_alloc_skb(struct xrx200_chan *ch) { + struct sk_buff *skb = ch->skb[ch->dma.desc]; dma_addr_t mapping; int ret = 0; @@ -168,6 +169,7 @@ static int xrx200_alloc_skb(struct xrx200_chan *ch) XRX200_DMA_DATA_LEN, DMA_FROM_DEVICE); if (unlikely(dma_mapping_error(ch->priv->dev, mapping))) { dev_kfree_skb_any(ch->skb[ch->dma.desc]); + ch->skb[ch->dma.desc] = skb; ret = -ENOMEM; goto skip; } @@ -198,7 +200,6 @@ static int xrx200_hw_receive(struct xrx200_chan *ch) ch->dma.desc %= LTQ_DESC_NUM; if (ret) { - ch->skb[ch->dma.desc] = skb; net_dev->stats.rx_dropped++; netdev_err(net_dev, "failed to allocate new rx buffer\n"); return ret; -- cgit v1.2.3-59-g8ed1b