From b530b16413b7f99977ded50a3c4bebd2ea79c41b Mon Sep 17 00:00:00 2001 From: Alexander Kochetkov Date: Tue, 9 Feb 2016 18:20:40 +0300 Subject: [PATCH] net: arc_emac: fix sk_buff leak EMAC could be disabled, while there is some sb_buff in use. That buffers got lost for linux. In order to reproduce run on device during active ethernet work: ifconfig eth0 down Signed-off-by: Alexander Kochetkov Signed-off-by: David S. Miller --- drivers/net/ethernet/arc/emac_main.c | 62 ++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) diff --git a/drivers/net/ethernet/arc/emac_main.c b/drivers/net/ethernet/arc/emac_main.c index 4f6e5be184df..6446af1403f7 100644 --- a/drivers/net/ethernet/arc/emac_main.c +++ b/drivers/net/ethernet/arc/emac_main.c @@ -517,6 +517,64 @@ static void arc_emac_set_rx_mode(struct net_device *ndev) } } +/** + * arc_free_tx_queue - free skb from tx queue + * @ndev: Pointer to the network device. + * + * This function must be called while EMAC disable + */ +static void arc_free_tx_queue(struct net_device *ndev) +{ + struct arc_emac_priv *priv = netdev_priv(ndev); + unsigned int i; + + for (i = 0; i < TX_BD_NUM; i++) { + struct arc_emac_bd *txbd = &priv->txbd[i]; + struct buffer_state *tx_buff = &priv->tx_buff[i]; + + if (tx_buff->skb) { + dma_unmap_single(&ndev->dev, dma_unmap_addr(tx_buff, addr), + dma_unmap_len(tx_buff, len), DMA_TO_DEVICE); + + /* return the sk_buff to system */ + dev_kfree_skb_irq(tx_buff->skb); + } + + txbd->info = 0; + txbd->data = 0; + tx_buff->skb = NULL; + } +} + +/** + * arc_free_rx_queue - free skb from rx queue + * @ndev: Pointer to the network device. + * + * This function must be called while EMAC disable + */ +static void arc_free_rx_queue(struct net_device *ndev) +{ + struct arc_emac_priv *priv = netdev_priv(ndev); + unsigned int i; + + for (i = 0; i < RX_BD_NUM; i++) { + struct arc_emac_bd *rxbd = &priv->rxbd[i]; + struct buffer_state *rx_buff = &priv->rx_buff[i]; + + if (rx_buff->skb) { + dma_unmap_single(&ndev->dev, dma_unmap_addr(rx_buff, addr), + dma_unmap_len(rx_buff, len), DMA_FROM_DEVICE); + + /* return the sk_buff to system */ + dev_kfree_skb_irq(rx_buff->skb); + } + + rxbd->info = 0; + rxbd->data = 0; + rx_buff->skb = NULL; + } +} + /** * arc_emac_stop - Close the network device. * @ndev: Pointer to the network device. @@ -538,6 +596,10 @@ static int arc_emac_stop(struct net_device *ndev) /* Disable EMAC */ arc_reg_clr(priv, R_CTRL, EN_MASK); + /* Return the sk_buff to system */ + arc_free_tx_queue(ndev); + arc_free_rx_queue(ndev); + return 0; } -- 2.20.1