net/temac: FIX segfault when process old irqs

Do not enable the irq until the scatter gather registers are ready to
handle the data. Otherwise an irq from a packet send/received before
last close can lead to an access to an invalid memory region on the irq
handler.

Also, stop the dma engine on close.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c
index caf3659e173c..05a1ffad20d2 100644
--- a/drivers/net/ethernet/xilinx/ll_temac_main.c
+++ b/drivers/net/ethernet/xilinx/ll_temac_main.c
@@ -203,6 +203,9 @@ static void temac_dma_bd_release(struct net_device *ndev)
         struct temac_local *lp = netdev_priv(ndev);
         int i;
 
+        /* Reset Local Link (DMA) */
+        lp->dma_out(lp, DMA_CONTROL_REG, DMA_CONTROL_RST);
+
         for (i = 0; i < RX_BD_NUM; i++) {
                 if (!lp->rx_skb[i])
                         break;
@@ -860,6 +863,8 @@ static int temac_open(struct net_device *ndev)
                 phy_start(lp->phy_dev);
         }
 
+        temac_device_reset(ndev);
+
         rc = request_irq(lp->tx_irq, ll_temac_tx_irq, 0, ndev->name, ndev);
         if (rc)
                 goto err_tx_irq;
@@ -867,7 +872,6 @@ static int temac_open(struct net_device *ndev)
         if (rc)
                 goto err_rx_irq;
 
-        temac_device_reset(ndev);
         return 0;
 
  err_rx_irq: