[PATCH 1/2] net: ll_temac: fix DMA resources leak

From: Jonas Suhr Christensen
Date: Thu Jan 26 2023 - 05:17:23 EST


Add missing conversion of address when unmapping dma region causing
unmapping to silently fail. At some point resulting in buffer
overrun eg. when releasing device.

Signed-off-by: Jonas Suhr Christensen <jsc@xxxxxxxxxxxxxx>
---
drivers/net/ethernet/xilinx/ll_temac_main.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c
index 1066420d6a83..66c04027f230 100644
--- a/drivers/net/ethernet/xilinx/ll_temac_main.c
+++ b/drivers/net/ethernet/xilinx/ll_temac_main.c
@@ -300,6 +300,7 @@ static void temac_dma_bd_release(struct net_device *ndev)
{
struct temac_local *lp = netdev_priv(ndev);
int i;
+ struct cdmac_bd *bd;

/* Reset Local Link (DMA) */
lp->dma_out(lp, DMA_CONTROL_REG, DMA_CONTROL_RST);
@@ -307,9 +308,14 @@ static void temac_dma_bd_release(struct net_device *ndev)
for (i = 0; i < lp->rx_bd_num; i++) {
if (!lp->rx_skb[i])
break;
- dma_unmap_single(ndev->dev.parent, lp->rx_bd_v[i].phys,
+
+ bd = &lp->rx_bd_v[1];
+ dma_unmap_single(ndev->dev.parent, be32_to_cpu(bd->phys),
XTE_MAX_JUMBO_FRAME_SIZE, DMA_FROM_DEVICE);
+ bd->phys = 0;
+ bd->len = 0;
dev_kfree_skb(lp->rx_skb[i]);
+ lp->rx_skb[i] = NULL;
}
if (lp->rx_bd_v)
dma_free_coherent(ndev->dev.parent,
--
2.39.1