[PATCH net v2 2/2] net: ll_temac: Reset buffer on dma_map_single() errors

From: Jonas Suhr Christensen
Date: Sun Feb 05 2023 - 15:12:20 EST


To avoid later calls to dma_unmap_single() on address'
that fails to be mapped, free the allocated skb and
set the pointer of the address to NULL. Eg. when a mapping
fails temac_dma_bd_release() will try to call dma_unmap_single()
on that address if the structure is not reset.

Fixes: d07c849cd2b9 ("net: ll_temac: Add more error handling of dma_map_single() calls")

Signed-off-by: Jonas Suhr Christensen <jsc@xxxxxxxxxxxxxx>
---
drivers/net/ethernet/xilinx/ll_temac_main.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c
index 74423adbe50d..df43f5bc3bd3 100644
--- a/drivers/net/ethernet/xilinx/ll_temac_main.c
+++ b/drivers/net/ethernet/xilinx/ll_temac_main.c
@@ -376,8 +376,11 @@ static int temac_dma_bd_init(struct net_device *ndev)
skb_dma_addr = dma_map_single(ndev->dev.parent, skb->data,
XTE_MAX_JUMBO_FRAME_SIZE,
DMA_FROM_DEVICE);
- if (dma_mapping_error(ndev->dev.parent, skb_dma_addr))
+ if (dma_mapping_error(ndev->dev.parent, skb_dma_addr)) {
+ dev_kfree_skb(lp->rx_skb[i]);
+ lp->rx_skb[i] = NULL;
goto out;
+ }
lp->rx_bd_v[i].phys = cpu_to_be32(skb_dma_addr);
lp->rx_bd_v[i].len = cpu_to_be32(XTE_MAX_JUMBO_FRAME_SIZE);
lp->rx_bd_v[i].app0 = cpu_to_be32(STS_CTRL_APP0_IRQONEND);
--
2.39.1