[PATCH 5.9 002/252] atm: nicstar: Unmap DMA on send error

From: Greg Kroah-Hartman
Date: Mon Nov 23 2020 - 07:43:04 EST


From: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>

[ Upstream commit 6dceaa9f56e22d0f9b4c4ad2ed9e04e315ce7fe5 ]

The `skb' is mapped for DMA in ns_send() but does not unmap DMA in case
push_scqe() fails to submit the `skb'. The memory of the `skb' is
released so only the DMA mapping is leaking.

Unmap the DMA mapping in case push_scqe() failed.

Fixes: 864a3ff635fa7 ("atm: [nicstar] remove virt_to_bus() and support 64-bit platforms")
Cc: Chas Williams <3chas3@xxxxxxxxx>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/atm/nicstar.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/atm/nicstar.c
+++ b/drivers/atm/nicstar.c
@@ -1706,6 +1706,8 @@ static int ns_send(struct atm_vcc *vcc,

if (push_scqe(card, vc, scq, &scqe, skb) != 0) {
atomic_inc(&vcc->stats->tx_err);
+ dma_unmap_single(&card->pcidev->dev, NS_PRV_DMA(skb), skb->len,
+ DMA_TO_DEVICE);
dev_kfree_skb_any(skb);
return -EIO;
}