[PATCH 5.18 525/879] dpaa2-eth: unmap the SGT buffer before accessing its contents

Greg Kroah-Hartman
2022-06-08T01:31:10Z

From: Ioana Ciornei <ioana.ciornei@nxp.com>

[ Upstream commit 0a09c5b8cb8f75344da7d90c771b84f7cdeaea04 ]

DMA unmap the Scatter/Gather table before going through the array to
unmap and free each of the header and data chunks. This is so we do not
touch the data between the dma_map and dma_unmap calls.

Fixes: 3dc709e0cd47 ("dpaa2-eth: add support for software TSO")
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
index f1f140277184..cd9ec80522e7 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
@@ -1136,6 +1136,10 @@ static void dpaa2_eth_free_tx_fd(struct dpaa2_eth_priv *priv,
sgt = (struct dpaa2_sg_entry *)(buffer_start +
priv->tx_data_offset);

+ /* Unmap the SGT buffer */
+ dma_unmap_single(dev, fd_addr, swa->tso.sgt_size,
+ DMA_BIDIRECTIONAL);
+
/* Unmap and free the header */
tso_hdr = dpaa2_iova_to_virt(priv->iommu_domain, dpaa2_sg_get_addr(sgt));
dma_unmap_single(dev, dpaa2_sg_get_addr(sgt), TSO_HEADER_SIZE,
@@ -1147,10 +1151,6 @@ static void dpaa2_eth_free_tx_fd(struct dpaa2_eth_priv *priv,
dma_unmap_single(dev, dpaa2_sg_get_addr(&sgt[i]),
dpaa2_sg_get_len(&sgt[i]), DMA_TO_DEVICE);

- /* Unmap the SGT buffer */
- dma_unmap_single(dev, fd_addr, swa->tso.sgt_size,
- DMA_BIDIRECTIONAL);
-
if (!swa->tso.is_last_fd)
should_free_skb = 0;
} else {
--
2.35.1