[PATCH 5.4 060/102] net: netsec: Correct dma sync for XDP_TX frames

[Greg Kroah-Hartman]

From: Ilias Apalodimas <ilias.apalodimas@xxxxxxxxxx>

[ Upstream commit d9496f3ecfe4823c1e12aecbcc29220147fa012c ]

bpf_xdp_adjust_head() can change the frame boundaries. Account for the
potential shift properly by calculating the new offset before
syncing the buffer to the device for XDP_TX

Fixes: ba2b232108d3 ("net: netsec: add XDP support")
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@xxxxxxxxxx>
Reviewed-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/ethernet/socionext/netsec.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/socionext/netsec.c b/drivers/net/ethernet/socionext/netsec.c
index f9e6744d8fd6e..41ddd8fff2a73 100644
--- a/drivers/net/ethernet/socionext/netsec.c
+++ b/drivers/net/ethernet/socionext/netsec.c
@@ -847,8 +847,8 @@ static u32 netsec_xdp_queue_one(struct netsec_priv *priv,
 		enum dma_data_direction dma_dir =
 			page_pool_get_dma_dir(rx_ring->page_pool);
 
-		dma_handle = page_pool_get_dma_addr(page) +
-			NETSEC_RXBUF_HEADROOM;
+		dma_handle = page_pool_get_dma_addr(page) + xdpf->headroom +
+			sizeof(*xdpf);
 		dma_sync_single_for_device(priv->dev, dma_handle, xdpf->len,
 					   dma_dir);
 		tx_desc.buf_type = TYPE_NETSEC_XDP_TX;
-- 
2.20.1