[PATCH 4.9 063/105] net: qcom/emac: specify the correct size when mapping a DMA buffer

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Timur Tabi <timur@xxxxxxxxxxxxxx>


[ Upstream commit a93ad944f4ff9a797abff17c73fc4b1e4a1d9141 ]

When mapping the RX DMA buffers, the driver was accidentally specifying
zero for the buffer length.  Under normal circumstances, SWIOTLB does not
need to allocate a bounce buffer, so the address is just mapped without
checking the size field.  This is why the error was not detected earlier.

Fixes: b9b17debc69d ("net: emac: emac gigabit ethernet controller driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Timur Tabi <timur@xxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/qualcomm/emac/emac-mac.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/qualcomm/emac/emac-mac.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-mac.c
@@ -932,7 +932,8 @@ static void emac_mac_rx_descs_refill(str
 
 		curr_rxbuf->dma_addr =
 			dma_map_single(adpt->netdev->dev.parent, skb->data,
-				       curr_rxbuf->length, DMA_FROM_DEVICE);
+				       adpt->rxbuf_size, DMA_FROM_DEVICE);
+
 		ret = dma_mapping_error(adpt->netdev->dev.parent,
 					curr_rxbuf->dma_addr);
 		if (ret) {