net: ag71xx: Add missing check after DMA map

The DMA map functions can fail and should be tested for errors.

Signed-off-by: Thomas Fourier <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: Thomas-fourier

drivers/net/ethernet/atheros/ag71xx.c

@@ -1213,6 +1213,11 @@ static bool ag71xx_fill_rx_buf(struct ag71xx *ag, struct ag71xx_buf *buf,
 	buf->rx.rx_buf = data;
 	buf->rx.dma_addr = dma_map_single(&ag->pdev->dev, data, ag->rx_buf_size,
 					  DMA_FROM_DEVICE);
+	if (dma_mapping_error(&ag->pdev->dev, buf->rx.dma_addr)) {
+		skb_free_frag(data);
+		buf->rx.rx_buf = NULL;
+		return false;
+	}
 	desc->data = (u32)buf->rx.dma_addr + offset;
 	return true;
 }
@@ -1511,6 +1516,10 @@ static netdev_tx_t ag71xx_hard_start_xmit(struct sk_buff *skb,
 
 	dma_addr = dma_map_single(&ag->pdev->dev, skb->data, skb->len,
 				  DMA_TO_DEVICE);
+	if (dma_mapping_error(&ag->pdev->dev, dma_addr)) {
+		netif_dbg(ag, tx_err, ndev, "DMA mapping error\n");
+		goto err_drop;
+	}
 
 	i = ring->curr & ring_mask;
 	desc = ag71xx_ring_desc(ring, i);