Commit 19e72b06 authored by Wei Fang's avatar Wei Fang Committed by Jakub Kicinski
Browse files

net: fec: check the return value of build_skb() 



The build_skb might return a null pointer but there is no check on the
return value in the fec_enet_rx_queue(). So a null pointer dereference
might occur. To avoid this, we check the return value of build_skb. If
the return value is a null pointer, the driver will recycle the page and
update the statistic of ndev. Then jump to rx_processing_done to clear
the status flags of the BD so that the hardware can recycle the BD.

Fixes: 95698ff6 ("net: fec: using page pool to manage RX buffers")
Signed-off-by: default avatarWei Fang <wei.fang@nxp.com>
Reviewed-by: default avatarShenwei Wang <Shenwei.wang@nxp.com>
Reviewed-by: default avatarAlexander Duyck <alexanderduyck@fb.com>
Link: https://lore.kernel.org/r/20221219022755.1047573-1-wei.fang@nxp.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 4be84df3

drivers/net/ethernet/freescale/fec_main.c

+8 −0
Original line number Diff line number Diff line
@@ -1674,6 +1674,14 @@ fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id) 
		 * bridging applications.

		 */

		skb = build_skb(page_address(page), PAGE_SIZE);

		if (unlikely(!skb)) {

			page_pool_recycle_direct(rxq->page_pool, page);

			ndev->stats.rx_dropped++;



			netdev_err_once(ndev, "build_skb failed!\n");

			goto rx_processing_done;

		}



		skb_reserve(skb, data_start);

		skb_put(skb, pkt_len - sub_len);

		skb_mark_for_recycle(skb);