Commit 8169a601 authored by Yeounsu Moon's avatar Yeounsu Moon Committed by Jakub Kicinski
Browse files

net: dlink: handle copy_thresh allocation failure 



The driver did not handle failure of `netdev_alloc_skb_ip_align()`.
If the allocation failed, dereferencing `skb->protocol` could lead to
a NULL pointer dereference.

This patch tries to allocate `skb`. If the allocation fails, it falls
back to the normal path.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Suggested-by: default avatarJakub Kicinski <kuba@kernel.org>
Tested-on: D-Link DGE-550T Rev-A3
Signed-off-by: default avatarYeounsu Moon <yyyynoom@gmail.com>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20250928190124.1156-1-yyyynoom@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent f017156a

drivers/net/ethernet/dlink/dl2k.c

+5 −2
Original line number Diff line number Diff line
@@ -964,15 +964,18 @@ receive_packet (struct net_device *dev) 
		} else {

			struct sk_buff *skb;



			skb = NULL;

			/* Small skbuffs for short packets */

			if (pkt_len > copy_thresh) {

			if (pkt_len <= copy_thresh)

				skb = netdev_alloc_skb_ip_align(dev, pkt_len);

			if (!skb) {

				dma_unmap_single(&np->pdev->dev,

						 desc_to_dma(desc),

						 np->rx_buf_sz,

						 DMA_FROM_DEVICE);

				skb_put (skb = np->rx_skbuff[entry], pkt_len);

				np->rx_skbuff[entry] = NULL;

			} else if ((skb = netdev_alloc_skb_ip_align(dev, pkt_len))) {

			} else {

				dma_sync_single_for_cpu(&np->pdev->dev,

							desc_to_dma(desc),

							np->rx_buf_sz,