[PATCH net v2 2/2] net: dlink: handle copy_thresh allocation failure
From: Yeounsu Moon <hidden>
Date: 2025-09-14 18:31:40
Also in:
lkml
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
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 adds proper error handling by falling back to the `else` clause
when the allocation fails.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Tested-on: D-Link DGE-550T Rev-A3
Signed-off-by: Yeounsu Moon <redacted>
---
drivers/net/ethernet/dlink/dl2k.c | 21 +++++++++++++--------
1 file changed, 13 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ethernet/dlink/dl2k.c b/drivers/net/ethernet/dlink/dl2k.c
index faf8a9fc7ed1..a82e1fd01b92 100644
--- a/drivers/net/ethernet/dlink/dl2k.c
+++ b/drivers/net/ethernet/dlink/dl2k.c@@ -965,14 +965,11 @@ receive_packet (struct net_device *dev) struct sk_buff *skb; /* Small skbuffs for short packets */ - if (pkt_len > copy_thresh) { - 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))) { + if (pkt_len <= copy_thresh) { + skb = netdev_alloc_skb_ip_align(dev, pkt_len); + if (!skb) + goto reuse_skbuff; + dma_sync_single_for_cpu(&np->pdev->dev, desc_to_dma(desc), np->rx_buf_sz,
@@ -985,6 +982,14 @@ receive_packet (struct net_device *dev) desc_to_dma(desc), np->rx_buf_sz, DMA_FROM_DEVICE); + } else { +reuse_skbuff: + 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; } skb->protocol = eth_type_trans (skb, dev); #if 0
--
2.51.0