[PATCH 5.15 052/120] net: ethernet: nixge: fix NULL dereference

Greg Kroah-Hartman
2022-12-05T19:39:29Z

From: Yuri Karpov <YKarpov@ispras.ru>

[ Upstream commit 9256db4e45e8b497b0e993cc3ed4ad08eb2389b6 ]

In function nixge_hw_dma_bd_release() dereference of NULL pointer
priv->rx_bd_v is possible for the case of its allocation failure in
nixge_hw_dma_bd_init().

Move for() loop with priv->rx_bd_v dereference under the check for
its validity.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 492caffa8a1a ("net: ethernet: nixge: Add support for National Instruments XGE netdev")
Signed-off-by: Yuri Karpov <YKarpov@ispras.ru>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/ni/nixge.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/ni/nixge.c b/drivers/net/ethernet/ni/nixge.c
index 057b7419404d..5d0cecf80b38 100644
--- a/drivers/net/ethernet/ni/nixge.c
+++ b/drivers/net/ethernet/ni/nixge.c
@@ -249,25 +249,26 @@ static void nixge_hw_dma_bd_release(struct net_device *ndev)
struct sk_buff *skb;
int i;

- for (i = 0; i < RX_BD_NUM; i++) {
- phys_addr = nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[i],
- phys);
-
- dma_unmap_single(ndev->dev.parent, phys_addr,
- NIXGE_MAX_JUMBO_FRAME_SIZE,
- DMA_FROM_DEVICE);
-
- skb = (struct sk_buff *)(uintptr_t)
- nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[i],
- sw_id_offset);
- dev_kfree_skb(skb);
- }
+ if (priv->rx_bd_v) {
+ for (i = 0; i < RX_BD_NUM; i++) {
+ phys_addr = nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[i],
+ phys);
+
+ dma_unmap_single(ndev->dev.parent, phys_addr,
+ NIXGE_MAX_JUMBO_FRAME_SIZE,
+ DMA_FROM_DEVICE);
+
+ skb = (struct sk_buff *)(uintptr_t)
+ nixge_hw_dma_bd_get_addr(&priv->rx_bd_v[i],
+ sw_id_offset);
+ dev_kfree_skb(skb);
+ }

- if (priv->rx_bd_v)
dma_free_coherent(ndev->dev.parent,
sizeof(*priv->rx_bd_v) * RX_BD_NUM,
priv->rx_bd_v,
priv->rx_bd_p);
+ }

if (priv->tx_skb)
devm_kfree(ndev->dev.parent, priv->tx_skb);
--
2.35.1