[PATCH 5.17 0824/1126] net: sparx5: switchdev: fix possible NULL pointer dereference

Greg Kroah-Hartman
2022-04-05T08:35:50Z

From: Zheng Yongjun <zhengyongjun3@huawei.com>

[ Upstream commit 0906f3a3df07835e37077d8971aac65347f2ed57 ]

As the possible failure of the allocation, devm_kzalloc() may return NULL
pointer.
Therefore, it should be better to check the 'db' in order to prevent
the dereference of NULL pointer.

Fixes: 10615907e9b51 ("net: sparx5: switchdev: adding frame DMA functionality")
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c b/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c
index 7436f62fa152..174ad95e746a 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c
@@ -420,6 +420,8 @@ static int sparx5_fdma_tx_alloc(struct sparx5 *sparx5)
db_hw->dataptr = phys;
db_hw->status = 0;
db = devm_kzalloc(sparx5->dev, sizeof(*db), GFP_KERNEL);
+ if (!db)
+ return -ENOMEM;
db->cpu_addr = cpu_addr;
list_add_tail(&db->list, &tx->db_list);
}
--
2.34.1