Replace NULL check with IS_ERR() check after calling page_pool_create()
since this function returns error pointers (ERR_PTR).
Using NULL check could lead to invalid pointer dereference.

Fixes: 8533b14b3d65 ("eth: mlx4: create a page pool for Rx")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
---
Changes in v2:
use err = PTR_ERR(ring->pp);
v1 link: https://lore.kernel.org/all/20250805025057.3659898-1-linmq006@gmail.com
---
 drivers/net/ethernet/mellanox/mlx4/en_rx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 92a16ddb7d86..13666d50b90f 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -267,8 +267,10 @@ int mlx4_en_create_rx_ring(struct mlx4_en_priv *priv,
    pp.dma_dir = priv->dma_dir;
 
    ring->pp = page_pool_create(&pp);
-   if (!ring->pp)
+   if (IS_ERR(ring->pp)) {
+       err = PTR_ERR(ring->pp);
        goto err_ring;
+   }
 
    if (xdp_rxq_info_reg(&ring->xdp_rxq, priv->dev, queue_index, 0) < 0)
        goto err_pp;
-- 
2.25.1

On Mon, 18 Aug 2025 00:38:30 +0800 Miaoqian Lin wrote:
> Replace NULL check with IS_ERR() check after calling page_pool_create()
> since this function returns error pointers (ERR_PTR).
> Using NULL check could lead to invalid pointer dereference.

The v2 patch is white-space corrupted. The v1 was fine, so maybe try to
send it the way you send the v1?
Please do *not* try to send the new version of the patch in reply to
the thread of v1. The link to v1 you put in the changelog is enough.
-- 
pw-bot: cr