Re: [PATCH net] net/mlx5e: Fix NULL deref in PTP TX timestamp recovery warn

[Vadim Fedorenko <vadim.fedorenko@linux.dev>]

On 15/10/2026 09:02, Tariq Toukan wrote:
> From: Carolina Jubran <cjubran@nvidia.com>
> 
> PTP SQs are allocated via mlx5e_ptp_alloc_txqsq(), which never sets
> sq->channel. The excessive port timestamp delta recovery path
> incorrectly used sq->channel->netdev for netdev_warn(), causing a NULL
> pointer dereference. Use sq->netdev instead.
> 
> Fixes: 391dad2e686f ("net/mlx5e: Recover SQ on excessive PTP TX timestamp delta")
> Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
> Reviewed-by: Alex Lazar <alazar@nvidia.com>
> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
> ---
>   drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c
> index 723f66a6bd63..2e1c3bb5a959 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c
> @@ -98,7 +98,7 @@ static void mlx5e_skb_cb_hwtstamp_tx(struct sk_buff *skb,
>   		ptpsq->cq_stats->abort_abs_diff_ns += diff;
>   		if (diff > (NSEC_PER_SEC >> 1) &&
>   		    !test_and_set_bit(MLX5E_SQ_STATE_RECOVERING, &sq->state)) {
> -			netdev_warn(sq->channel->netdev,
> +			netdev_warn(sq->netdev,
>   				    "PTP TX timestamp difference between CQE and port exceeds threshold: %lld ns, recovering SQ %u\n",
>   				    (s64)diff, sq->sqn);
>   			queue_work(sq->priv->wq, &ptpsq->report_unhealthy_work);
> 
> base-commit: 513444cc62e231a11c9b15ea88de0890da9b2b4f

Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>