From 7b97273cbebe9dd4fddc457f0c4f2a124d0e3996 Mon Sep 17 00:00:00 2001 From: Prathamesh Deshpande Date: Sat, 26 Sep 2026 17:53:57 +0100 Subject: [PATCH] net/mlx5e: Fix AF_XDP TX timestamp teardown NULL dereference During XSK TX queue teardown, outstanding descriptors are completed without a CQE. If one requested a TX timestamp, the completion path passes that NULL CQE to mlx5e_xsk_fill_timestamp(), which dereferences it. Return zero when no CQE is available, indicating that teardown did not produce a TX timestamp. Fixes: ec706a860eba ("net/mlx5e: Implement AF_XDP TX timestamp and checksum offload") Signed-off-by: Prathamesh Deshpande Reviewed-by: Tariq Toukan Link: https://patch.msgid.link/20260926165402.5902-1-prathameshdeshpande7@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c index 77ea51bfbaae..2cca20e1b9b7 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c @@ -293,6 +293,9 @@ static u64 mlx5e_xsk_fill_timestamp(void *_priv) struct mlx5e_xsk_tx_complete *priv = _priv; u64 ts; + if (!priv->cqe) + return 0; + ts = get_cqe_ts(priv->cqe); if (mlx5_is_real_time_rq(priv->cq->mdev) || mlx5_is_real_time_sq(priv->cq->mdev))