From 40e0d0746390c5b0c31144f4f1688d72f3f8d790 Mon Sep 17 00:00:00 2001 From: Rahul Rameshbabu Date: Wed, 22 Nov 2023 18:32:11 -0800 Subject: [PATCH] net/mlx5e: Fix operation precedence bug in port timestamping napi_poll context [ Upstream commit 3876638b2c7ebb2c9d181de1191db0de8cac143a ] Indirection (*) is of lower precedence than postfix increment (++). Logic in napi_poll context would cause an out-of-bound read by first increment the pointer address by byte address space and then dereference the value. Rather, the intended logic was to dereference first and then increment the underlying value. Fixes: 92214be5979c ("net/mlx5e: Update doorbell for port timestamping CQ before the software counter") Signed-off-by: Rahul Rameshbabu Reviewed-by: Tariq Toukan Signed-off-by: Saeed Mahameed Signed-off-by: Sasha Levin --- 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 af3928e..803035d 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c @@ -213,7 +213,7 @@ static void mlx5e_ptp_handle_ts_cqe(struct mlx5e_ptpsq *ptpsq, mlx5e_ptpsq_mark_ts_cqes_undelivered(ptpsq, hwtstamp); out: napi_consume_skb(skb, budget); - md_buff[*md_buff_sz++] = metadata_id; + md_buff[(*md_buff_sz)++] = metadata_id; if (unlikely(mlx5e_ptp_metadata_map_unhealthy(&ptpsq->metadata_map)) && !test_and_set_bit(MLX5E_SQ_STATE_RECOVERING, &sq->state)) queue_work(ptpsq->txqsq.priv->wq, &ptpsq->report_unhealthy_work); -- 2.7.4