[PATCH] net/mlx5: Fix potential NULL dereference in PTP event handling

Prathamesh Deshpande
2026-03-31T15:32:49Z

In mlx5_ptp_pps_event(), a TODO comment correctly identified that
clock->ptp can be NULL if ptp_clock_register() fails. However, the
code proceeded to call ptp_clock_event() with that NULL pointer,
leading to a potential kernel panic.

Fix this by adding a NULL check for clock->ptp before calling
ptp_clock_event(), ensuring the driver handles failed registration
gracefully.

Fixes: 7c39afb394c7 ("net/mlx5: PTP code migration to driver core section")

Signed-off-by: Prathamesh Deshpande <prathameshdeshpande7@gmail.com>
---
drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
index bd4e042077af..9e9f844935b4 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
@@ -1185,8 +1185,8 @@ static int mlx5_pps_event(struct notifier_block *nb,
} else {
ptp_event.type = PTP_CLOCK_EXTTS;
}
- /* TODOL clock->ptp can be NULL if ptp_clock_register fails */
- ptp_clock_event(clock->ptp, &ptp_event);
+ if (clock->ptp)
+ ptp_clock_event(clock->ptp, &ptp_event);
break;
case PTP_PF_PEROUT:
if (clock->shared) {
--
2.43.0