From: Xuanqiang Luo The PTP clock is registered by ravb_open(), not ravb_probe(). Therefore, priv->ptp.clock is NULL between register_netdev() and the first open, and ethtool -T triggers a NULL dereference in ptp_clock_index(). ptp_clock_register() may also return an error pointer, which can reach ptp_clock_index() or ptp_clock_unregister(). Normalize registration errors to NULL and only query or unregister the clock when it is present. Leave phc_index at -1 when no PHC is registered, while preserving the static hardware timestamping capabilities. Fixes: a0d2f20650e8 ("Renesas Ethernet AVB PTP clock driver") Cc: stable@vger.kernel.org Signed-off-by: Xuanqiang Luo --- drivers/net/ethernet/renesas/ravb_main.c | 3 ++- drivers/net/ethernet/renesas/ravb_ptp.c | 12 ++++++++++-- 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 5f88733094d0f..3a9d9f8718216 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -1779,7 +1779,8 @@ static int ravb_get_ts_info(struct net_device *ndev, (1 << HWTSTAMP_FILTER_NONE) | (1 << HWTSTAMP_FILTER_PTP_V2_L2_EVENT) | (1 << HWTSTAMP_FILTER_ALL); - info->phc_index = ptp_clock_index(priv->ptp.clock); + if (priv->ptp.clock) + info->phc_index = ptp_clock_index(priv->ptp.clock); } return 0; diff --git a/drivers/net/ethernet/renesas/ravb_ptp.c b/drivers/net/ethernet/renesas/ravb_ptp.c index 226c6c0ab945b..eaf07cb8eadfa 100644 --- a/drivers/net/ethernet/renesas/ravb_ptp.c +++ b/drivers/net/ethernet/renesas/ravb_ptp.c @@ -315,6 +315,7 @@ void ravb_ptp_interrupt(struct net_device *ndev) void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) { struct ravb_private *priv = netdev_priv(ndev); + struct ptp_clock *clock; unsigned long flags; priv->ptp.info = ravb_ptp_info; @@ -327,7 +328,13 @@ void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) ravb_modify(ndev, GCCR, GCCR_TCSS, GCCR_TCSS_ADJGPTP); spin_unlock_irqrestore(&priv->lock, flags); - priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); + clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); + if (IS_ERR(clock)) { + netdev_err(ndev, "failed to register PTP clock: %pe\n", clock); + clock = NULL; + } + + priv->ptp.clock = clock; } void ravb_ptp_stop(struct net_device *ndev) @@ -337,5 +344,6 @@ void ravb_ptp_stop(struct net_device *ndev) ravb_write(ndev, 0, GIC); ravb_write(ndev, 0, GIS); - ptp_clock_unregister(priv->ptp.clock); + if (priv->ptp.clock) + ptp_clock_unregister(priv->ptp.clock); } -- 2.43.0