[PATCH net v4 1/2] net: ravb: avoid dereferencing an invalid PTP clock
Xuanqiang Luo <[email protected]>
| Newsgroups | org.kernel.vger.netdev,org.kernel.vger.linux-renesas-soc,org.kernel.vger.stable |
|---|---|
| Message-ID | <[email protected]> |
From: Xuanqiang Luo <[email protected]> The PTP clock is unavailable before the first open, so querying its index can dereference a NULL pointer. Registration failures can also leave an error pointer in priv->ptp.clock. Cache the PHC index separately and report -1 while no clock is registered. Normalize registration errors to NULL and preserve the static timestamping capabilities. Fixes: a0d2f20650e8 ("Renesas Ethernet AVB PTP clock driver") Cc: [email protected] Reviewed-by: Vadim Fedorenko <[email protected]> Signed-off-by: Xuanqiang Luo <[email protected]> --- drivers/net/ethernet/renesas/ravb.h | 1 + drivers/net/ethernet/renesas/ravb_main.c | 3 ++- drivers/net/ethernet/renesas/ravb_ptp.c | 15 +++++++++++++-- 3 files changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h index 5e56ec9b1013a..2a4fcb12a63cb 100644 --- a/drivers/net/ethernet/renesas/ravb.h +++ b/drivers/net/ethernet/renesas/ravb.h @@ -1028,6 +1028,7 @@ struct ravb_ptp_perout { struct ravb_ptp { struct ptp_clock *clock; struct ptp_clock_info info; + int phc_index; u32 default_addend; u32 current_addend; int extts[N_EXT_TS]; diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c index 5f88733094d0f..db0229e008494 100644 --- a/drivers/net/ethernet/renesas/ravb_main.c +++ b/drivers/net/ethernet/renesas/ravb_main.c @@ -1779,7 +1779,7 @@ 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); + info->phc_index = READ_ONCE(priv->ptp.phc_index); } return 0; @@ -2953,6 +2953,7 @@ static int ravb_probe(struct platform_device *pdev) priv->rstc = rstc; priv->ndev = ndev; priv->pdev = pdev; + priv->ptp.phc_index = -1; priv->num_tx_ring[RAVB_BE] = BE_TX_RING_SIZE; priv->num_rx_ring[RAVB_BE] = BE_RX_RING_SIZE; if (info->nc_queues) { diff --git a/drivers/net/ethernet/renesas/ravb_ptp.c b/drivers/net/ethernet/renesas/ravb_ptp.c index 226c6c0ab945b..cbec7c057d715 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 +328,15 @@ 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; + if (clock) + WRITE_ONCE(priv->ptp.phc_index, ptp_clock_index(clock)); } void ravb_ptp_stop(struct net_device *ndev) @@ -337,5 +346,7 @@ void ravb_ptp_stop(struct net_device *ndev) ravb_write(ndev, 0, GIC); ravb_write(ndev, 0, GIS); - ptp_clock_unregister(priv->ptp.clock); + WRITE_ONCE(priv->ptp.phc_index, -1); + if (priv->ptp.clock) + ptp_clock_unregister(priv->ptp.clock); } -- 2.43.0