From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-172.mta0.migadu.com (out-172.mta0.migadu.com [91.218.175.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 01EC734A3BF for ; Tue, 11 Aug 2026 10:38:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786444714; cv=none; b=W4tdKn/qetXAltZM4gtr6uv4w9KY/xrAASmxsXrIlymzaNb7AIrpIIOWjGq4QP6g0571h3Os8fRslPigNmt9Xqg1FMPaOpmY8DMoHsah9PBLLe/Fqh2UVWBx2mxKAyJ0XeEl4LgymrfaKBYylBnq9oOVO4x9PVUlHpos0a3NdV4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786444714; c=relaxed/simple; bh=rYPdO/uorbeWDDLlHWLK3KcfyyUVKkDYDTmJMfZiT0Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RjLx/UogcD5Haw52zbfx6u9Th1TuyOwyjOlVKD0338yTBCTvlaRa5rdUg9istpmfpD1rjywG2Da4b72Vd2W29zLkVyd4Rx2qlNcQkuwEL2hAOPTB5Qnf8VflFdEooHqZwf0845vWtuqA5RkNhD1g5zmHyEw8Jp7AaGh3gdYNj5k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=w8Dvyzux; arc=none smtp.client-ip=91.218.175.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="w8Dvyzux" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1786444710; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3CMWQUutu+gMx2FwWWDdqi75E85hm8JL5dK++dM6XxY=; b=w8Dvyzux1/36PFKQDqjr/tB6rhCnxNxO2/RIRa4DusNUNEH8TRrGjjLNHt3U0lMCjBfR/e uMAvDLZ5cIALjWqBnx2zc023LbuZW1pOUItDbXaFvfA65htjamzSWRvQ2d5T+Ri2pOPqBY yf7+77360yDlmHq6FBBSnsHSz0vWx9Q= From: Xuanqiang Luo To: linux-renesas-soc@vger.kernel.org, netdev@vger.kernel.org, niklas.soderlund@ragnatech.se, kuba@kernel.org, vadim.fedorenko@linux.dev Cc: paul@pbarker.dev, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, richardcochran@gmail.com, masaru.nagai.vx@renesas.com, luoxuanqiang@kylinos.cn, stable@vger.kernel.org Subject: [PATCH net v4 1/2] net: ravb: avoid dereferencing an invalid PTP clock Date: Tue, 11 Aug 2026 18:37:32 +0800 Message-ID: <20260811103733.62599-2-xuanqiang.luo@linux.dev> In-Reply-To: <20260811103733.62599-1-xuanqiang.luo@linux.dev> References: <20260811103733.62599-1-xuanqiang.luo@linux.dev> Precedence: bulk X-Mailing-List: linux-renesas-soc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: Xuanqiang Luo 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: stable@vger.kernel.org Reviewed-by: Vadim Fedorenko Signed-off-by: Xuanqiang Luo --- 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