From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 022BE1F92C; Mon, 4 Mar 2024 21:37:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709588279; cv=none; b=vFb+zE9wAxbYd6P2ZFqCrXYXLAyBO7Mm4VW2EuIMVZxO6tfUqVUwQxE4XSAUOoLDwFB31oZPNpFU6q2II3hCsHTu5yFUcRdXNZiKgHjeASWQ0wpMb/X0Q0gwqy6mL8MmUfq8kLpia83CIzCWR41QK51lkcvPRJfpDOWLRfVruu4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709588279; c=relaxed/simple; bh=cAO6AriFR2ac9ZnAB03NB7ku6223KcrVG5OrZlkAPcA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kaBhlDhmIeJ/aLotIw4hRZq5JntWZSQEJRYhlT5I55tdHQ0t0noh4h/YnBDjWBLN7AUVMdjRaLEhAPVcP/FLHgvlA5ZlJBwf5SqpJYYeEn/YLUjOKlCOhfHJzoCbXH3CIBwWeXgrewNeM60QHVajiuBQ7UwPzYSysUbyA/WM770= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=F+lAUcoq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="F+lAUcoq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A546C433F1; Mon, 4 Mar 2024 21:37:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1709588278; bh=cAO6AriFR2ac9ZnAB03NB7ku6223KcrVG5OrZlkAPcA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=F+lAUcoqZFpn9E0D637cIrbjKL/Gu9XOJ0SNdDuLyr2qDAC6h6vtJhlnpbxVCdAGA kEpFEU0xEJ98/T/oV4syrqZhHZmU7y13mDgWJkkOQeNvQYhKMhk0bJ9/X9SXR+tpxW PxTwTz1Zav4AAsW5wu/r73AvHQxKCwOwfvIiMakw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jakub Raczynski , Jiri Pirko , "David S. Miller" , Sasha Levin Subject: [PATCH 6.6 022/143] stmmac: Clear variable when destroying workqueue Date: Mon, 4 Mar 2024 21:22:22 +0000 Message-ID: <20240304211550.650087184@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240304211549.876981797@linuxfoundation.org> References: <20240304211549.876981797@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jakub Raczynski [ Upstream commit 8af411bbba1f457c33734795f024d0ef26d0963f ] Currently when suspending driver and stopping workqueue it is checked whether workqueue is not NULL and if so, it is destroyed. Function destroy_workqueue() does drain queue and does clear variable, but it does not set workqueue variable to NULL. This can cause kernel/module panic if code attempts to clear workqueue that was not initialized. This scenario is possible when resuming suspended driver in stmmac_resume(), because there is no handling for failed stmmac_hw_setup(), which can fail and return if DMA engine has failed to initialize, and workqueue is initialized after DMA engine. Should DMA engine fail to initialize, resume will proceed normally, but interface won't work and TX queue will eventually timeout, causing 'Reset adapter' error. This then does destroy workqueue during reset process. And since workqueue is initialized after DMA engine and can be skipped, it will cause kernel/module panic. To secure against this possible crash, set workqueue variable to NULL when destroying workqueue. Log/backtrace from crash goes as follows: [88.031977]------------[ cut here ]------------ [88.031985]NETDEV WATCHDOG: eth0 (sxgmac): transmit queue 1 timed out [88.032017]WARNING: CPU: 0 PID: 0 at net/sched/sch_generic.c:477 dev_watchdog+0x390/0x398 [88.032251]---[ end trace e70de432e4d5c2c0 ]--- [88.032282]sxgmac 16d88000.ethernet eth0: Reset adapter. [88.036359]------------[ cut here ]------------ [88.036519]Call trace: [88.036523] flush_workqueue+0x3e4/0x430 [88.036528] drain_workqueue+0xc4/0x160 [88.036533] destroy_workqueue+0x40/0x270 [88.036537] stmmac_fpe_stop_wq+0x4c/0x70 [88.036541] stmmac_release+0x278/0x280 [88.036546] __dev_close_many+0xcc/0x158 [88.036551] dev_close_many+0xbc/0x190 [88.036555] dev_close.part.0+0x70/0xc0 [88.036560] dev_close+0x24/0x30 [88.036564] stmmac_service_task+0x110/0x140 [88.036569] process_one_work+0x1d8/0x4a0 [88.036573] worker_thread+0x54/0x408 [88.036578] kthread+0x164/0x170 [88.036583] ret_from_fork+0x10/0x20 [88.036588]---[ end trace e70de432e4d5c2c1 ]--- [88.036597]Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 Fixes: 5a5586112b929 ("net: stmmac: support FPE link partner hand-shaking procedure") Signed-off-by: Jakub Raczynski Reviewed-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 5b3423d1af3f3..d1adb102a1d49 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -3926,8 +3926,10 @@ static void stmmac_fpe_stop_wq(struct stmmac_priv *priv) { set_bit(__FPE_REMOVING, &priv->fpe_task_state); - if (priv->fpe_wq) + if (priv->fpe_wq) { destroy_workqueue(priv->fpe_wq); + priv->fpe_wq = NULL; + } netdev_info(priv->dev, "FPE workqueue stop"); } -- 2.43.0