From patchwork Wed Dec 7 10:52:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 13066972 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 403E4C6370D for ; Wed, 7 Dec 2022 10:53:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229804AbiLGKxS (ORCPT ); Wed, 7 Dec 2022 05:53:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229847AbiLGKwz (ORCPT ); Wed, 7 Dec 2022 05:52:55 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96A4A30F56 for ; Wed, 7 Dec 2022 02:52:50 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p2s2i-00074h-Rs for netdev@vger.kernel.org; Wed, 07 Dec 2022 11:52:48 +0100 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id B1B021387F4 for ; Wed, 7 Dec 2022 10:52:47 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id 88EBF1387CB; Wed, 7 Dec 2022 10:52:45 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id 0fa91cbf; Wed, 7 Dec 2022 10:52:44 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Oliver Hartkopp , syzbot+2d7f58292cb5b29eb5ad@syzkaller.appspotmail.com, Wei Chen , stable@vger.kernel.org, Marc Kleine-Budde Subject: [PATCH net 1/4] can: af_can: fix NULL pointer dereference in can_rcv_filter Date: Wed, 7 Dec 2022 11:52:40 +0100 Message-Id: <20221207105243.2483884-2-mkl@pengutronix.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221207105243.2483884-1-mkl@pengutronix.de> References: <20221207105243.2483884-1-mkl@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Oliver Hartkopp Analogue to commit 8aa59e355949 ("can: af_can: fix NULL pointer dereference in can_rx_register()") we need to check for a missing initialization of ml_priv in the receive path of CAN frames. Since commit 4e096a18867a ("net: introduce CAN specific pointer in the struct net_device") the check for dev->type to be ARPHRD_CAN is not sufficient anymore since bonding or tun netdevices claim to be CAN devices but do not initialize ml_priv accordingly. Fixes: 4e096a18867a ("net: introduce CAN specific pointer in the struct net_device") Reported-by: syzbot+2d7f58292cb5b29eb5ad@syzkaller.appspotmail.com Reported-by: Wei Chen Signed-off-by: Oliver Hartkopp Link: https://lore.kernel.org/all/20221206201259.3028-1-socketcan@hartkopp.net Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde --- net/can/af_can.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) base-commit: 1799c1b85e292fbfad99892bbea0beee925149e8 diff --git a/net/can/af_can.c b/net/can/af_can.c index 27dcdcc0b808..c69168f11e44 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -677,7 +677,7 @@ static void can_receive(struct sk_buff *skb, struct net_device *dev) static int can_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { - if (unlikely(dev->type != ARPHRD_CAN || (!can_is_can_skb(skb)))) { + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_can_skb(skb))) { pr_warn_once("PF_CAN: dropped non conform CAN skbuff: dev type %d, len %d\n", dev->type, skb->len); @@ -692,7 +692,7 @@ static int can_rcv(struct sk_buff *skb, struct net_device *dev, static int canfd_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { - if (unlikely(dev->type != ARPHRD_CAN || (!can_is_canfd_skb(skb)))) { + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_canfd_skb(skb))) { pr_warn_once("PF_CAN: dropped non conform CAN FD skbuff: dev type %d, len %d\n", dev->type, skb->len); @@ -707,7 +707,7 @@ static int canfd_rcv(struct sk_buff *skb, struct net_device *dev, static int canxl_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { - if (unlikely(dev->type != ARPHRD_CAN || (!can_is_canxl_skb(skb)))) { + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_canxl_skb(skb))) { pr_warn_once("PF_CAN: dropped non conform CAN XL skbuff: dev type %d, len %d\n", dev->type, skb->len); From patchwork Wed Dec 7 10:52:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 13066974 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8931FC63706 for ; Wed, 7 Dec 2022 10:53:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229619AbiLGKxT (ORCPT ); Wed, 7 Dec 2022 05:53:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43152 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229865AbiLGKwz (ORCPT ); Wed, 7 Dec 2022 05:52:55 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7C96D2F02D for ; Wed, 7 Dec 2022 02:52:51 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p2s2j-00077m-UB for netdev@vger.kernel.org; Wed, 07 Dec 2022 11:52:49 +0100 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id 0CDC21387FF for ; Wed, 7 Dec 2022 10:52:49 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id 9B69B1387CC; Wed, 7 Dec 2022 10:52:45 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id a55d57ee; Wed, 7 Dec 2022 10:52:44 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, "Jiri Slaby (SUSE)" , Richard Palethorpe , Petr Vorel , Dario Binacchi , Wolfgang Grandegger , Marc Kleine-Budde , Eric Dumazet , Paolo Abeni , stable@vger.kernel.org, Max Staudt Subject: [PATCH net 2/4] can: slcan: fix freed work crash Date: Wed, 7 Dec 2022 11:52:41 +0100 Message-Id: <20221207105243.2483884-3-mkl@pengutronix.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221207105243.2483884-1-mkl@pengutronix.de> References: <20221207105243.2483884-1-mkl@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: "Jiri Slaby (SUSE)" The LTP test pty03 is causing a crash in slcan: BUG: kernel NULL pointer dereference, address: 0000000000000008 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 348 Comm: kworker/0:3 Not tainted 6.0.8-1-default #1 openSUSE Tumbleweed 9d20364b934f5aab0a9bdf84e8f45cfdfae39dab Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014 Workqueue: 0x0 (events) RIP: 0010:process_one_work (/home/rich/kernel/linux/kernel/workqueue.c:706 /home/rich/kernel/linux/kernel/workqueue.c:2185) Code: 49 89 ff 41 56 41 55 41 54 55 53 48 89 f3 48 83 ec 10 48 8b 06 48 8b 6f 48 49 89 c4 45 30 e4 a8 04 b8 00 00 00 00 4c 0f 44 e0 <49> 8b 44 24 08 44 8b a8 00 01 00 00 41 83 e5 20 f6 45 10 04 75 0e RSP: 0018:ffffaf7b40f47e98 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff9d644e1b8b48 RCX: ffff9d649e439968 RDX: 00000000ffff8455 RSI: ffff9d644e1b8b48 RDI: ffff9d64764aa6c0 RBP: ffff9d649e4335c0 R08: 0000000000000c00 R09: ffff9d64764aa734 R10: 0000000000000007 R11: 0000000000000001 R12: 0000000000000000 R13: ffff9d649e4335e8 R14: ffff9d64490da780 R15: ffff9d64764aa6c0 FS: 0000000000000000(0000) GS:ffff9d649e400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 0000000036424000 CR4: 00000000000006f0 Call Trace: worker_thread (/home/rich/kernel/linux/kernel/workqueue.c:2436) kthread (/home/rich/kernel/linux/kernel/kthread.c:376) ret_from_fork (/home/rich/kernel/linux/arch/x86/entry/entry_64.S:312) Apparently, the slcan's tx_work is freed while being scheduled. While slcan_netdev_close() (netdev side) calls flush_work(&sl->tx_work), slcan_close() (tty side) does not. So when the netdev is never set UP, but the tty is stuffed with bytes and forced to wakeup write, the work is scheduled, but never flushed. So add an additional flush_work() to slcan_close() to be sure the work is flushed under all circumstances. The Fixes commit below moved flush_work() from slcan_close() to slcan_netdev_close(). What was the rationale behind it? Maybe we can drop the one in slcan_netdev_close()? I see the same pattern in can327. So it perhaps needs the very same fix. Fixes: cfcb4465e992 ("can: slcan: remove legacy infrastructure") Link: https://bugzilla.suse.com/show_bug.cgi?id=1205597 Reported-by: Richard Palethorpe Tested-by: Petr Vorel Cc: Dario Binacchi Cc: Wolfgang Grandegger Cc: Marc Kleine-Budde Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: linux-can@vger.kernel.org Cc: netdev@vger.kernel.org Cc: stable@vger.kernel.org Cc: Max Staudt Signed-off-by: Jiri Slaby (SUSE) Reviewed-by: Max Staudt Link: https://lore.kernel.org/all/20221201073426.17328-1-jirislaby@kernel.org Signed-off-by: Marc Kleine-Budde --- drivers/net/can/slcan/slcan-core.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/net/can/slcan/slcan-core.c b/drivers/net/can/slcan/slcan-core.c index fbb34139daa1..f4db77007c13 100644 --- a/drivers/net/can/slcan/slcan-core.c +++ b/drivers/net/can/slcan/slcan-core.c @@ -864,12 +864,14 @@ static void slcan_close(struct tty_struct *tty) { struct slcan *sl = (struct slcan *)tty->disc_data; - /* unregister_netdev() calls .ndo_stop() so we don't have to. - * Our .ndo_stop() also flushes the TTY write wakeup handler, - * so we can safely set sl->tty = NULL after this. - */ unregister_candev(sl->dev); + /* + * The netdev needn't be UP (so .ndo_stop() is not called). Hence make + * sure this is not running before freeing it up. + */ + flush_work(&sl->tx_work); + /* Mark channel as dead */ spin_lock_bh(&sl->lock); tty->disc_data = NULL; From patchwork Wed Dec 7 10:52:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 13066973 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D7B0AC4708E for ; Wed, 7 Dec 2022 10:53:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229845AbiLGKxT (ORCPT ); Wed, 7 Dec 2022 05:53:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229849AbiLGKwz (ORCPT ); Wed, 7 Dec 2022 05:52:55 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EFD0E31203 for ; Wed, 7 Dec 2022 02:52:50 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p2s2j-00075J-BL for netdev@vger.kernel.org; Wed, 07 Dec 2022 11:52:49 +0100 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id 67B5A1387FB for ; Wed, 7 Dec 2022 10:52:48 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id B303D1387CE; Wed, 7 Dec 2022 10:52:45 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id 7e3fed3b; Wed, 7 Dec 2022 10:52:44 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Max Staudt , "Jiri Slaby (SUSE)" , Wolfgang Grandegger , Marc Kleine-Budde , Eric Dumazet , Paolo Abeni , stable@vger.kernel.org Subject: [PATCH net 3/4] can: can327: flush TX_work on ldisc .close() Date: Wed, 7 Dec 2022 11:52:42 +0100 Message-Id: <20221207105243.2483884-4-mkl@pengutronix.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221207105243.2483884-1-mkl@pengutronix.de> References: <20221207105243.2483884-1-mkl@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Max Staudt Additionally, remove it from .ndo_stop(). This ensures that the worker is not called after being freed, and that the UART TX queue remains active to send final commands when the netdev is stopped. Thanks to Jiri Slaby for finding this in slcan: https://lore.kernel.org/linux-can/20221201073426.17328-1-jirislaby@kernel.org/ A variant of this patch for slcan, with the flush in .ndo_stop() still present, has been tested successfully on physical hardware: https://bugzilla.suse.com/show_bug.cgi?id=1205597 Fixes: 43da2f07622f ("can: can327: CAN/ldisc driver for ELM327 based OBD-II adapters") Cc: "Jiri Slaby (SUSE)" Cc: Max Staudt Cc: Wolfgang Grandegger Cc: Marc Kleine-Budde Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: linux-can@vger.kernel.org Cc: netdev@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Max Staudt Link: https://lore.kernel.org/all/20221202160148.282564-1-max@enpas.org Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde --- drivers/net/can/can327.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/net/can/can327.c b/drivers/net/can/can327.c index ed3d0b8989a0..dc7192ecb001 100644 --- a/drivers/net/can/can327.c +++ b/drivers/net/can/can327.c @@ -796,9 +796,9 @@ static int can327_netdev_close(struct net_device *dev) netif_stop_queue(dev); - /* Give UART one final chance to flush. */ - clear_bit(TTY_DO_WRITE_WAKEUP, &elm->tty->flags); - flush_work(&elm->tx_work); + /* We don't flush the UART TX queue here, as we want final stop + * commands (like the above dummy char) to be flushed out. + */ can_rx_offload_disable(&elm->offload); elm->can.state = CAN_STATE_STOPPED; @@ -1069,12 +1069,15 @@ static void can327_ldisc_close(struct tty_struct *tty) { struct can327 *elm = (struct can327 *)tty->disc_data; - /* unregister_netdev() calls .ndo_stop() so we don't have to. - * Our .ndo_stop() also flushes the TTY write wakeup handler, - * so we can safely set elm->tty = NULL after this. - */ + /* unregister_netdev() calls .ndo_stop() so we don't have to. */ unregister_candev(elm->dev); + /* Give UART one final chance to flush. + * No need to clear TTY_DO_WRITE_WAKEUP since .write_wakeup() is + * serialised against .close() and will not be called once we return. + */ + flush_work(&elm->tx_work); + /* Mark channel as dead */ spin_lock_bh(&elm->lock); tty->disc_data = NULL; From patchwork Wed Dec 7 10:52:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 13066970 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 076B0C63707 for ; Wed, 7 Dec 2022 10:53:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229489AbiLGKxP (ORCPT ); Wed, 7 Dec 2022 05:53:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43112 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229824AbiLGKwx (ORCPT ); Wed, 7 Dec 2022 05:52:53 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51C7B303F5 for ; Wed, 7 Dec 2022 02:52:50 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=bjornoya.blackshift.org) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1p2s2i-00074R-PH for netdev@vger.kernel.org; Wed, 07 Dec 2022 11:52:48 +0100 Received: from dspam.blackshift.org (localhost [127.0.0.1]) by bjornoya.blackshift.org (Postfix) with SMTP id 707511387EF for ; Wed, 7 Dec 2022 10:52:47 +0000 (UTC) Received: from hardanger.blackshift.org (unknown [172.20.34.65]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by bjornoya.blackshift.org (Postfix) with ESMTPS id C8C6F1387D0; Wed, 7 Dec 2022 10:52:45 +0000 (UTC) Received: from blackshift.org (localhost [::1]) by hardanger.blackshift.org (OpenSMTPD) with ESMTP id f38bb238; Wed, 7 Dec 2022 10:52:44 +0000 (UTC) From: Marc Kleine-Budde To: netdev@vger.kernel.org Cc: davem@davemloft.net, kuba@kernel.org, linux-can@vger.kernel.org, kernel@pengutronix.de, Frank Jungclaus , stable@vger.kernel.org, Marc Kleine-Budde Subject: [PATCH net 4/4] can: esd_usb: Allow REC and TEC to return to zero Date: Wed, 7 Dec 2022 11:52:43 +0100 Message-Id: <20221207105243.2483884-5-mkl@pengutronix.de> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221207105243.2483884-1-mkl@pengutronix.de> References: <20221207105243.2483884-1-mkl@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Frank Jungclaus We don't get any further EVENT from an esd CAN USB device for changes on REC or TEC while those counters converge to 0 (with ecc == 0). So when handling the "Back to Error Active"-event force txerr = rxerr = 0, otherwise the berr-counters might stay on values like 95 forever. Also, to make life easier during the ongoing development a netdev_dbg() has been introduced to allow dumping error events send by an esd CAN USB device. Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device") Signed-off-by: Frank Jungclaus Link: https://lore.kernel.org/all/20221130202242.3998219-2-frank.jungclaus@esd.eu Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde --- drivers/net/can/usb/esd_usb.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c index 81b88e9e5bdc..42323f5e6f3a 100644 --- a/drivers/net/can/usb/esd_usb.c +++ b/drivers/net/can/usb/esd_usb.c @@ -234,6 +234,10 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv, u8 rxerr = msg->msg.rx.data[2]; u8 txerr = msg->msg.rx.data[3]; + netdev_dbg(priv->netdev, + "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n", + msg->msg.rx.dlc, state, ecc, rxerr, txerr); + skb = alloc_can_err_skb(priv->netdev, &cf); if (skb == NULL) { stats->rx_dropped++; @@ -260,6 +264,8 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv, break; default: priv->can.state = CAN_STATE_ERROR_ACTIVE; + txerr = 0; + rxerr = 0; break; } } else {