From mboxrd@z Thu Jan 1 00:00:00 1970 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 2F1F2C433EF for ; Mon, 21 Mar 2022 01:48:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343763AbiCUBtc (ORCPT ); Sun, 20 Mar 2022 21:49:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344077AbiCUBtb (ORCPT ); Sun, 20 Mar 2022 21:49:31 -0400 Received: from mail-pj1-x1043.google.com (mail-pj1-x1043.google.com [IPv6:2607:f8b0:4864:20::1043]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D48C233E27; Sun, 20 Mar 2022 18:48:05 -0700 (PDT) Received: by mail-pj1-x1043.google.com with SMTP id o68-20020a17090a0a4a00b001c686a48263so6591659pjo.1; Sun, 20 Mar 2022 18:48:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=MXaHjSqW1X8Va2iXmuY0GdSIMSz0sws/QMoV4WVeEt8=; b=bXw8LgDE+o11taz8NT95gJXNCd0JYnAVosKlZ3yFvjmLg4jhiTCWKd4sVOsYzNyMiI E5W3oHErXcbJ1uLYklqrhWXpDnrKsGsJ86cZ/D9THR6l11pkUeHqWULGsoYipq1Q8Aug YaO66Ox26YrcTvAk/VxszYXDHxdoENQC7D4s+y9H+//iYhOhv5rpdSDqyMCVbDtY1wgJ y/tABDaGrswWJZ59x9Df5+1b9Nuo7Hr1Rqsr5/DZSvybQAgQldym+nQFev4VJbkISgGR 9cqyfmYHh0ogOifKOY2WbpNfXr3+Yw3uHpz5vLKtlYDaWnEjPJCSDccMHKKYjotvd8rj pQug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=MXaHjSqW1X8Va2iXmuY0GdSIMSz0sws/QMoV4WVeEt8=; b=wY0n0t4a8WpdqKxtVyT4dsN7/3gPZ1EqnIDxZcIvCGRx4TbkdYKwbJ9OWYe5/kzf4l bLNSiWwlYWg8mEB79HjyjDquBZ1avo7iVRB+z98PmUlK7iipKrSyG3pi6w4aY2suZlQn AN0pa75yaxKjpELuMNoZpX+4oML/5wWJcDIxpISBojD9GKXSUME7x6dlMHb7UATIbjbu thwIo8L39v9I3aXJ6muc26kxKYP0Wr5ybwj5PToeYnQl1qla3HM+ASVD0Q75sJZFBJ9+ 4a9705sE+R/Sxe2Q0AIeIkhUUj3J56QSP1xvf/ByWsrdpwMPvbNFDr9zIwY99k65MhBc Rd4w== X-Gm-Message-State: AOAM533e8VDSUNPOtTgP7gX1+DOoT43gh+EV4Uu+i1nHdaskcd7gOEcG /XfX+wiMMVQmgUxTKMsNYdXcA+iZT+jXTw== X-Google-Smtp-Source: ABdhPJzwqjSayPfEdLMbnZ9hl+6ggCJT03NPCSGkybxAu1cj53SWeZ32/CQmZb6HD69avg0sPg8YnQ== X-Received: by 2002:a17:903:1205:b0:151:8ae9:93ea with SMTP id l5-20020a170903120500b001518ae993eamr10752168plh.37.1647827285428; Sun, 20 Mar 2022 18:48:05 -0700 (PDT) Received: from [10.11.37.162] ([103.84.139.53]) by smtp.gmail.com with ESMTPSA id h2-20020a056a00218200b004f6519ce666sm17329005pfi.170.2022.03.20.18.48.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 20 Mar 2022 18:48:05 -0700 (PDT) Message-ID: Date: Mon, 21 Mar 2022 09:47:58 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH] can: usb_8dev: fix possible double dev_kfree_skb in usb_8dev_start_xmit Content-Language: en-US To: wg@grandegger.com, mkl@pengutronix.de, davem@davemloft.net, kuba@kernel.org, stefan.maetje@esd.eu, mailhol.vincent@wanadoo.fr, paskripkin@gmail.com, b.krumboeck@gmail.com Cc: linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220311080614.45229-1-hbh25y@gmail.com> From: Hangyu Hua In-Reply-To: <20220311080614.45229-1-hbh25y@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org Gentle ping. On 2022/3/11 16:06, Hangyu Hua wrote: > There is no need to call dev_kfree_skb when usb_submit_urb fails beacause > can_put_echo_skb deletes original skb and can_free_echo_skb deletes the cloned > skb. > > Fixes: 0024d8ad1639 ("can: usb_8dev: Add support for USB2CAN interface from 8 devices") > Signed-off-by: Hangyu Hua > --- > drivers/net/can/usb/usb_8dev.c | 30 ++++++++++++++---------------- > 1 file changed, 14 insertions(+), 16 deletions(-) > > diff --git a/drivers/net/can/usb/usb_8dev.c b/drivers/net/can/usb/usb_8dev.c > index 431af1ec1e3c..b638604bf1ee 100644 > --- a/drivers/net/can/usb/usb_8dev.c > +++ b/drivers/net/can/usb/usb_8dev.c > @@ -663,9 +663,20 @@ static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb, > atomic_inc(&priv->active_tx_urbs); > > err = usb_submit_urb(urb, GFP_ATOMIC); > - if (unlikely(err)) > - goto failed; > - else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS) > + if (unlikely(err)) { > + can_free_echo_skb(netdev, context->echo_index, NULL); > + > + usb_unanchor_urb(urb); > + usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); > + > + atomic_dec(&priv->active_tx_urbs); > + > + if (err == -ENODEV) > + netif_device_detach(netdev); > + else > + netdev_warn(netdev, "failed tx_urb %d\n", err); > + stats->tx_dropped++; > + } else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS) > /* Slow down tx path */ > netif_stop_queue(netdev); > > @@ -684,19 +695,6 @@ static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb, > > return NETDEV_TX_BUSY; > > -failed: > - can_free_echo_skb(netdev, context->echo_index, NULL); > - > - usb_unanchor_urb(urb); > - usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); > - > - atomic_dec(&priv->active_tx_urbs); > - > - if (err == -ENODEV) > - netif_device_detach(netdev); > - else > - netdev_warn(netdev, "failed tx_urb %d\n", err); > - > nomembuf: > usb_free_urb(urb); >