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Message-ID: <340590e9-2150-cd6e-5333-21c4fde59e98@gmail.com>
Date:   Mon, 28 Feb 2022 16:06:07 +0800
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Subject: Re: [PATCH] can: usb: fix a possible memory leak in
 esd_usb2_start_xmit
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To:     Marc Kleine-Budde <mkl@pengutronix.de>
Cc:     wg@grandegger.com, davem@davemloft.net, kuba@kernel.org,
        stefan.maetje@esd.eu, mailhol.vincent@wanadoo.fr,
        paskripkin@gmail.com, thunder.leizhen@huawei.com,
        linux-can@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20220225060019.21220-1-hbh25y@gmail.com>
 <20220225155621.7zmfukra63qcxjo5@pengutronix.de>
 <69b0dd44-93ac-fa33-f9c1-6f787185ab47@gmail.com>
 <20220228075146.hvui3iow7niupij4@pengutronix.de>
From:   Hangyu Hua <hbh25y@gmail.com>
In-Reply-To: <20220228075146.hvui3iow7niupij4@pengutronix.de>
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Yes. I will create a patch later.

Thanks.

On 2022/2/28 15:51, Marc Kleine-Budde wrote:
> On 28.02.2022 10:05:03, Hangyu Hua wrote:
>> I get it. But this means ems_usb_start_xmit have a redundant
>> dev_kfree_skb beacause can_put_echo_skb delete original skb and
>> can_free_echo_skb delete the cloned skb. While this code is harmless
>> do you think we need to delete it ?
> 
> ACK. This dev_kfree_skb() should be deleted:
> 
> | 	err = usb_submit_urb(urb, GFP_ATOMIC);
> | 	if (unlikely(err)) {
> | 		can_free_echo_skb(netdev, context->echo_index, NULL);
> |
> | 		usb_unanchor_urb(urb);
> | 		usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
> | 		dev_kfree_skb(skb);
> 
> Can you create a patch?
> 
> regards,
> Marc
>