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Date:   Fri, 25 Feb 2022 16:56:21 +0100
From:   Marc Kleine-Budde <mkl@pengutronix.de>
To:     Hangyu Hua <hbh25y@gmail.com>
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
Subject: Re: [PATCH] can: usb: fix a possible memory leak in
 esd_usb2_start_xmit
Message-ID: <20220225155621.7zmfukra63qcxjo5@pengutronix.de>
References: <20220225060019.21220-1-hbh25y@gmail.com>
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On 25.02.2022 14:00:19, Hangyu Hua wrote:
> As in case of ems_usb_start_xmit, dev_kfree_skb needs to be called when
> usb_submit_urb fails to avoid possible refcount leaks.

Thanks for your patch. Have you tested that there is actually a mem
leak? Please have a look at the can_free_echo_skb() function that is
called a few lines earlier.

> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
> ---
>  drivers/net/can/usb/esd_usb2.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>=20
> diff --git a/drivers/net/can/usb/esd_usb2.c b/drivers/net/can/usb/esd_usb=
2.c
> index 286daaaea0b8..7b5e6c250d00 100644
> --- a/drivers/net/can/usb/esd_usb2.c
> +++ b/drivers/net/can/usb/esd_usb2.c
> @@ -810,7 +810,7 @@ static netdev_tx_t esd_usb2_start_xmit(struct sk_buff=
 *skb,
>  		usb_unanchor_urb(urb);
> =20
>  		stats->tx_dropped++;
> -
> +		dev_kfree_skb(skb);
>  		if (err =3D=3D -ENODEV)
>  			netif_device_detach(netdev);
>  		else

regards,
Marc

--=20
Pengutronix e.K.                 | Marc Kleine-Budde           |
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Vertretung West/Dortmund         | Phone: +49-231-2826-924     |
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