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Message-ID: <0d2f9980-fb1d-4068-7868-effc77892a97@gmail.com>
Date:   Mon, 21 Mar 2022 09:47:30 +0800
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Subject: Re: [PATCH] can: mcba_usb: fix possible double dev_kfree_skb in
 mcba_usb_start_xmit
Content-Language: en-US
To:     yashi@spacecubics.com, wg@grandegger.com, mkl@pengutronix.de,
        davem@davemloft.net, kuba@kernel.org, mailhol.vincent@wanadoo.fr,
        stefan.maetje@esd.eu, paskripkin@gmail.com,
        remigiusz.kollataj@mobica.com
Cc:     linux-can@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20220311080208.45047-1-hbh25y@gmail.com>
From:   Hangyu Hua <hbh25y@gmail.com>
In-Reply-To: <20220311080208.45047-1-hbh25y@gmail.com>
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Gentle ping.

On 2022/3/11 16:02, 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: 51f3baad7de9 ("can: mcba_usb: Add support for Microchip CAN BUS Analyzer")
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
> ---
>   drivers/net/can/usb/mcba_usb.c | 1 -
>   1 file changed, 1 deletion(-)
> 
> diff --git a/drivers/net/can/usb/mcba_usb.c b/drivers/net/can/usb/mcba_usb.c
> index 77bddff86252..7c198eb5bc9c 100644
> --- a/drivers/net/can/usb/mcba_usb.c
> +++ b/drivers/net/can/usb/mcba_usb.c
> @@ -364,7 +364,6 @@ static netdev_tx_t mcba_usb_start_xmit(struct sk_buff *skb,
>   xmit_failed:
>   	can_free_echo_skb(priv->netdev, ctx->ndx, NULL);
>   	mcba_usb_free_ctx(ctx);
> -	dev_kfree_skb(skb);
>   	stats->tx_dropped++;
>   
>   	return NETDEV_TX_OK;