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Message-ID: <67219c6e-7eef-ee5c-693c-215a4d4c1b3e@eknoes.de>
Date:   Fri, 22 Jul 2022 13:59:40 +0200
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Subject: Re: [PATCH] Bluetooth: virtio_bt: Use skb_put to set length
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To:     Marcel Holtmann <marcel@holtmann.org>,
        Johan Hedberg <johan.hedberg@gmail.com>,
        Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Cc:     linux-bluetooth@vger.kernel.org
References: <20220614145253.132230-1-soenke.huster@eknoes.de>
From:   =?UTF-8?Q?S=c3=b6nke_Huster?= <soenke.huster@eknoes.de>
In-Reply-To: <20220614145253.132230-1-soenke.huster@eknoes.de>
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Precedence: bulk

On 14.06.22 16:52, Soenke Huster wrote:
> By using skb_put we ensure that skb->tail is set
> correctly. Currently, skb->tail is always zero, which
> leads to errors, such as the following page fault in
> rfcomm_recv_frame:
> 
>     BUG: unable to handle page fault for address: ffffed1021de29ff
>     #PF: supervisor read access in kernel mode
>     #PF: error_code(0x0000) - not-present page
>     RIP: 0010:rfcomm_run+0x831/0x4040 (net/bluetooth/rfcomm/core.c:1751)
> 
> Signed-off-by: Soenke Huster <soenke.huster@eknoes.de>
> ---
>  drivers/bluetooth/virtio_bt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/bluetooth/virtio_bt.c b/drivers/bluetooth/virtio_bt.c
> index 67c21263f9e0..fd281d439505 100644
> --- a/drivers/bluetooth/virtio_bt.c
> +++ b/drivers/bluetooth/virtio_bt.c
> @@ -219,7 +219,7 @@ static void virtbt_rx_work(struct work_struct *work)
>  	if (!skb)
>  		return;
>  
> -	skb->len = len;
> +	skb_put(skb, len);
>  	virtbt_rx_handle(vbt, skb);
>  
>  	if (virtbt_add_inbuf(vbt) < 0)

Are there any issues with it, or is there another reason why it is not merged yet?