Re: [PATCH net] nfc: fix potential illegal memory access

[David Miller]

From: Yang Wei <albin_yang@xxxxxxx>
Date: Sun,  7 Jul 2019 21:37:40 +0800

> The frags_q is used before __skb_queue_head_init when conn_info is
> NULL. It may result in illegal memory access.
> 
> Signed-off-by: Yang Wei <albin_yang@xxxxxxx>
> ---
>  net/nfc/nci/data.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/net/nfc/nci/data.c b/net/nfc/nci/data.c
> index 0a0c265..b5f16cb 100644
> --- a/net/nfc/nci/data.c
> +++ b/net/nfc/nci/data.c
> @@ -104,14 +104,14 @@ static int nci_queue_tx_data_frags(struct nci_dev *ndev,
>  
>  	pr_debug("conn_id 0x%x, total_len %d\n", conn_id, total_len);
>  
> +	__skb_queue_head_init(&frags_q);
> +
>  	conn_info = nci_get_conn_info_by_conn_id(ndev, conn_id);
>  	if (!conn_info) {
>  		rc = -EPROTO;
>  		goto free_exit;
>  	}
>  
> -	__skb_queue_head_init(&frags_q);
> -

Just change the goto into "goto exit;", much simpler one-line fix.