# Re: \[patch -next\] wan/fsl\_ucc\_hdlc: info leak in uhdlc\_ioctl()

- From: walter harms \<hidden\>
- Date: 2016-07-14 10:59:54 
- List: netdev
- Page: https://ratatoskr.run/netdev/2016/07/9491271
- Thread: https://ratatoskr.run/netdev/2016/07/9491269/t.md

```text


Am 14.07.2016 12:34, schrieb Dan Carpenter:
> There is a 2 byte struct whole after line.loopback so we need to clear
> that out to avoid disclosing stack information.
> 
> Fixes: c19b6d246a35 ('drivers/net: support hdlc function for QE-UCC')
> Signed-off-by: Dan Carpenter <redacted>
> 
> diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
> index 19174ac..7608561 100644
> --- a/drivers/net/wan/fsl_ucc_hdlc.c
> +++ b/drivers/net/wan/fsl_ucc_hdlc.c
> @@ -635,6 +635,7 @@ static int uhdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
>  			ifr->ifr_settings.size = size; /* data size wanted */
>  			return -ENOBUFS;
>  		}
> +		memset(&line, 0, sizeof(line));
>  		line.clock_type = priv->clocking;
>  		line.clock_rate = 0;
>  		line.loopback = 0;


In this case
  		line.clock_rate = 0;
 		line.loopback = 0;

are not need any more and can be removed
except like them to have for documentation or so.

re,
 wh
```