Re: [PATCH] fix infoleak in ioctl_cfg80211

[Greg KH]

On Tue, May 03, 2016 at 06:11:46PM -0400, Kangjie Lu wrote:
> "mac" is an array allocated in stack without being initialized,
> and will be sent out via "nla_put". The dump_station() is supposed
> to initialize the mac address; otherwise, sensitive data in kernel
> stack will be leaked. To fix this, either initialize it (e.g.,
> memset) or completely remove this dump_station().
> 
> Signed-off-by: Kangjie Lu <kjlu@xxxxxxxxxx>
> ---
>  drivers/staging/rtl8723au/os_dep/ioctl_cfg80211.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/staging/rtl8723au/os_dep/ioctl_cfg80211.c b/drivers/staging/rtl8723au/os_dep/ioctl_cfg80211.c
> index 12d1844..44a1582 100644
> --- a/drivers/staging/rtl8723au/os_dep/ioctl_cfg80211.c
> +++ b/drivers/staging/rtl8723au/os_dep/ioctl_cfg80211.c
> @@ -2926,6 +2926,7 @@ static int cfg80211_rtw_dump_station(struct wiphy *wiphy,
>  
>  	/* TODO: dump scanned queue */
>  
> +	memset(mac, 0, ETH_ALEN);
>  	return -ENOENT;
>  }

This isn't needed, as it returns -ENOENT and so mac never gets used.

thanks,

greg k-h