Subject: Re: [PATCH v2] net: usb: lan78xx: Limit packet length to skb->len

From: Greg KH <[email-masked]>
Date: Thu, 23 Mar 2023 17:29:44 +0100

On Fri, Mar 17, 2023 at 06:36:06PM +0100, Szymon Heidrich wrote:
> Packet length retrieved from descriptor may be larger than
> the actual socket buffer length. In such case the cloned
> skb passed up the network stack will leak kernel memory contents.
> 
> Additionally prevent integer underflow when size is less than
> ETH_FCS_LEN.
> 
> Fixes: 55d7de9de6c3 ("Microchip's LAN7800 family USB 2/3 to 10/100/1000 Ethernet device driver")
> Signed-off-by: Szymon Heidrich <[email-masked]>
> Reported-by: kernel test robot <[email-masked]>

the test robot did not report the fact that the packet length needed to
be limited :(