Re: skb_checksum_help

[Patrick McHardy <kaber@xxxxxxxxx>]

Thomas Graf wrote:

> I CC'ed netdev, this seems more serious than I thought.
>
> Background: David noticed the assertion csum + 2 > offset being trigged
> in skb_checksum_help. I sent him a patch converting it into a warning
> printing offset, len, n.raw, tail, csum, features and the whole packet
> as hexdump. He uses the acenic driver which is actually capable of doing
> IP checksumming. (Patch enclosed at the end)
How does the backtrace look ?

> > skb hdr corrupted!
The check looks bogus:

> +               if (skb->h.raw < skb->data || skb->h.raw > skb->data)
> +                       printk(KERN_CRIT "skb hdr corrupted!\n");
> +               goto out;
> +       }
Regards
Patrick