Re: [lwip-devel] Problem with LWIP_ERROR in pbuf_header(..)

[Fredrik Hederstierna]

> >   /* Check minimum length (IP header
+ UDP header) 
> >    * and move payload pointer to UDP header */ 
> >   if (p->tot_len < (IPH_HL(iphdr) * 4 + UDP_HLEN)
|| pbuf_header(p, -
> > (s16_t)(IPH_HL(iphdr) * 4))) { 
> > 
> > 
> > That is if incomming UDP packet is too short, so the call to
> > pbuf_header() will trig LWIP_ERROR? 
> > Isn't it better to just drop illegal-size packets instead of
ASSERT? 
> > What if header and header length is corrupted? 

I'm thinking of applying this attached patch to UDP,
ICMP, IGMP, and TCP.





I've changed to checks size _before_ call to pbuf_header,
and also use "len" instead of "tot_len".

Do you think its valid?

Best regards
Fredrik

lwip_pbuf_len.patch
Description: Binary data