[lwip-devel] [bug #56708] ip6_debug_print is called in ip6_input at the wrong place

[Gunar Schorcht]

Follow-up Comment #1, bug #56708 (project lwip):


[comment #0 original submission:]
> The call of function `ip6_debug_print` to print the header of a received
IPv6 packet is at the wrong place in function `ip6_input`.
> 
> In current source, function `ip6_debug_print` is called in [line 1044 in
ip6.c](http://git.savannah.nongnu.org/cgit/lwip.git/tree/src/core/ipv6/ip6.c#n1044).
However, this is after the header has been already removed with
> 
> <code>
> `pbuf_remove_header(p, IP6_HLEN)`;
> 
> </code>
> 
> in [line 704 in
ipv6](http://git.savannah.nongnu.org/cgit/lwip.git/tree/src/core/ipv6/ip6.c#n1044).
Therefore, the call results into an output that makes no sense, for example:
> 
> <code>
> IPv6 header:
> +-------------------------------+
> |  3 |    3  |       638977     | (ver, class, flow)
> +-------------------------------+
> |     39724     |  127  |   45  | (plen, nexth, hopl)
> +-------------------------------+
> |     0 |  196e |  6012 |  7080 | (src)
> |  f128 |     0 |   204 |   5a0 |
> +-------------------------------+
> |   7d0 |   101 |  6ad3 |  9b1a | (dest)
> |   7d1 |  5425 |  7c22 |     0 |
> +-------------------------------+
> ip6_input: p->len 24 p->tot_len 24
> </code>
> 
> In this example, the payload (TCP Header) is interpreted as IPv6 Header.
Also the given length of `*p` is less than the minimum size of 40 byte of an
IPv6 header.
> 
> From my point of view, the debug output should be placed at [line 697 in
ip6.c](http://git.savannah.nongnu.org/cgit/lwip.git/tree/src/core/ipv6/ip6.c#n697).

    _______________________________________________________

Reply to this item at:

  <https://savannah.nongnu.org/bugs/?56708>

_______________________________________________
  Message sent via Savannah
  https://savannah.nongnu.org/