TCPv4 checksum errors

[David S. Miller]

   From: Alan Cox <alan at cymru.net>
   Date: Wed, 23 Dec 1998 21:58:04 +0000 (GMT)

   The classic bad packet error is a frame that ends up with

   checksum =FFFF end around carry left =1

I challenge you to generate a packet which will create this condition,
it is impossible as far as I have tried....

However, I'm very very interested in being proved wrong.  Because if I
am, then every single checksum implementation in the kernel would need
to be fixed and we should therefore settle this asap.

Instead of tiring one's brain like I did, to find if the case even
exists, better would probably be to put a piece of debugging code
which checked for this condition and printed out a nice message and
dumped the packet contents when triggered.

Later,
David S. Miller
davem at dm.cobaltmicro.com

[[ This message was sent via the linuxppc-dev mailing list. Replies are ]]
[[ not forced back to the list, so be sure to  Cc linuxppc-dev  if your ]]
[[ reply is of general interest. To unsubscribe from linuxppc-dev, send ]]
[[ the message 'unsubscribe' to linuxppc-dev-request at lists.linuxppc.org ]]