The 4th argument for in[46]_cksum() should be length of L4 header +
L4 payload. The previous revisions are wrong
- for IPv4 when hdrlen != 0
- for IPv6 always
These functions are used only in net/if_loop.c and
arch/powerpc/booke/dev/pq3etsec.c under some special circumferences.
This should be why the bugs have not been found until today.
OK maxv