ipv4 /proc/net/route bug in 2.4 and 2.5 kernels

[Bruce Cran]

I've discovered a bug in the 2.4 and 2.5 kernels relating to the
information in /proc.   The values reported in /proc/net/route are wrong -
the main error is the MTU field which should be MSS, and should be the
MTU-40.  The route command has the header fixed, but still gets the value
from /proc, and so reports the wrong value of
40.

I'm currently using 2.5.43, and have tracked it down to line 1031 in
net/ipv4/fib_semantics.c in function fib_node_seq_show.  It appears that
fi->fib_advmss is 0, because when I change the '+40' to '+45' that is the
value which appears in the MTU field in /proc/net/route, and in the MSS
field when running '/sbin/route -e'.

Also, on line 191 of net/ipv4/ip_proc.c (in function fib_seq_show), I
think the 'MTU' should be 'MSS' according to the comments in route.c, and
to make the output of the route command and the proc entry consistent.

--
Bruce Cran