commit da521b2c4f046383bc8941604174bc0e8bffb430
author David S. Miller <davem@davemloft.net> Tue Dec 21 12:43:16 2010 -0800
committer David S. Miller <davem@davemloft.net> Tue Dec 21 12:43:16 2010 -0800
tree e3678d5af507054c86f1d913ad1599f4afee1c7d
parent aa3e219997e4b949be4199660936099ded0b401f

net: Fix range checks in tcf_valid_offset().

This function has three bugs:

1) The offset should be valid most of the time, this is just
   a sanity check, therefore we should use "likely" not "unlikely"

2) This is the only place where we can check for arithmetic overflow
   of the pointer plus the length.

3) The existing range checks are off by one, the valid range is
   skb->head to skb_tail_pointer(), inclusive.

Based almost entirely upon a patch by Ralph Loader.

Reported-by: Ralph Loader <suckfish@ihug.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>