Iam working with kernel to find the security holes and to fix it .

I find most of the problems upto kernel 2.4 and I have found more security patches to prevent this security holes like LIDS.openwall.etc.,

my questions is whether all the security holes are fixed in kernel 2.6 ?.
I find they have included grsecurity in kernel 2.6.
since Iam doing some research on this kernel level security. I need the
help from u.