Re: [PATCH v4 00/10] Function Granular KASLR

Hi -

quoted

We have relocated based on sections, not some subset of function
symbols accessible that way, partly because DWARF line- and DIE- based
probes can map to addresses some way away from function symbols, into
function interiors, or cloned/moved bits of optimized code.  It would
take some work to prove that function-symbol based heuristic
arithmetic would have just as much reach.

Interesting. Do you have an example handy? 

No, I'm afraid I don't have one that I know cannot possibly be
expressed by reference to a function symbol only.  I'd look at
systemtap (4.3) probe point lists like:

% stap -vL 'kernel.statement("*@kernel/*verif*.c:*")'
% stap -vL 'module("amdgpu").statement("*@*execution*.c:*")'

which give an impression of computed PC addresses.

It seems like something like that would reference the enclosing
section, which means we can't just leave them out of the sysfs
list... (but if such things never happen in the function-sections,
then we *can* remove them...)

I'm not sure we can easily prove they can never happen there.

- FChE