[gentoo-dev] Re: Improve the security of the default profile

[Martin Vaeth]

Ryan Hill <dirtyepic@g.o> wrote:
> Martin Vaeth <vaeth@××××××××××××××××××××××××.de> wrote:
>> >
>> > * -fstack-protector{-all}
>> > No thank you.  -fstack-protector has very limited coverage
>>
>> I'd say it covers most cases where bugs can be made, [...]
>
> The numbers I've seen show a maximum of 5% coverage for code that has a
> large number of functions containing char arrays on the stack.

If you have no local array on the stack, it is rather hard to write
accidentally(!) code in the function which corrupts the stack.
(It still is possible e.g. through bad casting, but it is rather
unlikely that this happens by accident).
So coverage of these functions covers most cases of accidental bugs.
Of course, as Ciaranm already mentioned, there is no compiler flag
which transforms unsafe code into safe one, but if even just one or
two security bugs can be avoid this way, it was worth to add
this flag IMHO.

> Most code doesn't fall into that category.

Isn't this good news? It means most code will not get *any*
penalty with -fstack-protector.