[CFT/HEADSUP] Ports now have Stack Protector support

[Konstantin Tokarev]

22.09.2013, 19:48, "Eitan Adler" <lists at eitanadler.com>:
> On Sun, Sep 22, 2013 at 10:01 AM, Konstantin Tokarev <annulen at yandex.ru> wrote:
>
>>  21.09.2013, 18:26, "Nathan Whitehorn" <nwhitehorn at freebsd.org>:
>>>  On 09/21/13 09:09, Bryan Drewery wrote:
>>>>   On 9/21/2013 9:00 AM, Nathan Whitehorn wrote:
>>>>>   On 09/21/13 05:47, Bryan Drewery wrote:
>>>>>>   Ports now support enabling Stack Protector [1] support on FreeBSD 10
>>>>>>   i386 and amd64, and older releases on amd64 only currently.
>>>>>   Why only those architectures?
>>>>>   -Nathan
>>>>   I was only able to test on amd64 and i386. And that took 37 exp-runs
>>>>   over a month.
>>>>
>>>>   See commit and CHANGES for more discussion on why not i386 on <10:
>>>>
>>>>   http://svnweb.freebsd.org/ports?view=revision&revision=327697
>>>  OK. If I set this on powerpc anyway, will it turn on? I'm happy to
>>>  (slowly) test it there.
>>  AFAIU, it's pointless to use stack protector on ppc because stack smashing
>>  attacks are just impossible here.
>
> Could you explain why?

Oops, I was wrong. It's impossible to overwrite return address directly by smashing stack (because it's kept in register), but other techniques exist.

-- 
Regards,
Konstantin