Re: Buffer overflow prevention

[Jedi/Sector One <j () pureftpd org>]

On Thu, Aug 14, 2003 at 10:17:29PM +0300, Timo Sirainen wrote:
> AFAIK all those combined do bring real security against generic exploits.

  "Real security" is not the word.
  
  PaX / Propolice / W^X / non-exec stacks don't solve bugs. What they do is
to _abort_ execution of a process when it behaves abnormally.

  So instead of giving attackers the opportunity to run arbitrary code, you
only give them the ability to cause a denial of service.

  This kind of protection should be coupled with tools that automatically
restart daemons when they crash (ex: daemontools and monit) to actually keep
the service running when under attack. Still, all of this is a couple of
unreliable band-aids.

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