Re: safe mallocs (was Re: vulndev-1 and a suggestion about the ensuing discussion)

From: William Robertson (wkrat_private)
Date: Tue May 20 2003 - 00:09:10 PDT

  • Next message: mayhemat_private: "ELF ET_REL injection into ET_EXEC"

    On 16 May 2003, xenophi1e [oliver.laveryat_private] wrote:
    | There are probably better schemes, but this has the nice property of
    | being something you could retrofit without breaking the world. Well, at
    | least something you could kinda retrofit if it weren't for some nasty
    | implementation details. Are there any products like StackGuard that do
    | something like this?
    | 
    | Cheers,
    | ~x
    
    My apologies for jumping into this thread so late, but I'm still catching
    up on my list mail after being out of town last week.  Anyway, some
    colleagues of mine and I will be presenting a paper on this topic at LISA
    2003.  We have an experimental patch for glibc which successfully detects
    and prevents heap-based buffer overrun exploits using a random XORed canary
    technique.  It is fully backwards-compatible with existing software,
    requiring only a recompilation of glibc for system-wide coverage, and can
    also be used selectively using LD_PRELOAD tricks.  We are also working on
    ports to the various *BSD allocators.
    
    We're currently running tests and gathering performance data for our paper,
    but if anyone is interested in helping to beta test and/or audit, feel free
    to email me offline.  We are very interested in ironing out any kinks;
    based on our testing to date, we believe this is a viable approach to
    mitigating heap overrun exploits.
    
    -- 
    | William Robertson | 0x4218A2A6 | wkrat_private |
    



    This archive was generated by hypermail 2b30 : Tue May 20 2003 - 10:07:23 PDT