Re: Non-executable stack

From: db (db_at_traceroute.dk)
Date: 10/29/05

  • Next message: Colin Percival: "Re: Is the server portion of freebsd-update open source?"
    To: Jimmy Scott <jimmy@inet-solutions.be>, freebsd-security@freebsd.org
    Date: Sat, 29 Oct 2005 14:12:57 +0000
    
    

    On Saturday 29 October 2005 13:15, you wrote:
    > The thing you are refering to is W^X using the NXE register of the amd64
    > if I'm not mistaken, marking memory pages as writable or executable,
    > but not both. (The thing also works on i386 using an ugly hack).

    Yeah. Memory on ia32 can be writable and readable. When it is readable it is
    also executable. On other arch's like AMD64 and IA64, I believe memory can be
    readable, writable and executable. Therefore I would like to remove the
    executable bit on the stack and heap for the systems supporting it.

    br
    db
    _______________________________________________
    freebsd-security@freebsd.org mailing list
    http://lists.freebsd.org/mailman/listinfo/freebsd-security
    To unsubscribe, send any mail to "freebsd-security-unsubscribe@freebsd.org"


  • Next message: Colin Percival: "Re: Is the server portion of freebsd-update open source?"

    Relevant Pages

    • Re: Nocona [Intel 64-bit cpu timing]
      ... memory at 4.5GiB/sec. ... As in the case of the Nocona vs. AMD64. ... my Prescott when on a Pentium M. ... The Prescott tops out at probably around ...
      (sci.crypt)
    • Re: vm.kmem_size settings doesnt affect loader?
      ... If your machine has some small amount of memory, ... then you probably shouldn't be using ZFS. ... The i386 vs. amd64 argument is bogus, ... kernel code and absolutely no experience with kernel memory management. ...
      (freebsd-stable)
    • Re: Nocona [Intel 64-bit cpu timing]
      ... >> to main memory is rare. ... > That'd be an interesting fact except my AMD64 is a dual-core. ... My comment was that dual-core RSA on the ... nocona is STILL SLOWER than a single-core AMD64 running RSA. ...
      (sci.crypt)
    • Re: vm.kmem_size settings doesnt affect loader?
      ... If your machine has some small amount of memory, ... I know that i386 is highly unrecommended for ZFS, but it's just a home box for testing and learning purposes - I just want to know what I'm doing and what should I expect when I decide to put ZFS on server machines:) Currently, from posts on freebsd-fs, I conclude that even with a gigs of kmem and using AMD64, we still can experience panic from kmem_malloc. ... Of course I've followed tuning guide carefully. ...
      (freebsd-stable)
    • Re: swap
      ... I'm wondering how memory gets packed when ... I have both on this AMD64 system, but I find myself most of the time ... packages being compiled for a 64 bit system on a 64 bit system will work ... As for swap space, even in the AMD64 version of Etch that I have, it ...
      (Debian-User)