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    SubjectRe: Patch 4/6 randomize the stack pointer
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    Arjan van de Ven wrote:
    >>I feel the need to point something out here.
    >>
    >>[TEXT][BRK][MMAP---------------][STACK]
    >>
    >>Here's a normal layout.
    >>
    >>[TEXT][BRK][MMAP-------][STACK][MMAP--]
    >>
    >>Is this one any worse?
    >
    >
    > yes.
    >
    > oracle, db2 and similar like to mmap 2Gb or more *in one chunk*.
    > moving the stack in the middle means the biggest chunk they can mmap
    > shrinks.
    >

    Special case?

    I never said these weren't out there. But the point is, who runs
    oracle? Your internal production server, maybe even a cluster, run it
    now. Your desktops don't. Your web server exposed to the net
    shouldn't. Both these are exactly where you *really* want this stuff:
    desktops get exposed to the WWW (and IRC and AIM and God knows what
    else), and web servers get exposed to the HTTP protocol (or ftp or
    whatever).

    Interesting, it's theoretically far less likely that an exploit occurs
    on your server than on your desktop; and the special cases such as your
    Oracle example aren't likely to be sharing a machine with your
    promiscuous touching of everyone else on the Internet with a web browser
    and IRC client, correct?

    Can I get this put into perspective? How much more important is "Good"
    randomization versus "not breaking Oracle," which becomes "No
    randomization" (for Oracle anyway, not for everything else on a
    well-designed system)? How much of an effect does "good" randomization
    have on your web server and desktop machines versus on your internal,
    isolated RDBMS server/cluster?

    More pertainantly (believe it or not), do you even care to ponder these
    questions, or is your next response going to be a stock response?

    >
    >

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