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    SubjectRe: [PATCH] Check files' signatures before doing suid/sgid [2/4]

    Hi,

    > >If a process uses read() it needs some executable and writable memory. We do
    > >check for this in mprotect(). There is a problem with the i386-architecture,
    > >because it allows execution of any readable page (except with newer
    > >processors). But beyond that ugliness of i386, it should not be possible to
    > >execute anything without us noticing it (hopefully).
    >
    > r and x together is not a problem IMHO.

    It is, if you would want to have rw but can only get rwx.
    regards,
    Johannes

    --
    Johannes Schlumberger Department of Computer Science IV
    Martensstrasse 1 D-91058 Erlangen Germany University of Erlangen-Nuremberg
    http://wwwcip.informatik.uni-erlangen.de/~spjsschl
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