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    SubjectRe: [PATCH] Undo some of the pseudo-security madness
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    > No amount of carefulness will prevent vendors stick arbitrarily
    > damaging values of stack and mmap base randomisation, severely reducing
    > the usefullness of MAP_FIXED.

    MAP_FIXED is useful still. The only safe way is to use addresses you got
    from mmap(), eg you overmap something.
    Anything else is madness, with or without randomization. The C library
    for example is free, and does, allocate memory and stacks etc etc.

    Same for many other libraries; in addition libraries change in size all
    the time... MAP_FIXED of an address you don't KNOW is free is a bug.
    Period.
    (using an address previously obtained from mmap() is safest, but you
    could in theory also parse /proc/self/maps, although that is racey,
    since nothing guarantees that the C library didn't spawn a background
    thread that allocates memory)


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