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    SubjectRe: symlinks with permissions
    On Mon 2009-10-26 14:22:16, Trond Myklebust wrote:
    > On Sun, 2009-10-25 at 10:36 +0100, Pavel Machek wrote:
    > > Well, it is unexpected and mild security hole.
    > >
    > > Part of the problem is that even if you have read-only
    > > filedescriptor, you can upgrade it to read-write, even if path is
    > > inaccessible to you.
    > >
    > > So if someone passes you read-only filedescriptor, you can still write
    > > to it.
    >
    > If someone passes you a file descriptor, can't you in any case play
    > games with, openat(fd,"",O_RDWR), in order to achieve the same thing? I
    > must admit I haven't tried it yet, but at a first glance I can't see
    > anything that prevents me from doing this...

    According to my documentation, openat needs directory fd.
    Pavel
    --
    (english) http://www.livejournal.com/~pavelmachek
    (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


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