Re: Proposal: restrict link(2)

Matthias Urlichs (smurf@noris.de)
12 Dec 1996 11:40:55 +0100

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In linux.dev.kernel, article <m0vXnoO-0001bNC@ceres.tat.physik.uni-tuebingen.de>,
koenig@tat.physik.uni-tuebingen.de (Harald Koenig) writes:
>
> why is Joe Random Cracker allowed to make a hard link to /etc/passwd at all
> (or to any other file not owed by him) ?
>
Because that's the Unix semantics. If you can write to a directory and you
can execute the directory a file resides in, then you can make a link to
that file.

Face it, people, setuid-root programs are _difficult_ to get right. Unless
we get an ACL implementation with appropriately-fine-grained rights it will
IMHO never be possible to find all the holes.

-- Talent is what you possess; genius is what possesses you.

-- 
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Next message: Samuel S Chessman: "Re: Mega Patch #8, or "Why stop now while we haven't broken it all""
Previous message: Christian Balzer: "VFS: grow_buffers:, MD, RAID-O problem."
Maybe in reply to: Thomas Koenig: "Proposal: restrict link(2)"
Next in thread: Adam D. Bradley: "Re: Proposal: restrict link(2)"