From: Danek Duvall <duvall@comfychair.org>
To: Bart Schaefer <schaefer@brasslantern.com>
Cc: Zsh hackers list <zsh-workers@zsh.org>
Subject: Re: [PATCH] Re: Insecure tempfile creation
Date: Wed, 7 Jan 2015 22:48:16 -0800 [thread overview]
Message-ID: <20150108064816.GA17816@lorien.comfychair.org> (raw)
In-Reply-To: <CAH+w=7Y3r3UeFPdHjPsS9arrWWjss2Bco1i0hNsn6fb8sfv7Xw@mail.gmail.com>
On Wed, Jan 07, 2015 at 10:22:20PM -0800, Bart Schaefer wrote:
> On Wed, Jan 7, 2015 at 2:03 PM, Daniel Shahaf <d.s@daniel.shahaf.name> wrote:
> > Coming back to this, it has occurred to me that
> >
> > mv -f =(:) ${TMPPREFIX:-/tmp/zsh}foo$$
> >
> > wouldn't perform an atomic rename (as intended) if /tmp/zshfoo$$ is a
> > directory or symlink-to-directory. So hypothetically an attacker might
> > be able to create a file named `basename =(:)` in a directory of his
> > choice owned by the victim.
>
> Hmm. Yup, we need "ln -Fh" instead of "mv -f". Are the -F and -h
> options of "ln" fairly standard?
Neither exists on Solaris ln. GNU coreutils ln doesn't seem to have -h,
either. And -F just seems like a bad idea, supported or not.
What about mktemp? The above construction is pretty weird, anyway. If an
external command isn't desired, then mktemp seems like a reasonable thing
to make builtin.
Danek
next prev parent reply other threads:[~2015-01-08 6:57 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-12-22 20:36 Daniel Shahaf
2014-12-22 22:01 ` Mikael Magnusson
2014-12-23 2:07 ` Bart Schaefer
2014-12-28 6:30 ` Bart Schaefer
2014-12-28 7:44 ` [PATCH] " Bart Schaefer
2014-12-28 8:41 ` Bart Schaefer
2014-12-29 0:49 ` Daniel Shahaf
2014-12-29 4:01 ` Bart Schaefer
2015-01-07 22:03 ` Daniel Shahaf
2015-01-08 6:22 ` Bart Schaefer
2015-01-08 6:48 ` Danek Duvall [this message]
2015-01-08 8:08 ` Bart Schaefer
2015-01-08 14:10 ` Daniel Shahaf
2015-01-08 14:24 ` Peter Stephenson
2015-01-08 16:35 ` Ray Andrews
2015-01-08 17:40 ` Peter Stephenson
2015-01-09 2:51 ` Mikael Magnusson
2015-01-09 9:02 ` Peter Stephenson
2015-01-09 12:51 ` Peter Stephenson
2015-01-09 13:35 ` Peter Stephenson
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