From: Chris Wright <chris@wirex.com>
To: xystrus <xystrus@haxm.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: link() security
Date: Thu, 11 Apr 2002 18:15:24 -0700 [thread overview]
Message-ID: <20020411181524.A1463@figure1.int.wirex.com> (raw)
In-Reply-To: <20020411192122.F5777@pizzashack.org>
* xystrus (xystrus@haxm.com) wrote:
>
> Is there a good reason why a user can successfully link() a file to
> which they do not have any access?
Other than the fact that it's standard behaviour? ;-) Well, the SUS
actually makes an allowance for this:
"The implementation may require that the calling process has
permission to access the existing file."
If you are interested, the Openwall patch does just this (among other things)
http://openwall.com. Work based on Solar Designer's Openwall patch has
been brought forward to more recent 2.4 and 2.5 kernels. Both the
following projects implement the Openwall secure link feature:
http://grsecurity.net
http://lsm.immunix.org
This can break some applications that make assumptions wrt. link(2)
(Courier MTA for example).
cheers,
-chris
next prev parent reply other threads:[~2002-04-12 1:15 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-04-11 23:21 link() security xystrus
2002-04-12 1:15 ` Chris Wright [this message]
2002-04-13 16:59 ` Alan Cox
2002-04-13 17:02 ` xystrus
2002-04-14 1:49 ` Chris Wright
2002-04-15 14:44 ` Patrick J. LoPresti
2002-04-15 19:25 ` H. Peter Anvin
2002-04-15 22:48 ` Alan Cox
2002-04-15 23:05 ` H. Peter Anvin
2002-04-15 23:28 ` Alan Cox
2002-04-15 23:14 ` H. Peter Anvin
2002-04-16 0:01 ` Kurt Wall
2002-04-15 21:41 ` xystrus
2002-05-06 5:00 ` Albert D. Cahalan
-- strict thread matches above, loose matches on Subject: below --
2002-04-13 17:48 Hank Leininger
2002-04-15 19:36 Chris Adams
2002-04-15 19:55 ` H. Peter Anvin
2002-04-15 20:36 ` Patrick J. LoPresti
2002-04-16 1:37 ` H. Peter Anvin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20020411181524.A1463@figure1.int.wirex.com \
--to=chris@wirex.com \
--cc=linux-kernel@vger.kernel.org \
--cc=xystrus@haxm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox