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From: Al Viro <viro@ftp.linux.org.uk>
To: Brent Casavant <bcasavan@sgi.com>
Cc: Andreas Schwab <schwab@suse.de>, linux-kernel@vger.kernel.org
Subject: Re: O_NOLINK for open()
Date: Wed, 12 Sep 2007 23:49:55 +0100	[thread overview]
Message-ID: <20070912224955.GC8181@ftp.linux.org.uk> (raw)
In-Reply-To: <20070912172519.N5573@pkunk.americas.sgi.com>

On Wed, Sep 12, 2007 at 05:44:30PM -0500, Brent Casavant wrote:

> P.S. By the way, there doesn't seem to be a way to remove /proc/#/mem
>      files.  That might be an additional nicety -- programs worried about
>      being snooped could unlink their own entry.  /dev/mem and /dev/kmem
>      can simply be removed by the sysadmin of such a system.  If all of
>      that were done you'd have to resort to attacking crash dumps, core
>      dumps, or via something like kdb to extract "hidden" data.

Give me a break.  And learn about ptrace(2).  This "unlinking" bullshit
buys you zero additional security, both for /proc/*/mem and for /dev/mem
(see mknod(2)).

  reply	other threads:[~2007-09-12 22:50 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-09-12 20:37 O_NOLINK for open() Brent Casavant
2007-09-12 21:07 ` H. Peter Anvin
2007-09-12 21:39   ` Brent Casavant
2007-09-12 21:46     ` H. Peter Anvin
2007-09-12 21:42 ` Andreas Schwab
2007-09-12 22:44   ` Brent Casavant
2007-09-12 22:49     ` Al Viro [this message]
2007-09-12 23:27       ` Brent Casavant
2007-09-12 23:48         ` Brent Casavant
2007-09-14 16:37         ` Goswin von Brederlow
2007-09-13 10:08 ` Gabor Gombas
2007-09-13 16:05   ` Brent Casavant
     [not found] <92Haf-7z7-5@gated-at.bofh.it>
2007-09-12 22:33 ` Bodo Eggert
2007-09-13  9:13   ` Jan Kara
2007-09-14  9:07     ` Bodo Eggert
     [not found] ` <92TO5-246-1@gated-at.bofh.it>
     [not found]   ` <92Zqu-2ur-1@gated-at.bofh.it>
2007-09-14 10:30     ` Bodo Eggert
2007-09-14 10:50       ` Andreas Schwab
2007-09-14 17:26         ` Bodo Eggert

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