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From: Willy Tarreau <w@1wt.eu>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>,
	Sarah Sharp <sarah.a.sharp@linux.intel.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Marcus Meissner <meissner@suse.de>,
	linux-kernel@vger.kernel.org, tj@kernel.org,
	akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk
Subject: Re: [PATCH] kernel: make /proc/kallsyms mode 400 to reduce ease of attacking
Date: Mon, 29 Nov 2010 22:49:33 +0100	[thread overview]
Message-ID: <20101129214933.GD8442@1wt.eu> (raw)
In-Reply-To: <4CF3F996.4090703@zytor.com>

On Mon, Nov 29, 2010 at 11:05:58AM -0800, H. Peter Anvin wrote:
> Can we please not use CAP_SYS_ADMIN for this?  Relying on CAP_SYS_ADMIN
> is worse than anything else -- it is a fixed policy hardcoded in the
> kernel, with no ability for the system owner to delegate the policy
> outward, e.g. by adding group read permission and/or chgrp the file.
> 
> Delegating CAP_SYS_ADMIN, of course, otherwise known as "everything", is
> worse than anything...

Agreed, that's why I still think that hiding lots of valuable information to
non-root users will get more users added to unmanaged sudoers files, which
will result in much more holes in the systems than we currently have.

Willy


  parent reply	other threads:[~2010-11-29 21:50 UTC|newest]

Thread overview: 54+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-11-16 10:46 [PATCH] kernel: make /proc/kallsyms mode 400 to reduce ease of attacking Marcus Meissner
2010-11-17  5:07 ` Kyle McMartin
2010-11-18  7:48   ` Ingo Molnar
2010-11-20  3:18     ` Kees Cook
2010-11-26  7:51       ` Ingo Molnar
2010-11-17  5:40 ` Kyle Moffett
2010-11-17  5:41   ` Kyle Moffett
2010-11-17  5:58   ` Linus Torvalds
2010-11-17  6:19     ` Willy Tarreau
2010-11-18  7:31   ` Ingo Molnar
2010-11-23 17:24     ` Pavel Machek
2010-11-26  7:38       ` Ingo Molnar
2010-11-29 19:03         ` H. Peter Anvin
2010-11-20 11:32   ` Avi Kivity
2010-11-19 19:19 ` Sarah Sharp
2010-11-19 19:54   ` Linus Torvalds
2010-11-19 19:58     ` david
2010-11-19 20:04       ` Linus Torvalds
2010-11-19 20:16         ` Willy Tarreau
2010-11-19 20:55           ` david
2010-11-26  7:48     ` Ingo Molnar
2010-11-29 16:33       ` Sarah Sharp
2010-11-29 18:04         ` Ingo Molnar
2010-11-29 19:05           ` H. Peter Anvin
2010-11-29 19:21             ` Eric Paris
2010-11-29 19:38               ` H. Peter Anvin
2010-11-29 21:49             ` Willy Tarreau [this message]
2010-11-29 23:31         ` Alan Cox
2010-11-30 11:58           ` Ingo Molnar
2010-11-20 11:05 ` Richard W.M. Jones
  -- strict thread matches above, loose matches on Subject: below --
2010-11-19 21:12 Andy Walls
2010-11-19 23:22 ` Linus Torvalds
2010-11-20  2:40   ` Kees Cook
2010-11-20 19:47     ` Henrique de Moraes Holschuh
2010-11-29 22:58       ` Kevin Easton
2010-11-04 10:09 Marcus Meissner
2010-11-04 10:11 ` Tejun Heo
2010-11-04 11:46 ` Ingo Molnar
2010-11-04 12:29   ` Marcus Meissner
2010-11-04 13:58     ` Ingo Molnar
2010-11-04 14:11       ` Ingo Molnar
2010-11-04 14:33         ` Marcus Meissner
2010-11-04 14:38           ` Tejun Heo
2010-11-04 14:43             ` H. Peter Anvin
2010-11-04 14:48               ` Tejun Heo
2010-11-04 19:08           ` Ingo Molnar
2010-11-07 18:02           ` Andi Kleen
2010-11-07 18:32             ` H. Peter Anvin
2010-11-10  8:53               ` Ingo Molnar
2010-11-11  2:51                 ` H. Peter Anvin
2010-11-11  7:05                   ` Ingo Molnar
2010-11-05  2:38     ` Frank Rowand
2010-11-10 20:58       ` Jesper Juhl
2010-11-05  0:20 ` Jesper Juhl

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