linux-kernel - Re: [PATCH 1/3] IMA: move read/write counters into struct inode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <19646.63514.852665.500420@quad.stoffel.home>
Date:	Wed, 20 Oct 2010 10:09:30 -0400
From:	"John Stoffel" <john@...ffel.org>
To:	Al Viro <viro@...IV.linux.org.uk>
Cc:	John Stoffel <john@...ffel.org>,
	Mimi Zohar <zohar@...ux.vnet.ibm.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Eric Paris <eparis@...hat.com>, linux-kernel@...r.kernel.org,
	linux-security-module@...r.kernel.org,
	linux-fsdevel@...r.kernel.org, hch@...radead.org,
	Mimi Zohar <zohar@...ibm.com>, warthog9@...nel.org,
	david@...morbit.com, jmorris@...ei.org, kyle@...artin.ca,
	hpa@...or.com, akpm@...ux-foundation.org, mingo@...e.hu
Subject: Re: [PATCH 1/3] IMA: move read/write counters into struct inode

>>>>> "Al" == Al Viro <viro@...IV.linux.org.uk> writes:

Al> On Wed, Oct 20, 2010 at 09:10:27AM -0400, John Stoffel wrote:
>> Does this mean I can't replace /bin/sh on a running system using IMA
>> at all, even if just one process has it opened and is running?  So how
>> the hell am I supposed to do live upgrades on a system?  

Al> rename(2).  Prohibition against write(2) to binary being executed is
Al> *old*.  Try to do the following:
Al> cp /bin/sh /tmp
Al> /tmp/sh &
Al> cat /bin/ls >/tmp/sh
Al> and you'll get
Al> sh: /tmp/sh: Text file busy

Al> That has nothing to do with IMA...

Duh, makes sense.  Thanks for educating me.  I still IMA is a waste of
system resources...

John
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/