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Subject: Re: ima: use of radix tree cache indexing == massive waste of
 memory?
From: Peter Zijlstra <peterz@infradead.org>
To: "Ted Ts'o" <tytso@mit.edu>
Cc: Eric Paris <eparis@redhat.com>, Eric Paris <eparis@parisplace.org>,
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Date: Mon, 18 Oct 2010 17:02:02 +0200
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On Mon, 2010-10-18 at 10:59 -0400, Ted Ts'o wrote:
> On Mon, Oct 18, 2010 at 01:57:28PM +0200, Peter Zijlstra wrote:
> > Well, you could use the actual freezer to freeze luserspace and then
> > simply iterate all open files, I mean, those few sods who actually want
> > this enabled can either pass a boot option to enable from boot or suffer
> > the overhead on enable, right?
> 
> I'm a little confused why anyone would want to turn on IMA at any time
> other than right away at boot?  If you haven't been doing integrity
> management checking from the very beginning of the boot process, what
> does turning on IMA after the system has booted buy you in the way of
> security protections?
> 
> In other words, turning on IMA via a boot option seems to be the only
> thing that makes any sense at all.

Fine with me.. I simply understood there was a requirement for post-boot
enablement and tried to come up with a solution for that.