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Date:   Thu, 29 Mar 2018 14:50:36 -0600
From:   Jonathan Corbet <corbet@lwn.net>
To:     Igor Stoppa <igor.stoppa@gmail.com>
Cc:     Igor Stoppa <igor.stoppa@huawei.com>, willy@infradead.org,
        keescook@chromium.org, mhocko@kernel.org, david@fromorbit.com,
        rppt@linux.vnet.ibm.com, labbott@redhat.com,
        linux-security-module@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com
Subject: Re: [RFC PATCH v21 0/6] mm: security: ro protection for dynamic
 data
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        <20180327105509.62ec0d4d@lwn.net>
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On Fri, 30 Mar 2018 00:25:22 +0400
Igor Stoppa <igor.stoppa@gmail.com> wrote:

> On 27/03/18 20:55, Jonathan Corbet wrote:
> > On Tue, 27 Mar 2018 18:37:36 +0300
> > Igor Stoppa <igor.stoppa@huawei.com> wrote:
> >   
> >> This patch-set introduces the possibility of protecting memory that has
> >> been allocated dynamically.  
> > 
> > One thing that jumps out at me as I look at the patch set is: you do not
> > include any users of this functionality.  Where do you expect this
> > allocator to be used?  Actually seeing the API in action would be a useful
> > addition, I think.  
> 
> Yes, this is very true.
> Initially I had in mind to use LSM hooks as easy example, but sadly they 
> seem to be in an almost constant flux.
> 
> My real use case is to secure both those and the SELinux policy DB.
> I have said this few times, but it didn't seem to be worth mentioning in 
> the cover letter.

In general, it is quite hard to merge a new API without users to go along
with it.  Among other things, that's how reviewers can see how well the
API works in real-world use.  I am certainly not the one who will make the
decision on whether this goes in, but I suspect that whoever *does* make
that decision would prefer to see some users.

Thanks,

jon