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Subject: Re: [kernel-hardening] [PATCH 4/6] Protectable Memory
To:     Boris Lukashev <blukashev@sempervictus.com>
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From:   Igor Stoppa <igor.stoppa@huawei.com>
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Date:   Sun, 4 Feb 2018 17:05:25 +0200
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On 04/02/18 00:29, Boris Lukashev wrote:
> On Sat, Feb 3, 2018 at 3:32 PM, Igor Stoppa <igor.stoppa@huawei.com> wrote:

[...]

>> What you are suggesting, if I have understood it correctly, is that,
>> when the pool is protected, the addresses already given out, will become
>> traps that get resolved through a lookup table that is built based on
>> the content of each allocation.
>>
>> That seems to generate a lot of overhead, not to mention the fact that
>> it might not play very well with the MMU.
> 
> That is effectively what i'm suggesting - as a form of protection for
> consumers against direct reads of data which may have been corrupted
> by some irrelevant means. In the context of pmalloc, it would probably
> be a separate type of ro+verified pool
ok, that seems more like an extension though.

ATM I am having problems gaining traction to get even the basic merged :-)

I would consider this as a possibility for future work, unless it is
said that it's necessary for pmalloc to be accepted ...

--
igor