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Subject: Re: [RFC PATCH v2 0/2] Randomization of address chosen by mmap.
From:   Ilya Smith <blackzert@gmail.com>
In-Reply-To: <20180330075508.GA21798@amd>
Date:   Fri, 30 Mar 2018 12:07:58 +0300
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 <20180330075508.GA21798@amd>
To:     Pavel Machek <pavel@ucw.cz>
Sender: linux-kernel-owner@vger.kernel.org
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Hi

> On 30 Mar 2018, at 10:55, Pavel Machek <pavel@ucw.cz> wrote:
>=20
> Hi!
>=20
>> Current implementation doesn't randomize address returned by mmap.
>> All the entropy ends with choosing mmap_base_addr at the process
>> creation. After that mmap build very predictable layout of address
>> space. It allows to bypass ASLR in many cases. This patch make
>> randomization of address on any mmap call.
>=20
> How will this interact with people debugging their application, and
> getting different behaviours based on memory layout?
>=20
> strace, strace again, get different results?
>=20

Honestly I=E2=80=99m confused about your question. If the only one way =
for debugging=20
application is to use predictable mmap behaviour, then something went =
wrong in=20
this live and we should stop using computers at all.

Thanks,
Ilya