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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: <20180327221635.GA3790@thunk.org>
Date:   Wed, 28 Mar 2018 21:48:22 +0300
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To:     "Theodore Y. Ts'o" <tytso@mit.edu>
Sender: linux-kernel-owner@vger.kernel.org
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> On 28 Mar 2018, at 01:16, Theodore Y. Ts'o <tytso@mit.edu> wrote:
>=20
> On Tue, Mar 27, 2018 at 04:51:08PM +0300, Ilya Smith wrote:
>>> /dev/[u]random is not sufficient?
>>=20
>> Using /dev/[u]random makes 3 syscalls - open, read, close. This is a =
performance
>> issue.
>=20
> You may want to take a look at the getrandom(2) system call, which is
> the recommended way getting secure random numbers from the kernel.
>=20
>>> Well, I am pretty sure userspace can implement proper free ranges
>>> tracking=E2=80=A6
>>=20
>> I think we need to know what libc developers will say on implementing =
ASLR in=20
>> user-mode. I am pretty sure they will say =E2=80=98nether=E2=80=99 or =
=E2=80=98some-day=E2=80=99. And problem=20
>> of ASLR will stay forever.
>=20
> Why can't you send patches to the libc developers?
>=20
> Regards,
>=20
> 						- Ted

I still believe the issue is on kernel side, not in library.

Best regards,
Ilya