[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <0100016a59ffa618-56d49996-ecb0-481c-88c3-380495651623-000000@email.amazonses.com>
Date: Fri, 26 Apr 2019 14:14:47 +0000
From: Christopher Lameter <cl@...ux.com>
To: Alexander Potapenko <glider@...gle.com>
cc: akpm@...ux-foundation.org, dvyukov@...gle.com, keescook@...omium.org,
labbott@...hat.com, linux-mm@...ck.org,
linux-security-module@...r.kernel.org, kernel-hardening@...ts.openwall.com
Subject: Re: [PATCH 1/3] mm: security: introduce the init_allocations=1 boot
option
On Thu, 18 Apr 2019, Alexander Potapenko wrote:
> This option adds the possibility to initialize newly allocated pages and
> heap objects with zeroes. This is needed to prevent possible information
> leaks and make the control-flow bugs that depend on uninitialized values
> more deterministic.
>
> Initialization is done at allocation time at the places where checks for
> __GFP_ZERO are performed. We don't initialize slab caches with
> constructors to preserve their semantics. To reduce runtime costs of
> checking cachep->ctor we replace a call to memset with a call to
> cachep->poison_fn, which is only executed if the memory block needs to
> be initialized.
Just check for a ctor and then zero or use whatever pattern ? Why add a
new function?
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
