[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <CAGXu5j+0WKjetgxxdE4HUi9mDjnWm+taNLnYio1VgpAeCutpJg@mail.gmail.com>
Date: Thu, 10 May 2018 17:02:34 -0700
From: Kees Cook <keescook@...omium.org>
To: Linux-MM <linux-mm@...ck.org>
Cc: Rasmus Villemoes <linux@...musvillemoes.dk>, Matthew Wilcox <mawilcox@...rosoft.com>,
Matthew Wilcox <willy@...radead.org>, LKML <linux-kernel@...r.kernel.org>,
Kernel Hardening <kernel-hardening@...ts.openwall.com>
Subject: Re: [PATCH v2 0/6] Provide saturating helpers for allocation
On Wed, May 9, 2018 at 1:02 PM, Kees Cook <keescook@...omium.org> wrote:
> This is a stab at providing three new helpers for allocation size
> calculation:
>
> struct_size(), array_size(), and array3_size().
>
> These are implemented on top of Rasmus's overflow checking functions. The
> existing allocators are adjusted to use the more efficient overflow
> checks as well.
>
> I have left out the 8 tree-wide conversion patches of open-coded
> multiplications into the new helpers, as those are largely
> unchanged from v1. Everything can be seen here, though:
> https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git/log/?h=kspp/overflow/array_size
>
> The question remains for what to do with the *calloc() and *_array*()
> API. They could be entirely removed in favor of using the new helpers:
>
> kcalloc(n, size, gfp) -> kzalloc(array_size(n, size), gfp)
> kmalloc_array(n, size, gfp) -> kmalloc(array_size(n, size), gfp)
>
> Changes from v1:
> - use explicit overflow helpers instead of array_size() helpers.
> - drop early-checks for SIZE_MAX.
> - protect devm_kmalloc()-family from addition overflow.
> - added missing overflow.h includes.
> - fixed 0-day issues in a few treewide manual conversions
I've added an allocation overflow addition to lib/test_overflow now,
so I'll send a v3 soon. Does anyone want to provide an Ack or Reviewed
for these?
Also, any thoughts on *calloc() and *_array*() removal?
-Kees
--
Kees Cook
Pixel Security
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.
