From: Jens Axboe <axboe@kernel.dk>
To: Pekka Enberg <penberg@kernel.org>
Cc: Xi Wang <xi.wang@gmail.com>,
Andrew Morton <akpm@linux-foundation.org>,
Dan Carpenter <dan.carpenter@oracle.com>,
linux-kernel@vger.kernel.org, Christoph Lameter <cl@linux.com>,
Matt Mackall <mpm@selenic.com>,
David Rientjes <rientjes@google.com>
Subject: Re: [PATCH RFC] slab: introduce knalloc/kxnalloc
Date: Thu, 09 Feb 2012 14:19:19 +0100 [thread overview]
Message-ID: <4F33C7D7.1060801@kernel.dk> (raw)
In-Reply-To: <CAOJsxLG0Lq7XZQWPxU=ut3Eec6UiRpwhsxU-k5Ooi7H1EBKT2A@mail.gmail.com>
On 02/09/2012 02:05 PM, Pekka Enberg wrote:
> On Thu, Feb 9, 2012 at 2:41 PM, Xi Wang <xi.wang@gmail.com> wrote:
>> This patch introduces knalloc/kxnalloc wrappers that perform integer
>> overflow checks without zeroing the memory.
>>
>> knalloc(n, size, flags) is the non-zeroing version of kcalloc(),
>> which allocates n * size bytes.
>>
>> kxnalloc(xsize, n, size, flags) allocates xsize + n * size bytes.
>> It is useful to allocate a structure ending with a zero-length array,
>> which is a commonly used pattern. For example, in posix_acl_alloc()
>> to allocate a posix_acl object one could call
>>
>> kxnalloc(sizeof(struct posix_acl),
>> count, sizeof(struct posix_acl_entry), flags);
>>
>> to avoid overflowing the allocation size.
>>
>> Suggested-by: Andrew Morton <akpm@linux-foundation.org>
>> Signed-off-by: Xi Wang <xi.wang@gmail.com>
>
> Are there really enough potential users to justify adding both?
Agree, lets not overdesign. kmalloc_array() sounds good to me, fwiw.
--
Jens Axboe
next prev parent reply other threads:[~2012-02-09 13:20 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-07 14:11 integer overflows in kernel/relay.c Dan Carpenter
2012-02-08 8:34 ` Jens Axboe
2012-02-08 22:25 ` Andrew Morton
2012-02-09 12:41 ` Jens Axboe
2012-02-09 17:39 ` Andrew Morton
2012-02-09 12:41 ` [PATCH RFC] slab: introduce knalloc/kxnalloc Xi Wang
2012-02-09 13:05 ` Pekka Enberg
2012-02-09 13:19 ` Jens Axboe [this message]
2012-02-09 13:26 ` Xi Wang
2012-02-09 13:48 ` [PATCH RFC v2] slab: introduce kmalloc_array Xi Wang
2012-02-09 22:42 ` David Rientjes
2012-02-09 23:08 ` Andrew Morton
2012-02-09 22:47 ` Jesper Juhl
2012-02-09 23:06 ` Andrew Morton
2012-02-09 23:43 ` Joe Perches
2012-02-13 15:08 ` Xi Wang
2012-02-13 16:01 ` Christoph Lameter
2012-02-13 19:44 ` Dan Carpenter
2012-02-13 20:27 ` Christoph Lameter
2012-02-14 7:20 ` Dan Carpenter
2012-02-14 7:35 ` Pekka Enberg
2012-02-14 11:12 ` Xi Wang
2012-02-14 15:02 ` Christoph Lameter
2012-02-14 16:30 ` Xi Wang
2012-02-14 16:34 ` Christoph Lameter
2012-02-14 16:43 ` Xi Wang
2012-02-14 19:33 ` Uninline kcalloc Christoph Lameter
2012-02-14 19:37 ` Christoph Lameter
2012-02-14 20:46 ` Andrew Morton
2012-02-14 20:50 ` Nick Bowler
2012-02-14 21:24 ` Christoph Lameter
2012-02-15 20:17 ` Nick Bowler
2012-02-15 20:24 ` Nick Bowler
2012-02-14 20:45 ` Andrew Morton
2012-02-14 20:58 ` Pekka Enberg
2012-02-14 21:09 ` Christoph Lameter
2012-02-14 21:31 ` Pekka Enberg
2012-02-14 21:38 ` Christoph Lameter
2012-02-14 21:46 ` Xi Wang
2012-02-14 22:08 ` Christoph Lameter
2012-02-15 19:14 ` Xi Wang
2012-02-15 19:34 ` Christoph Lameter
2012-02-16 3:10 ` Xi Wang
2012-02-16 14:51 ` Christoph Lameter
2012-02-16 18:32 ` Xi Wang
2012-02-16 20:47 ` Christoph Lameter
2012-02-10 13:09 ` [PATCH RFC v2] slab: introduce kmalloc_array Alexey Dobriyan
2012-02-10 13:11 ` Alexey Dobriyan
2012-02-10 13:55 ` Xi Wang
2012-02-10 13:58 ` Alexey Dobriyan
2012-02-10 14:09 ` Xi Wang
2012-02-11 12:19 ` Alexey Dobriyan
2012-02-12 5:46 ` Xi Wang
2012-02-09 12:56 ` integer overflows in kernel/relay.c Pekka Enberg
2012-02-09 10:44 ` [patch] relay: prevent integer overflow in relay_open() Dan Carpenter
2012-02-09 10:44 ` Dan Carpenter
2012-02-09 11:55 ` walter harms
2012-02-09 11:55 ` walter harms
2012-02-09 12:36 ` Dan Carpenter
2012-02-09 12:36 ` Dan Carpenter
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