linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
To: cl@linux.com
Cc: glommer@parallels.com, penberg@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [linux-next-20130422] Bug in SLAB?
Date: Tue, 7 May 2013 19:38:12 +0900	[thread overview]
Message-ID: <201305071938.DAC81273.HOSJOFFOQLtMFV@I-love.SAKURA.ne.jp> (raw)
In-Reply-To: <0000013e7a18153d-4b59eaf6-0fcd-4eec-b357-31d3d40baa7d-000000@email.amazonses.com>

Christoph Lameter wrote:
> On Sat, 4 May 2013, Tetsuo Handa wrote:
> 
> > Christoph Lameter wrote:
> > > Ok could I see the kernel logs with the warnings?
> > Sure.
> 
> These are exclusively from the module load. So the kernel seems to be
> clean of large kmalloc's ?
> 
There are modules (e.g. TOMOYO) which do not check for KMALLOC_MAX_SIZE limit
and expect kmalloc() larger than KMALLOC_MAX_SIZE bytes to return NULL.

As far as I know, such modules sequentially double the buffer size. Therefore,
as long as request for KMALLOC_MAX_SIZE * 2 bytes returns NULL, they won't
trigger oops by requesting for KMALLOC_MAX_SIZE * 8 bytes.

The testcase I wrote is for module (I don't know if there is one) which
requests for KMALLOC_MAX_SIZE * 8 bytes without requesting for
KMALLOC_MAX_SIZE * 2 bytes and/or KMALLOC_MAX_SIZE * 4 bytes.

  reply	other threads:[~2013-05-07 10:38 UTC|newest]

Thread overview: 55+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-04-24 12:08 [linux-next-20130422] Bug in bootup code or debug code? Tetsuo Handa
2013-04-25 12:20 ` [linux-next-20130422] Bug in SLAB? Tetsuo Handa
2013-04-29  2:40   ` Tetsuo Handa
2013-04-29 10:12     ` Pekka Enberg
2013-04-29 14:44       ` Glauber Costa
2013-04-29 14:59         ` Christoph Lameter
2013-04-29 15:16           ` Glauber Costa
2013-04-29 15:46             ` Christoph Lameter
2013-04-29 15:54               ` Glauber Costa
2013-04-29 15:28           ` Tetsuo Handa
2013-04-29 16:16             ` Tetsuo Handa
2013-05-09 12:25               ` Tetsuo Handa
2013-05-09 14:14                 ` Christoph Lameter
2013-05-09 21:54                   ` Tetsuo Handa
2013-05-10 12:38                     ` Tetsuo Handa
2013-05-10 15:57                       ` Christoph Lameter
     [not found]                         ` <201305272153.HEH51089.OHFQMOOtFLSFVJ@I-love.SAKURA.ne.jp>
2013-06-17 11:59                           ` Tetsuo Handa
2013-04-29 17:48             ` Christoph Lameter
2013-04-29 21:45               ` Tetsuo Handa
2013-04-30 14:26                 ` Christoph Lameter
2013-04-30 16:01                   ` Tetsuo Handa
2013-04-30 17:27                     ` Christoph Lameter
2013-05-01  8:05                       ` Pekka Enberg
2013-05-02 15:12                         ` Christoph Lameter
2013-05-01 12:14                       ` Tetsuo Handa
2013-05-02 11:51                         ` Tetsuo Handa
2013-05-02 20:53                         ` Christoph Lameter
2013-05-03  8:26                           ` Tetsuo Handa
2013-05-03 15:43                             ` Christoph Lameter
2013-05-06  6:59                               ` Geert Uytterhoeven
2013-05-06  7:27                                 ` Pekka Enberg
2013-05-03 18:04                             ` Christoph Lameter
2013-05-03 18:48                               ` Tetsuo Handa
2013-05-03 19:21                                 ` Christoph Lameter
2013-05-04  0:15                                   ` Tetsuo Handa
2013-05-06 13:46                                     ` Christoph Lameter
2013-05-07 10:38                                       ` Tetsuo Handa [this message]
2013-05-07 14:28                                         ` Christoph Lameter
2013-07-01 20:09                                           ` Andrew Morton
2013-07-01 21:45                                             ` Tetsuo Handa
2013-07-01 21:53                                               ` Andrew Morton
2013-07-02 12:49                                                 ` Tetsuo Handa
2013-07-02 19:12                                                   ` Andrew Morton
2013-07-07 15:58                                                     ` Pekka Enberg
2013-05-06  6:32                               ` Pekka Enberg
2013-05-06 13:47                                 ` Christoph Lameter
2013-05-06 20:24                               ` Pekka Enberg
2013-05-07 14:23                                 ` Christoph Lameter
2013-05-07 14:44                                   ` Pekka Enberg
2013-05-07 15:40                                     ` Christoph Lameter
2013-04-30 14:34                 ` Christoph Lameter
2013-05-01  8:03                   ` Pekka Enberg
2013-05-02 15:13                     ` Christoph Lameter
2013-04-30 15:16                 ` Fix off by one error in slab.h Christoph Lameter
2013-04-29  2:56   ` [linux-next-20130422] Bug in SLAB? Zhan Jianyu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=201305071938.DAC81273.HOSJOFFOQLtMFV@I-love.SAKURA.ne.jp \
    --to=penguin-kernel@i-love.sakura.ne.jp \
    --cc=cl@linux.com \
    --cc=glommer@parallels.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=penberg@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).