linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andrey Ryabinin <aryabinin@virtuozzo.com>
To: Walter Wu <walter-zh.wu@mediatek.com>,
	Alexander Potapenko <glider@google.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Matthias Brugger <matthias.bgg@gmail.com>
Cc: kasan-dev@googlegroups.com, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	wsd_upstream <wsd_upstream@mediatek.com>,
	linux-mediatek@lists.infradead.org,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH v4 1/2] kasan: detect negative size in memory operation function
Date: Fri, 22 Nov 2019 01:20:23 +0300	[thread overview]
Message-ID: <b2ba5228-dec0-9acf-49e9-d57f156814ef@virtuozzo.com> (raw)
In-Reply-To: <20191112065302.7015-1-walter-zh.wu@mediatek.com>



On 11/12/19 9:53 AM, Walter Wu wrote:
> KASAN missed detecting size is a negative number in memset(), memcpy(),
> and memmove(), it will cause out-of-bounds bug. So needs to be detected
> by KASAN.
> 
> If size is a negative number, then it has a reason to be defined as
> out-of-bounds bug type.
> Casting negative numbers to size_t would indeed turn up as
> a large size_t and its value will be larger than ULONG_MAX/2,
> so that this can qualify as out-of-bounds.
> 
> KASAN report is shown below:
> 
>  BUG: KASAN: out-of-bounds in kmalloc_memmove_invalid_size+0x70/0xa0
>  Read of size 18446744073709551608 at addr ffffff8069660904 by task cat/72
> 
>  CPU: 2 PID: 72 Comm: cat Not tainted 5.4.0-rc1-next-20191004ajb-00001-gdb8af2f372b2-dirty #1
>  Hardware name: linux,dummy-virt (DT)
>  Call trace:
>   dump_backtrace+0x0/0x288
>   show_stack+0x14/0x20
>   dump_stack+0x10c/0x164
>   print_address_description.isra.9+0x68/0x378
>   __kasan_report+0x164/0x1a0
>   kasan_report+0xc/0x18
>   check_memory_region+0x174/0x1d0
>   memmove+0x34/0x88
>   kmalloc_memmove_invalid_size+0x70/0xa0
> 
> [1] https://bugzilla.kernel.org/show_bug.cgi?id=199341
> 
> Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
> Reported-by: Dmitry Vyukov <dvyukov@google.com>
> Suggested-by: Dmitry Vyukov <dvyukov@google.com>
> Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
> Cc: Alexander Potapenko <glider@google.com>
> Reported-by: kernel test robot <lkp@intel.com>
> ---

Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>

  parent reply	other threads:[~2019-11-21 22:22 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-12  6:53 [PATCH v4 1/2] kasan: detect negative size in memory operation function Walter Wu
2019-11-20  8:34 ` Walter Wu
2019-11-21 12:26 ` Andrey Ryabinin
2019-11-21 13:02   ` Walter Wu
2019-11-21 13:03     ` Andrey Ryabinin
2019-11-21 13:09       ` Walter Wu
2019-11-21 19:58   ` Dmitry Vyukov
2019-11-21 22:18     ` Andrey Ryabinin
2019-11-21 22:20 ` Andrey Ryabinin [this message]
2019-11-22  7:18   ` Walter Wu

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=b2ba5228-dec0-9acf-49e9-d57f156814ef@virtuozzo.com \
    --to=aryabinin@virtuozzo.com \
    --cc=akpm@linux-foundation.org \
    --cc=dvyukov@google.com \
    --cc=glider@google.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mediatek@lists.infradead.org \
    --cc=linux-mm@kvack.org \
    --cc=matthias.bgg@gmail.com \
    --cc=walter-zh.wu@mediatek.com \
    --cc=wsd_upstream@mediatek.com \
    /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).