linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: "Shi, Yang" <yang.shi@linaro.org>
To: akpm@linux-foundation.org, sfr@canb.auug.org.au,
	hughd@google.com, aryabinin@virtuozzo.com,
	trond.myklebust@primarydata.com, anna.schumaker@netapp.com
Cc: LKML <linux-kernel@vger.kernel.org>,
	linux-mm@kvack.org, linux-nfs@vger.kernel.org,
	yang.shi@linaro.org
Subject: [BUG linux-next] KASAN bug is raised on linux-next-20160414 with huge tmpfs on
Date: Wed, 20 Apr 2016 10:42:29 -0700	[thread overview]
Message-ID: <5717BF85.1090800@linaro.org> (raw)

Hi folks,

When I run the below test on my ARM64 machine with NFS mounted rootfs, I 
got KASAN bug report. The test runs well if mnt is not mounted with 
"huge=1".

# mount -t tmpfs -o huge=1 tmpfs /mnt
# cp -a /opt/ltp /mnt/

BUG: KASAN: use-after-free in nfs_readdir+0x2c4/0x848 at addr 
ffff80000b7f4000
Read of size 4 by task crond/446
page:ffff7bffc02dfd00 count:2 mapcount:0 mapping:ffff80001c2cae98 index:0x0
flags: 0x6c(referenced|uptodate|lru|active)
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff80002402da80
CPU: 0 PID: 446 Comm: crond Tainted: G        W 
4.6.0-rc3-next-20160414-WR8.0.0.0_standard+ #13
Hardware name: Freescale Layerscape 2085a RDB Board (DT)
Call trace:
[<ffff20000820bc90>] dump_backtrace+0x0/0x2b8
[<ffff20000820bf6c>] show_stack+0x24/0x30
[<ffff200008a28928>] dump_stack+0xb0/0xe8
[<ffff2000084c2cf0>] kasan_report_error+0x518/0x5c0
[<ffff2000084c32c0>] kasan_report+0x60/0x70
[<ffff2000084c1854>] __asan_load4+0x64/0x80
[<ffff20000868e1dc>] nfs_readdir+0x2c4/0x848
[<ffff2000085189d8>] iterate_dir+0x120/0x1d8
[<ffff2000085190dc>] SyS_getdents64+0xdc/0x170
[<ffff200008204ee0>] __sys_trace_return+0x0/0x4
Memory state around the buggy address:
  ffff80000b7f3f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff80000b7f3f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 >ffff80000b7f4000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                    ^
  ffff80000b7f4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff80000b7f4100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

BUG: KASAN: use-after-free in nfs_do_filldir+0x88/0x298 at addr 
ffff80000b7f4000
Read of size 4 by task crond/446
page:ffff7bffc02dfd00 count:2 mapcount:0 mapping:ffff80001c2cae98 index:0x0
flags: 0x6c(referenced|uptodate|lru|active)
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff80002402da80
CPU: 0 PID: 446 Comm: crond Tainted: G    B   W 
4.6.0-rc3-next-20160414-WR8.0.0.0_standard+ #13
Hardware name: Freescale Layerscape 2085a RDB Board (DT)
Call trace:
[<ffff20000820bc90>] dump_backtrace+0x0/0x2b8
[<ffff20000820bf6c>] show_stack+0x24/0x30
[<ffff200008a28928>] dump_stack+0xb0/0xe8
[<ffff2000084c2cf0>] kasan_report_error+0x518/0x5c0
[<ffff2000084c32c0>] kasan_report+0x60/0x70
[<ffff2000084c1854>] __asan_load4+0x64/0x80
[<ffff20000868cb98>] nfs_do_filldir+0x88/0x298
[<ffff20000868e3a0>] nfs_readdir+0x488/0x848
[<ffff2000085189d8>] iterate_dir+0x120/0x1d8
[<ffff2000085190dc>] SyS_getdents64+0xdc/0x170
[<ffff200008204ee0>] __sys_trace_return+0x0/0x4
Memory state around the buggy address:
  ffff80000b7f3f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff80000b7f3f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 >ffff80000b7f4000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                    ^
  ffff80000b7f4080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff80000b7f4100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

Thanks,
Yang

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

                 reply	other threads:[~2016-04-20 17:42 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

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=5717BF85.1090800@linaro.org \
    --to=yang.shi@linaro.org \
    --cc=akpm@linux-foundation.org \
    --cc=anna.schumaker@netapp.com \
    --cc=aryabinin@virtuozzo.com \
    --cc=hughd@google.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-nfs@vger.kernel.org \
    --cc=sfr@canb.auug.org.au \
    --cc=trond.myklebust@primarydata.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).