From: Sasha Levin <sasha.levin@oracle.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dave Jones <davej@redhat.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Pekka Enberg <penberg@kernel.org>,
Christoph Lameter <cl@linux.com>, linux-mm <linux-mm@kvack.org>
Subject: Re: slub error in fs/sysfs/bin.c related code
Date: Thu, 28 Feb 2013 12:00:07 -0500 [thread overview]
Message-ID: <512F8D17.3010302@oracle.com> (raw)
In-Reply-To: <20130228162735.GB26013@kroah.com>
On 02/28/2013 11:27 AM, Greg Kroah-Hartman wrote:
> On Thu, Feb 28, 2013 at 11:03:58AM -0500, Sasha Levin wrote:
>> Hi Greg,
>>
>> While fuzzing with trinity inside a KVM tools guest, running latest -next kernel
>> I got the following spew.
>>
>> The open() and release() callbacks in the traces below point to fs/sysfs/bin.c.
>
> Any hint as to which sysfs binary file you were accessing when this
> happened?
No, sorry - the trace only shows the allocation and freeing, I'm not sure
which file it was.
>> [ 719.288925] =============================================================================
>> [ 719.290663] BUG kmalloc-4096 (Tainted: G W ): Redzone overwritten
>> [ 719.291764] -----------------------------------------------------------------------------
>> [ 719.291764]
>> [ 719.294527] Disabling lock debugging due to kernel taint
>> [ 719.294527] INFO: 0xffff88006d1a5520-0xffff88006d1a5520. First byte 0x0 instead of 0xcc
>> [ 719.294527] INFO: Allocated in open+0xb8/0x190 age=18922 cpu=1 pid=7095
>> [ 719.294527] __slab_alloc+0x622/0x6d0
>> [ 719.294527] kmem_cache_alloc_trace+0x123/0x2c0
>> [ 719.294527] open+0xb8/0x190
>> [ 719.294527] do_dentry_open+0x229/0x330
>> [ 719.294527] finish_open+0x54/0x70
>> [ 719.294527] do_last+0x56c/0x790
>> [ 719.294527] path_openat+0xbe/0x490
>> [ 719.294527] do_filp_open+0x44/0xa0
>> [ 719.294527] do_sys_open+0x133/0x1d0
>> [ 719.294527] sys_open+0x1c/0x20
>> [ 719.294527] tracesys+0xdd/0xe2
>> [ 719.294527] INFO: Freed in seq_release+0x18/0x30 age=18947 cpu=0 pid=31203
>> [ 719.294527] __slab_free+0x3c/0x590
>> [ 719.294527] kfree+0x2cb/0x2e0
>> [ 719.294527] seq_release+0x18/0x30
>> [ 719.294527] single_release+0x24/0x40
>> [ 719.294527] proc_reg_release+0xed/0x110
>> [ 719.294527] __fput+0x122/0x2d0
>> [ 719.294527] ____fput+0x9/0x10
>> [ 719.294527] task_work_run+0xbe/0x100
>> [ 719.294527] do_notify_resume+0x7e/0xa0
>> [ 719.294527] int_signal+0x12/0x17
>> [ 719.294527] INFO: Slab 0xffffea0001b46800 objects=7 used=7 fp=0x (null) flags=0x1ffc0000004081
>> [ 719.294527] INFO: Object 0xffff88006d1a4520 @offset=17696 fp=0x (null)
>
> Hm, where is sysfs in this traceback? I don't see it mentioned anywhere
> in this report, what am I missing?
The call trace at the end of the spew:
[ 719.294527] Call Trace:
[ 719.294527] [<ffffffff81260202>] print_trailer+0x132/0x140
[ 719.294527] [<ffffffff81260641>] check_bytes_and_report+0xe1/0x130
[ 719.294527] [<ffffffff812626e2>] check_object+0x52/0x220
[ 719.294527] [<ffffffff81263a13>] free_debug_processing+0x173/0x300
[ 719.294527] [<ffffffff8130c9a2>] ? release+0x72/0x90
[ 719.294527] [<ffffffff8130c9a2>] ? release+0x72/0x90
[ 719.294527] [<ffffffff812674ec>] __slab_free+0x3c/0x590
[ 719.294527] [<ffffffff8118541d>] ? trace_hardirqs_on+0xd/0x10
[ 719.294527] [<ffffffff83d7a284>] ? _raw_spin_unlock_irqrestore+0x94/0xc0
[ 719.294527] [<ffffffff81a3898f>] ? __debug_check_no_obj_freed+0x15f/0x220
[ 719.294527] [<ffffffff83d75e89>] ? mutex_unlock+0x9/0x10
[ 719.294527] [<ffffffff8130c9a2>] ? release+0x72/0x90
[ 719.294527] [<ffffffff8130c9a2>] ? release+0x72/0x90
[ 719.294527] [<ffffffff81267d0b>] kfree+0x2cb/0x2e0
[ 719.294527] [<ffffffff8130c9a2>] release+0x72/0x90
[ 719.294527] [<ffffffff81289592>] __fput+0x122/0x2d0
[ 719.294527] [<ffffffff812897a9>] ____fput+0x9/0x10
[ 719.294527] [<ffffffff81135bbe>] task_work_run+0xbe/0x100
[ 719.294527] [<ffffffff81114781>] do_exit+0x311/0x510
[ 719.294527] [<ffffffff81114a21>] do_group_exit+0xa1/0xe0
[ 719.294527] [<ffffffff81114a72>] sys_exit_group+0x12/0x20
[ 719.294527] [<ffffffff83d833d0>] tracesys+0xdd/0xe2
Specifically, this:
[ 719.294527] [<ffffffff8130c9a2>] release+0x72/0x90
Is the release() in fs/sysfs/bin.c
I've confirmed it by also checking the sizes of the open() and
release() sizes and actual code at those positions mentioned
in the backtrace, and they match the backtrace.
Thanks,
Sasha
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prev parent reply other threads:[~2013-02-28 16:59 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-28 16:03 slub error in fs/sysfs/bin.c related code Sasha Levin
2013-02-28 16:27 ` Greg Kroah-Hartman
2013-02-28 17:00 ` Sasha Levin [this message]
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