Re: WARNING in sysfs_warn_dup

From: Dmitry Vyukov
Date: Tue Dec 19 2017 - 04:07:13 EST


On Tue, Dec 19, 2017 at 10:03 AM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote:
>
> On Tue, Dec 19, 2017 at 10:01 AM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>>
>> On Mon, Dec 18, 2017 at 08:57:01AM -0800, syzbot wrote:
>> > Hello,
>> >
>> > syzkaller hit the following crash on
>> > 6084b576dca2e898f5c101baef151f7bfdbb606d
>> > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master
>> > compiler: gcc (GCC) 7.1.1 20170620
>> > .config is attached
>> > Raw console output is attached.
>> >
>> > Unfortunately, I don't have any reproducer for this bug yet.
>> >
>> >
>> > netlink: 9 bytes leftover after parsing attributes in process
>> > `syz-executor3'.
>> > sg_write: data in/out 822404280/197 bytes for SCSI command 0x12-- guessing
>> > data in;
>> > program syz-executor0 not setting count and/or reply_len properly
>> > sg_write: data in/out 262364/161 bytes for SCSI command 0xff-- guessing data
>> > in;
>> > program syz-executor0 not setting count and/or reply_len properly
>> > WARNING: CPU: 1 PID: 22282 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x60/0x80
>> > fs/sysfs/dir.c:30
>> > Kernel panic - not syncing: panic_on_warn set ...
>>
>> Looks like a networking issue, it tried to create two sysfs directories
>> with the same name, which isn't a sysfs bug :)


Now as plain text:

+net/core/dev.c maintainers

Let's keep the footer as well, so that people know how to handle this report:

---
This bug is generated by a dumb bot. It may contain errors.
See https://goo.gl/tpsmEJ for details.
Direct all questions to syzkaller@xxxxxxxxxxxxxxxxx
Please credit me with: Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx>

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