2017-12-23 09:59:51

by Manfred Spraul

[permalink] [raw]
Subject: Re: BUG: unable to handle kernel paging request in ipcget

Hi,

On 12/23/2017 08:33 AM, 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.
>
Is one of the recent issues reproducible?
Either something is wrong with the faster ipc_get, or the improved
ipc_get makes issues in other areas visible.

--
    Manfred


2017-12-23 10:07:49

by Dmitry Vyukov

[permalink] [raw]
Subject: Re: BUG: unable to handle kernel paging request in ipcget

On Sat, Dec 23, 2017 at 10:59 AM, Manfred Spraul
<[email protected]> wrote:
> Hi,
>
> On 12/23/2017 08:33 AM, 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.
>>
> Is one of the recent issues reproducible?

Which one do you mean?
syzbot always provides up-to-date status of reproducers for all reported bugs.

> Either something is wrong with the faster ipc_get, or the improved ipc_get
> makes issues in other areas visible.
>
> --
> Manfred
>
> --
> You received this message because you are subscribed to the Google Groups
> "syzkaller" group.
> To unsubscribe from this group and stop receiving emails from it, send an
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>
> For more options, visit https://groups.google.com/d/optout.

2018-01-02 18:16:32

by Kees Cook

[permalink] [raw]
Subject: Re: BUG: unable to handle kernel paging request in ipcget

On Sat, Dec 23, 2017 at 2:07 AM, Dmitry Vyukov <[email protected]> wrote:
> On Sat, Dec 23, 2017 at 10:59 AM, Manfred Spraul
> <[email protected]> wrote:
>> Hi,
>>
>> On 12/23/2017 08:33 AM, 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.
>>>
>> Is one of the recent issues reproducible?
>
> Which one do you mean?
> syzbot always provides up-to-date status of reproducers for all reported bugs.
>
>> Either something is wrong with the faster ipc_get, or the improved ipc_get
>> makes issues in other areas visible.
>>
>> --
>> Manfred
>>
>> --
>> You received this message because you are subscribed to the Google Groups
>> "syzkaller" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to [email protected].
>>
>> For more options, visit https://groups.google.com/d/optout.

Was this report related to the recent set of kmalloc-1024 false positives?

-Kees

--
Kees Cook
Pixel Security

2018-01-07 11:19:50

by Dmitry Vyukov

[permalink] [raw]
Subject: Re: BUG: unable to handle kernel paging request in ipcget

On Tue, Jan 2, 2018 at 7:16 PM, Kees Cook <[email protected]> wrote:
> On Sat, Dec 23, 2017 at 2:07 AM, Dmitry Vyukov <[email protected]> wrote:
>> On Sat, Dec 23, 2017 at 10:59 AM, Manfred Spraul
>> <[email protected]> wrote:
>>> Hi,
>>>
>>> On 12/23/2017 08:33 AM, 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.
>>>>
>>> Is one of the recent issues reproducible?
>>
>> Which one do you mean?
>> syzbot always provides up-to-date status of reproducers for all reported bugs.
>>
>>> Either something is wrong with the faster ipc_get, or the improved ipc_get
>>> makes issues in other areas visible.
>
> Was this report related to the recent set of kmalloc-1024 false positives?


That's possible. It happened only twice and is unexplainable (right?). Let's do:

#syz fix: crypto: pcrypt - fix freeing pcrypt instances

and see if this happens again after the commit lands.