Re: KASAN: use-after-free Read in cma_cancel_operation, rdma_listen

From: Haakon Bugge
Date: Tue Apr 13 2021 - 10:09:41 EST




> On 13 Apr 2021, at 15:44, Jason Gunthorpe <jgg@xxxxxxxx> wrote:
>
> On Tue, Apr 13, 2021 at 09:42:43PM +0800, Hao Sun wrote:
>> Jason Gunthorpe <jgg@xxxxxxxx> 于2021年4月13日周二 下午9:34写道:
>>>
>>> On Tue, Apr 13, 2021 at 11:36:41AM +0800, Hao Sun wrote:
>>>> Hi
>>>>
>>>> When using Healer(https://github.com/SunHao-0/healer/tree/dev) to fuzz
>>>> the Linux kernel, I found two use-after-free bugs which have been
>>>> reported a long time ago by Syzbot.
>>>> Although the corresponding patches have been merged into upstream,
>>>> these two bugs can still be triggered easily.
>>>> The original information about Syzbot report can be found here:
>>>> https://syzkaller.appspot.com/bug?id=8dc0bcd9dd6ec915ba10b3354740eb420884acaa
>>>> https://syzkaller.appspot.com/bug?id=95f89b8fb9fdc42e28ad586e657fea074e4e719b
>>>
>>> Then why hasn't syzbot seen this in a year's time? Seems strange
>>>
>>
>> Seems strange to me too, but the fact is that the reproduction program
>> in attachment can trigger these two bugs quickly.
>
> Do you have this in the C format?

How can a commit changing arch m68k provoke a bug when running on x86_64?


Håkon

>
> Jason