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Date:   Wed, 17 May 2023 14:19:31 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     yang lan <lanyang0908@gmail.com>
Cc:     axboe@kernel.dk, sashal@kernel.org, asml.silence@gmail.com,
        dylany@fb.com, linux-kernel@vger.kernel.org,
        io-uring@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: Re: [Bug report] kernel panic: System is deadlocked on memory
Message-ID: <2023051752-strategy-aorta-cf01@gregkh>
References: <CAAehj2kcgtRta0ou6KQiyz33O4hf+_7jgndzV_neyQRj5BjSJQ@mail.gmail.com>
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On Wed, May 17, 2023 at 08:02:38PM +0800, yang lan wrote:
> Hi,
> 
> We use our modified Syzkaller to fuzz the Linux kernel and found the
> following issue:
> 
> Head Commit: f1b32fda06d2cfb8eea9680b0ba7a8b0d5b81eeb
> Git Tree: stable
> 
> Console output: https://pastebin.com/raw/Ssz6eVA6
> Kernel config: https://pastebin.com/raw/BiggLxRg
> C reproducer: https://pastebin.com/raw/tM1iyfjr
> Syz reproducer: https://pastebin.com/raw/CEF1R2jg
> 
> root@syzkaller:~# uname -a
> Linux syzkaller 5.10.179 #5 SMP PREEMPT Mon May 1 23:59:32 CST 2023

Does this also happen on 6.4-rc2?


> x86_64 GNU/Linux
> root@syzkaller:~# gcc poc_io_uring_enter.c -o poc_io_uring_enter
> root@syzkaller:~# ./poc_io_uring_enter
> ...
> [  244.945440][ T3106]
> oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0-1,global_oom,task_memcg=/,task=dhclient,pid=4526,uid=0
> [  244.946537][ T3106] Out of memory: Killed process 4526 (dhclient)

Is this using fault injection, or a normal operation?

thanks,

greg k-h