From: Qingfang Deng <qingfang.deng@linux.dev>
To: Eric Dumazet <edumazet@google.com>, Jaeyoung Chung <jjy600901@snu.ac.kr>
Cc: andrew+netdev@lunn.ch, davem@davemloft.net, kuba@kernel.org,
netdev@vger.kernel.org, pabeni@redhat.com, 726ksm@gmail.com,
kees@kernel.org, linux-kernel@vger.kernel.org,
eulgyukim@snu.ac.kr
Subject: Re: [BUG] KASAN: slab-use-after-free Read in slip_receive_buf
Date: Wed, 26 Aug 2026 13:38:02 +0800 [thread overview]
Message-ID: <8ea9c9ce-e1ed-475b-90d3-abf1bd86c3d7@linux.dev> (raw)
In-Reply-To: <CANn89iJE_HosLBRhZGM-GVpgPCSNtHiS9vnCc3tEmTVaamcJ9g@mail.gmail.com>
Hi,
On 2026/8/25 23:27, Eric Dumazet wrote:
> On Tue, Aug 25, 2026 at 5:07 PM Jaeyoung Chung <jjy600901@snu.ac.kr> wrote:
>> Hello,
>>
>> We found a "KASAN: slab-use-after-free Read in slip_receive_buf" on Linux v7.2.
>> The issue was found by our own race fuzzer. We have not analyzed the root cause,
>> so we do not have a proposed fix to offer.
>>
>> To reproduce the race reliably, we applied the delay patch below to the
>> kernel and ran the C reproducer as root inside an x86_64 QEMU guest. The
>> crash log we observed, the delay patch and the reproducer are all included
>> below.
>>
>> The following kernel config options are required to reproduce the issue:
>> CONFIG_SLIP=y
>> CONFIG_LEGACY_TIOCSTI=y
>> CONFIG_UNIX98_PTYS=y
>> CONFIG_TTY=y
>> CONFIG_KASAN=y
>>
>> We hope this report is useful. Please let us know if any further
>> information would help.
>>
>> Reported-by: Eulgyu Kim <eulgyukim@snu.ac.kr>
>> Reported-by: Jaeyoung Chung <jjy600901@snu.ac.kr>
> This rings a bell; I had a local syzbot report for this issue a while back.
>
> I think we should remove slip_hangup().
ppp_async.c and ppp_synctty.c have the same anti-pattern. Should we
remove theirs as well?
next prev parent reply other threads:[~2026-08-26 5:38 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-25 15:06 [BUG] KASAN: slab-use-after-free Read in slip_receive_buf Jaeyoung Chung
2026-08-25 15:27 ` Eric Dumazet
2026-08-26 5:38 ` Qingfang Deng [this message]
2026-08-26 5:46 ` Eric Dumazet
2026-08-26 5:53 ` Qingfang Deng
2026-08-26 6:14 ` Eric Dumazet
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