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From:   Alexander Potapenko <glider@google.com>
Date:   Fri, 30 Jun 2023 12:10:25 +0200
Message-ID: <CAG_fn=X+eU=-WLXASidBCHWS3L7RvtN=mx3Bj8GD9GcA=Htf2w@mail.gmail.com>
Subject: Re: [PATCH] net: tls: enable __GFP_ZERO upon tls_init()
To:     Ard Biesheuvel <ardb@kernel.org>
Cc:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        Boris Pismenny <borisp@nvidia.com>,
        John Fastabend <john.fastabend@gmail.com>,
        Jakub Kicinski <kuba@kernel.org>, herbert@gondor.apana.org.au,
        linux-crypto@vger.kernel.org, syzkaller-bugs@googlegroups.com,
        syzbot <syzbot+828dfc12440b4f6f305d@syzkaller.appspotmail.com>,
        Eric Biggers <ebiggers@kernel.org>,
        Aviad Yehezkel <aviadye@nvidia.com>,
        Daniel Borkmann <daniel@iogearbox.net>, netdev@vger.kernel.org,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>
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On Fri, Jun 30, 2023 at 12:02=E2=80=AFPM Ard Biesheuvel <ardb@kernel.org> w=
rote:
>
> On Fri, 30 Jun 2023 at 11:53, Tetsuo Handa
> <penguin-kernel@i-love.sakura.ne.jp> wrote:
> >
> > On 2023/06/30 18:36, Ard Biesheuvel wrote:
> > > Why are you sending this now?
> >
> > Just because this is currently top crasher and I can reproduce locally.
> >
> > > Do you have a reproducer for this issue?
> >
> > Yes. https://syzkaller.appspot.com/text?tag=3DReproC&x=3D12931621900000=
 works.
> >
>
> Could you please share your kernel config and the resulting kernel log
> when running the reproducer? I'll try to reproduce locally as well,
> and see if I can figure out what is going on in the crypto layer

The config together with the repro is available at
https://syzkaller.appspot.com/bug?extid=3D828dfc12440b4f6f305d, see the
latest row of the "Crashes" table that contains a C repro.
Config: https://syzkaller.appspot.com/text?tag=3DKernelConfig&x=3Dee5f7a0b2=
e48ed66
Report: https://syzkaller.appspot.com/text?tag=3DCrashReport&x=3D1325260d90=
0000
Syz repro: https://syzkaller.appspot.com/text?tag=3DReproSyz&x=3D11af973e90=
0000
C repro: https://syzkaller.appspot.com/text?tag=3DReproC&x=3D163a1e45900000

The bug is reproducible for me locally as well (and Tetsuo's patch
makes it disappear, although I have no opinion on its correctness).