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boundary="000000000000e5630306003ad243" X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 7C5F51A0010 X-Stat-Signature: cjurrkirfp1jsozogdguuyahc4hc6iy9 X-Rspam-User: X-HE-Tag: 1689102510-565359 X-HE-Meta: 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 fyAf6Flf 1OT4rpkRzVWwhq9CjtxaPSwUQfMoMv8PCxvRANhCpJ57jYZf4dTD6zyAtapz49W3JaN12riMkJzaExy68sqt3v3ShFqbmP28MFRFzCyKmJCti4vj4Nqx4+WOXfzih91Df8JTHo74zug4edHOd4razsGNfY8XiGFKuINNMX1cbThKka7J1wE2aBR6O49ZxV+KE0EFBPYYmzFHdBfGyF9tX+ep6ka37bMqOos0puLexm2G5J5dePCTOGuWq/kdb9KxQDN6do2DBxoWrOAovxaNNuFbnan8NRVncmcdP893eThRlMNRk7HyXhqtJOiGj6m/ox1MUHOu0YYviHZR56J15CqgcB0pXZC6BKH/5kCWF0SIH92GsYMcq2FtNjFqwdAMSCSYdqhawZQFXcz0LZbePF5ftPF+yoQgQzmgDYbcg/fYUhOIkzKAXWArbi5fpRmknO1k0t+YaBwuK45lnCGlcUarhcM9EtiY3arNO6EQyv73NkQ61s06pWvUk+BbxTP9PUV9ozMKtHV3RMiFrhIyPxO25zooVVTZ3L/i8JxGwUsX/wm4CGAuvF4d4cDJZew2uAAI4Lnixg9Cb5VwdOYSAGKPX2FXIpkhZx/BQ61UGGlOM2Gf/J3ohJoIx4Tz8wUKqfjyne1GKSEhKsgBK8qcVPdBzU9zdnu32cGFmKjwYn3OyLERcm1W7pc/7ig/UfWP/Lx7DWd8AvvHFVpHa5meUYBltZvaYtpWYyMv+emQwWdqcHFHGzoyz13AcP/D2arJlxjNWnbDepjlCkmU= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: --000000000000e5630306003ad243 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Thanks for confirming! On Tue, Jul 11, 2023 at 9:26=E2=80=AFAM Kees Cook w= rote: > On Tue, Jul 11, 2023 at 09:15:00AM -0700, Sean Christopherson wrote: > > On Mon, Jul 10, 2023, Andrew Morton wrote: > > > On Sun, 9 Jul 2023 14:32:09 -0700 Zheng Zhang < > zheng.zhang@email.ucr.edu> wrote: > > > > > > > Kees, Andrew, and to whom it may concern: > > > > > > > > Hello! We have found a bug in the Linux kernel version 6.2.0 by > syzkaller > > > > with our own templates. It also produces a POC. > > > > Attached is the report, log, and reproducers generated by syzkaller > > > > Please let me know if there is any additional information that I ca= n > > > > provide to help debug this issue. > > > > Thanks! > > > > > > Let's cc the kvm mailing list. > > > > > > Original email is at > > > > https://lkml.kernel.org/r/CAC_GQSr3xzZaeZt85k_RCBd5kfiOve8qXo7a81Cq53LuVQ= 5r=3DQ@mail.gmail.com > > > > Yeaaaah. We failed kernel programming 101. KVM installs file > descriptors to > > let userspace read VM and vCPU stats, but doesn't grab a reference to > the VM to > > ensure the VM and its vCPUs are kept alive until the stats fds are > closed. I'll > > send a patch. > > Thanks! Another victory for hardened usercopy. :) > > -- > Kees Cook > --000000000000e5630306003ad243 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Thanks for confirming!

On Tue, Jul 11, 2023 at 9:26=E2=80= =AFAM Kees Cook <keescook@chrom= ium.org> wrote:
On Tue, Jul 11, 2023 at 09:15:00AM -0700, Sean Christopherson wrote:=
> On Mon, Jul 10, 2023, Andrew Morton wrote:
> > On Sun, 9 Jul 2023 14:32:09 -0700 Zheng Zhang <zheng.zhang@email.ucr.edu> wrote:
> >
> > > Kees, Andrew, and=C2=A0 to whom it may concern:
> > >
> > > Hello! We have found a bug in the Linux kernel version 6.2.0= by syzkaller
> > > with our own templates. It also produces a POC.
> > > Attached is the report, log, and reproducers generated by sy= zkaller
> > > Please let me know if there is any additional information th= at I can
> > > provide to help debug this issue.
> > > Thanks!
> >
> > Let's cc the kvm mailing list.
> >
> > Original email is at
> > https://lkml.kernel.org/r/CAC_GQSr3xzZaeZt85k_RCBd5kfiOve8qXo7a81Cq53Lu= VQ5r=3DQ@mail.gmail.com
>
> Yeaaaah.=C2=A0 We failed kernel programming 101.=C2=A0 KVM installs fi= le descriptors to
> let userspace read VM and vCPU stats, but doesn't grab a reference= to the VM to
> ensure the VM and its vCPUs are kept alive until the stats fds are clo= sed.=C2=A0 I'll
> send a patch.

Thanks! Another victory for hardened usercopy. :)

--
Kees Cook
--000000000000e5630306003ad243--