From: Shawn Guo <shawn.guo@linaro.org>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: Linux ARM <linux-arm-kernel@lists.infradead.org>,
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
Kernel Hardening <kernel-hardening@lists.openwall.com>,
Catalin Marinas <catalin.marinas@arm.com>,
ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
Sudeep Holla <sudeep.holla@arm.com>,
Will Deacon <will@kernel.org>,
linux-arm-msm@vger.kernel.org
Subject: Re: [PATCH v3 2/2] arm64/acpi: disallow writeable AML opregion mapping for EFI code regions
Date: Sat, 6 Feb 2021 18:45:15 +0800 [thread overview]
Message-ID: <20210206104514.GB27503@dragon> (raw)
In-Reply-To: <CAMj1kXHSkBcSDuHbsFMJjC89JrO8TxYUoabDmWerNp27s45Ngw@mail.gmail.com>
On Sat, Feb 06, 2021 at 09:10:19AM +0100, Ard Biesheuvel wrote:
> On Sat, 6 Feb 2021 at 04:11, Shawn Guo <shawn.guo@linaro.org> wrote:
> >
> > Hi Ard,
> >
> > On Fri, Jun 26, 2020 at 05:58:32PM +0200, Ard Biesheuvel wrote:
> > > Given that the contents of EFI runtime code and data regions are
> > > provided by the firmware, as well as the DSDT, it is not unimaginable
> > > that AML code exists today that accesses EFI runtime code regions using
> > > a SystemMemory OpRegion. There is nothing fundamentally wrong with that,
> > > but since we take great care to ensure that executable code is never
> > > mapped writeable and executable at the same time, we should not permit
> > > AML to create writable mapping.
> > >
> > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> >
> > I'm booting Lenovo Flex 5G laptop with ACPI, and seeing this change
> > causes a memory abort[1] when upgrading ACPI tables via initrd[2].
> > Dropping this change seems to fix the issue for me. But does that
> > looks like a correct fix to you?
> >
> > Shawn
> >
> > [1] https://fileserver.linaro.org/s/iDe9SaZeNNkyNxG
> > [2] Documentation/admin-guide/acpi/initrd_table_override.rst
> >
>
> Can you check whether reverting
>
> 32cf1a12cad43358e47dac8014379c2f33dfbed4
>
> fixes the issue too?
Yes, it does.
> If it does, please report this as a regression. The OS should not
> modify firmware provided tables in-place, regardless of how they were
> delivered.
>
> BTW I recently started using my Yoga C630 with Debian, and I am quite
> happy with it! Thanks a lot for spending the time on the installer
> etc.
Cool, glad to hear that!
Shawn
WARNING: multiple messages have this Message-ID (diff)
From: Shawn Guo <shawn.guo@linaro.org>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
Kernel Hardening <kernel-hardening@lists.openwall.com>,
Catalin Marinas <catalin.marinas@arm.com>,
linux-arm-msm@vger.kernel.org,
ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
Sudeep Holla <sudeep.holla@arm.com>,
Will Deacon <will@kernel.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v3 2/2] arm64/acpi: disallow writeable AML opregion mapping for EFI code regions
Date: Sat, 6 Feb 2021 18:45:15 +0800 [thread overview]
Message-ID: <20210206104514.GB27503@dragon> (raw)
In-Reply-To: <CAMj1kXHSkBcSDuHbsFMJjC89JrO8TxYUoabDmWerNp27s45Ngw@mail.gmail.com>
On Sat, Feb 06, 2021 at 09:10:19AM +0100, Ard Biesheuvel wrote:
> On Sat, 6 Feb 2021 at 04:11, Shawn Guo <shawn.guo@linaro.org> wrote:
> >
> > Hi Ard,
> >
> > On Fri, Jun 26, 2020 at 05:58:32PM +0200, Ard Biesheuvel wrote:
> > > Given that the contents of EFI runtime code and data regions are
> > > provided by the firmware, as well as the DSDT, it is not unimaginable
> > > that AML code exists today that accesses EFI runtime code regions using
> > > a SystemMemory OpRegion. There is nothing fundamentally wrong with that,
> > > but since we take great care to ensure that executable code is never
> > > mapped writeable and executable at the same time, we should not permit
> > > AML to create writable mapping.
> > >
> > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> >
> > I'm booting Lenovo Flex 5G laptop with ACPI, and seeing this change
> > causes a memory abort[1] when upgrading ACPI tables via initrd[2].
> > Dropping this change seems to fix the issue for me. But does that
> > looks like a correct fix to you?
> >
> > Shawn
> >
> > [1] https://fileserver.linaro.org/s/iDe9SaZeNNkyNxG
> > [2] Documentation/admin-guide/acpi/initrd_table_override.rst
> >
>
> Can you check whether reverting
>
> 32cf1a12cad43358e47dac8014379c2f33dfbed4
>
> fixes the issue too?
Yes, it does.
> If it does, please report this as a regression. The OS should not
> modify firmware provided tables in-place, regardless of how they were
> delivered.
>
> BTW I recently started using my Yoga C630 with Debian, and I am quite
> happy with it! Thanks a lot for spending the time on the installer
> etc.
Cool, glad to hear that!
Shawn
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-02-06 10:46 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-26 15:58 [PATCH v3 0/2] arm64/acpi: restrict AML opregion memory access Ard Biesheuvel
2020-06-26 15:58 ` Ard Biesheuvel
2020-06-26 15:58 ` [PATCH v3 1/2] arm64/acpi: disallow AML memory opregions to access kernel memory Ard Biesheuvel
2020-06-26 15:58 ` Ard Biesheuvel
2020-09-28 16:02 ` Jonathan Cameron
2020-09-28 16:02 ` Jonathan Cameron
2020-09-28 16:49 ` Ard Biesheuvel
2020-09-28 16:49 ` Ard Biesheuvel
2020-09-28 16:49 ` Ard Biesheuvel
2020-09-28 17:17 ` Jonathan Cameron
2020-09-28 17:17 ` Jonathan Cameron
2020-09-29 9:29 ` Ard Biesheuvel
2020-09-29 9:29 ` Ard Biesheuvel
2020-09-29 9:29 ` Ard Biesheuvel
2020-09-30 9:27 ` Jonathan Cameron
2020-09-30 9:27 ` Jonathan Cameron
2020-09-30 17:19 ` Catalin Marinas
2020-09-30 17:19 ` Catalin Marinas
2020-06-26 15:58 ` [PATCH v3 2/2] arm64/acpi: disallow writeable AML opregion mapping for EFI code regions Ard Biesheuvel
2020-06-26 15:58 ` Ard Biesheuvel
2021-02-06 3:11 ` Shawn Guo
2021-02-06 3:11 ` Shawn Guo
2021-02-06 8:10 ` Ard Biesheuvel
2021-02-06 8:10 ` Ard Biesheuvel
2021-02-06 8:10 ` Ard Biesheuvel
2021-02-06 10:17 ` Ard Biesheuvel
2021-02-06 10:17 ` Ard Biesheuvel
2021-02-06 10:17 ` Ard Biesheuvel
2021-02-06 10:45 ` Shawn Guo [this message]
2021-02-06 10:45 ` Shawn Guo
2020-07-08 16:17 ` [PATCH v3 0/2] arm64/acpi: restrict AML opregion memory access Ard Biesheuvel
2020-07-08 16:17 ` Ard Biesheuvel
2020-07-08 16:17 ` Ard Biesheuvel
2020-07-09 8:42 ` Lorenzo Pieralisi
2020-07-09 8:42 ` Lorenzo Pieralisi
2020-07-14 19:52 ` Catalin Marinas
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210206104514.GB27503@dragon \
--to=shawn.guo@linaro.org \
--cc=ardb@kernel.org \
--cc=catalin.marinas@arm.com \
--cc=kernel-hardening@lists.openwall.com \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=lorenzo.pieralisi@arm.com \
--cc=sudeep.holla@arm.com \
--cc=will@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.