From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
To: Lukas Wunner <lukas@wunner.de>
Cc: David Howells <dhowells@redhat.com>, Linn Crosetto <linn@hpe.com>,
keyrings@vger.kernel.org,
Matthew Garrett <matthew.garrett@nebula.com>,
linux-security-module <linux-security-module@vger.kernel.org>,
"linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 02/16] efi: Get the secure boot status
Date: Mon, 21 Nov 2016 15:25:46 +0000 [thread overview]
Message-ID: <891BA2BC-CF94-429C-B452-162EC9A0D6B7@linaro.org> (raw)
In-Reply-To: <20161121151758.GA1319@wunner.de>
> On 21 Nov 2016, at 15:17, Lukas Wunner <lukas@wunner.de> wrote:
>
>> On Mon, Nov 21, 2016 at 01:14:52PM +0000, Ard Biesheuvel wrote:
>>> On 21 November 2016 at 12:41, David Howells <dhowells@redhat.com> wrote:
>>> Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
>>>>> Looking in efi_get_secureboot(), is there a reason:
>>>>>
>>>>> efi_guid_t var_guid = EFI_GLOBAL_VARIABLE_GUID;
>>>>>
>>>>> isn't static const?
>>>>
>>>> Not a good one, no. It used to be static const, but for some reason,
>>>> commit 30d7bf034c03 ("efi/arm64: Check SetupMode when determining
>>>> Secure Boot status") removed the static and the const (and I reviewed
>>>> it and did not complain AFAIR)
>>>> I'll gladly take a patch that reinstates that, though.
>>>
>>> Also, is there a reason that:
>>>
>>> typedef efi_status_t efi_get_variable_t (efi_char16_t *name, efi_guid_t *vendor, u32 *attr,
>>> unsigned long *data_size, void *data);
>>>
>>> Doesn't have const name and vendor?
>>
>> Yes, but not a good one either.
>>
>> Sadly, the prototypes in the UEFI spec completely ignore constness,
>> and these definitions are intended to be identical to the ones in the
>> spec. This also means, for instance, that most UEFI firmwares stores
>> these kinds of GUIDs in read-write memory, which is a potential
>> goldmine for hackers, given how GUIDs are UEFI's duct tape, i.e.,
>> keeping the world together.
>
> But the spec declares these two parameters as "IN", so it would seem
> legal to declare them const, no?
>
Good point.
> Incidentally I've already prepared commits a couple of days ago to
> change the GUID declarations to const everywhere and also change the
> get_variable prototype, I was planning to submit them for 4.11... :-)
>
I would like to take those, provided that they only modify IN pointer arguments.
next prev parent reply other threads:[~2016-11-21 15:25 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-16 21:47 [PATCH 00/16] Kernel lockdown David Howells
2016-11-16 21:47 ` [PATCH 01/16] Add the ability to lock down access to the running kernel image David Howells
[not found] ` <147933284407.19316.17886320817060158597.stgit-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-16 22:20 ` Borislav Petkov
2016-11-16 22:40 ` David Howells
2016-12-25 21:20 ` Pavel Machek
2016-12-25 21:44 ` David Howells
2016-11-16 21:47 ` [PATCH 02/16] efi: Get the secure boot status David Howells
2016-11-17 12:37 ` Lukas Wunner
2016-11-22 0:31 ` [PATCH 2/6] arm/efi: Allow invocation of arbitrary runtime services David Howells
2016-11-22 0:31 ` [PATCH 3/6] efi: Add SHIM and image security database GUID definitions David Howells
2016-11-22 0:32 ` [PATCH 4/6] efi: Get the secure boot status David Howells
2016-11-22 10:44 ` Lukas Wunner
[not found] ` <20161122104401.GC1552-JFq808J9C/izQB+pC5nmwQ@public.gmane.org>
2016-11-22 10:49 ` Ard Biesheuvel
2016-11-22 14:52 ` David Howells
[not found] ` <25371.1479826321-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-22 20:36 ` Lukas Wunner
2016-11-22 14:47 ` David Howells
2016-11-22 20:30 ` Lukas Wunner
2016-11-23 0:02 ` David Howells
[not found] ` <7199.1479826047-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-22 14:57 ` David Howells
2016-11-22 0:32 ` [PATCH 5/6] efi: Disable secure boot if shim is in insecure mode David Howells
2016-11-22 13:03 ` Lukas Wunner
2016-11-22 0:32 ` [PATCH 6/6] efi: Add EFI_SECURE_BOOT bit David Howells
2016-11-22 13:04 ` Lukas Wunner
2016-11-21 11:46 ` [PATCH 02/16] efi: Get the secure boot status David Howells
2016-11-21 19:58 ` Lukas Wunner
[not found] ` <20161117123731.GA11573-JFq808J9C/izQB+pC5nmwQ@public.gmane.org>
2016-11-21 11:42 ` David Howells
[not found] ` <29779.1479728545-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-21 11:52 ` Ard Biesheuvel
[not found] ` <CAKv+Gu-frVDhzORDRZ6XT+FxewsTgrxhXmM=DqaS6Ns4mJhQ9g-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-11-21 12:41 ` David Howells
2016-11-21 13:14 ` Ard Biesheuvel
[not found] ` <CAKv+Gu8Lhm=u97hY1y+Y+Ladk=y7pSVNrow8ML1hQUJ9+74B-w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-11-21 15:17 ` Lukas Wunner
2016-11-21 15:25 ` Ard Biesheuvel [this message]
2016-11-22 0:31 ` [PATCH 1/6] x86/efi: Allow invocation of arbitrary runtime services David Howells
[not found] ` <147977469914.6360.17194649697208113702.stgit-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-22 10:20 ` Lukas Wunner
2016-11-22 14:17 ` David Howells
2016-11-22 14:58 ` Joe Perches
[not found] ` <1479826691.1942.11.camel-6d6DIl74uiNBDgjK7y7TUQ@public.gmane.org>
2016-11-22 15:52 ` David Howells
[not found] ` <24973.1479829961-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-22 16:25 ` Joe Perches
2016-11-22 16:40 ` David Howells
2016-11-22 16:51 ` Joe Perches
2016-11-16 21:47 ` [PATCH 03/16] efi: Disable secure boot if shim is in insecure mode David Howells
2016-11-16 21:47 ` [PATCH 04/16] efi: Lock down the kernel if booted in secure boot mode David Howells
2016-11-16 21:47 ` [PATCH 05/16] efi: Add EFI_SECURE_BOOT bit David Howells
2016-11-17 21:58 ` Ard Biesheuvel
2016-11-18 11:58 ` Josh Boyer
[not found] ` <CA+5PVA6F5qEnuL2UaXS9_fJ217J93cEZDDsz9Y2BPwHXcMdX-A-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-11-18 12:10 ` Ard Biesheuvel
[not found] ` <CAKv+Gu_8r3oM-jvvuSiXTzxp0YMEVgc5KkScJ2UhGTaXm28L6w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2016-11-18 17:28 ` David Howells
2016-11-16 21:48 ` [PATCH 06/16] Add a sysrq option to exit secure boot mode David Howells
2016-11-16 21:48 ` [PATCH 07/16] kexec: Disable at runtime if the kernel is locked down David Howells
2016-11-16 21:48 ` [PATCH 08/16] Copy secure_boot flag in boot params across kexec reboot David Howells
2016-11-16 21:48 ` [PATCH 09/16] hibernate: Disable when the kernel is locked down David Howells
2016-11-16 21:48 ` [PATCH 10/16] PCI: Lock down BAR access " David Howells
[not found] ` <147933283664.19316.12454053022687659937.stgit-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-16 21:48 ` [PATCH 11/16] x86: Lock down IO port " David Howells
2016-11-16 21:49 ` [PATCH 16/16] x86: Restrict MSR " David Howells
2016-11-16 22:27 ` [PATCH 00/16] Kernel lockdown One Thousand Gnomes
2016-11-21 19:53 ` Ard Biesheuvel
2016-11-30 14:27 ` One Thousand Gnomes
2016-11-16 21:48 ` [PATCH 12/16] ACPI: Limit access to custom_method when the kernel is locked down David Howells
2016-11-16 21:48 ` [PATCH 13/16] asus-wmi: Restrict debugfs interface " David Howells
2016-11-16 21:48 ` [PATCH 14/16] Restrict /dev/mem and /dev/kmem " David Howells
2016-11-16 21:49 ` [PATCH 15/16] acpi: Ignore acpi_rsdp kernel param when the kernel has been " David Howells
2016-11-16 22:28 ` [PATCH 00/16] Kernel lockdown Justin Forbes
2016-11-21 23:10 ` [PATCH] Lock down drivers that can have io ports, io mem, irqs and dma changed David Howells
2016-11-22 6:12 ` Dominik Brodowski
2016-11-23 12:58 ` David Howells
2016-11-23 19:21 ` Dominik Brodowski
[not found] ` <20161123192143.GA482-SGhQLRGLuNwb6pqDj42GsMgv3T4z79SOrE5yTffgRl4@public.gmane.org>
2016-11-24 17:34 ` David Howells
2016-11-24 20:19 ` Dominik Brodowski
2016-11-25 14:49 ` David Howells
[not found] ` <26173.1479769852-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-28 22:32 ` Corey Minyard
2016-11-29 0:11 ` David Howells
2016-11-29 0:23 ` Corey Minyard
2016-11-29 14:03 ` David Howells
[not found] ` <6973.1480428211-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org>
2016-11-29 14:35 ` Corey Minyard
2016-11-30 14:41 ` One Thousand Gnomes
[not found] ` <20161130144105.2b6be4fe-qBU/x9rampVanCEyBjwyrvXRex20P6io@public.gmane.org>
2016-11-30 16:25 ` David Howells
2016-11-29 10:40 ` David Howells
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=891BA2BC-CF94-429C-B452-162EC9A0D6B7@linaro.org \
--to=ard.biesheuvel@linaro.org \
--cc=dhowells@redhat.com \
--cc=keyrings@vger.kernel.org \
--cc=linn@hpe.com \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=lukas@wunner.de \
--cc=matthew.garrett@nebula.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).