linux.git/include/linux/efi.h, branch v5.11-rc2

efi: ia64: disable the capsule loader

2020-12-14T15:24:19+00:00

EFI capsule loading is a feature that was introduced into EFI long after
its initial introduction on Itanium, and it is highly unlikely that IA64
systems are receiving firmware updates in the first place, let alone
using EFI capsules.

So let's disable capsule support altogether on IA64. This fixes a build
error on IA64 due to a recent change that added an unconditional
include of asm/efi.h, which IA64 does not provide.

While at it, tweak the make rules a bit so that the EFI capsule
component that is always builtin (even if the EFI capsule loader itself
is built as a module) is omitted for all architectures if the module is
not enabled in the build.

Cc: Tony Luck 
Link: https://lore.kernel.org/linux-efi/20201214152200.38353-1-ardb@kernel.org
Signed-off-by: Ard Biesheuvel

efi: generalize efi_get_secureboot

2020-11-04T22:05:40+00:00

Generalize the efi_get_secureboot() function so not only efistub but also
other subsystems can use it.

Note that the MokSbState handling is not factored out: the variable is
boot time only, and so it cannot be parameterized as easily. Also, the
IMA code will switch to this version in a future patch, and it does not
incorporate the MokSbState exception in the first place.

Note that the new efi_get_secureboot_mode() helper treats any failures
to read SetupMode as setup mode being disabled.

Co-developed-by: Chester Lin 
Signed-off-by: Chester Lin 
Acked-by: Mimi Zohar 
Signed-off-by: Ard Biesheuvel

Merge branch 'efi/urgent' into efi/core, to pick up fixes

2020-10-12T11:38:31+00:00

These fixes missed the v5.9 merge window, pick them up for early v5.10 merge.

Signed-off-by: Ingo Molnar

efi: efivars: un-export efivars_sysfs_init()

2020-09-29T17:40:57+00:00

efivars_sysfs_init() is only used locally in the source file that
defines it, so make it static and unexport it.

Signed-off-by: Ard Biesheuvel

efi: pstore: move workqueue handling out of efivars

2020-09-29T17:40:57+00:00

The worker thread that gets kicked off to sync the state of the
EFI variable list is only used by the EFI pstore implementation,
and is defined in its source file. So let's move its scheduling
there as well. Since our efivar_init() scan will bail on duplicate
entries, there is no need to disable the workqueue like we did
before, so we can run it unconditionally.

Signed-off-by: Ard Biesheuvel

efi: pstore: disentangle from deprecated efivars module

2020-09-29T17:40:57+00:00

The EFI pstore implementation relies on the 'efivars' abstraction,
which encapsulates the EFI variable store in a way that can be
overridden by other backing stores, like the Google SMI one.

On top of that, the EFI pstore implementation also relies on the
efivars.ko module, which is a separate layer built on top of the
'efivars' abstraction that exposes the [deprecated] sysfs entries
for each variable that exists in the backing store.

Since the efivars.ko module is deprecated, and all users appear to
have moved to the efivarfs file system instead, let's prepare for
its removal, by removing EFI pstore's dependency on it.

Signed-off-by: Ard Biesheuvel

efi: Add definition of EFI_MEMORY_CPU_CRYPTO and ability to report it

2020-09-25T21:29:04+00:00

Incorporate the definition of EFI_MEMORY_CPU_CRYPTO from the UEFI
specification v2.8, and wire it into our memory map dumping routine
as well.

To make a bit of space in the output buffer, which is provided by
the various callers, shorten the descriptive names of the memory
types.

Reviewed-by: Laszlo Ersek 
Signed-off-by: Ard Biesheuvel

efi: Support for MOK variable config table

2020-09-16T15:53:42+00:00

Because of system-specific EFI firmware limitations, EFI volatile
variables may not be capable of holding the required contents of
the Machine Owner Key (MOK) certificate store when the certificate
list grows above some size. Therefore, an EFI boot loader may pass
the MOK certs via a EFI configuration table created specifically for
this purpose to avoid this firmware limitation.

An EFI configuration table is a much more primitive mechanism
compared to EFI variables and is well suited for one-way passage
of static information from a pre-OS environment to the kernel.

This patch adds initial kernel support to recognize, parse,
and validate the EFI MOK configuration table, where named
entries contain the same data that would otherwise be provided
in similarly named EFI variables.

Additionally, this patch creates a sysfs binary file for each
EFI MOK configuration table entry found. These files are read-only
to root and are provided for use by user space utilities such as
mokutil.

A subsequent patch will load MOK certs into the trusted platform
key ring using this infrastructure.

Signed-off-by: Lenny Szubowicz 
Link: https://lore.kernel.org/r/20200905013107.10457-2-lszubowi@redhat.com
Signed-off-by: Ard Biesheuvel

efi: provide empty efi_enter_virtual_mode implementation

2020-08-07T18:33:28+00:00

When CONFIG_EFI is not enabled, we might get an undefined reference to
efi_enter_virtual_mode() error, if this efi_enabled() call isn't inlined
into start_kernel().  This happens in particular, if start_kernel() is
annodated with __no_sanitize_address.

Reported-by: kernel test robot 
Signed-off-by: Andrey Konovalov 
Signed-off-by: Andrew Morton 
Acked-by: Ard Biesheuvel 
Cc: Alexander Potapenko 
Cc: Andrey Ryabinin 
Cc: Catalin Marinas 
Cc: Dmitry Vyukov 
Cc: Elena Petrova 
Cc: Marco Elver 
Cc: Vincenzo Frascino 
Cc: Walter Wu 
Link: http://lkml.kernel.org/r/6514652d3a32d3ed33d6eb5c91d0af63bf0d1a0c.1596544734.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds

efi/efivars: Expose RT service availability via efivars abstraction

2020-07-09T07:14:29+00:00

Commit

  bf67fad19e493b ("efi: Use more granular check for availability for variable services")

introduced a check into the efivarfs, efi-pstore and other drivers that
aborts loading of the module if not all three variable runtime services
(GetVariable, SetVariable and GetNextVariable) are supported. However, this
results in efivarfs being unavailable entirely if only SetVariable support
is missing, which is only needed if you want to make any modifications.
Also, efi-pstore and the sysfs EFI variable interface could be backed by
another implementation of the 'efivars' abstraction, in which case it is
completely irrelevant which services are supported by the EFI firmware.

So make the generic 'efivars' abstraction dependent on the availibility of
the GetVariable and GetNextVariable EFI runtime services, and add a helper
'efivar_supports_writes()' to find out whether the currently active efivars
abstraction supports writes (and wire it up to the availability of
SetVariable for the generic one).

Then, use the efivar_supports_writes() helper to decide whether to permit
efivarfs to be mounted read-write, and whether to enable efi-pstore or the
sysfs EFI variable interface altogether.

Fixes: bf67fad19e493b ("efi: Use more granular check for availability for variable services")
Reported-by: Heinrich Schuchardt 
Acked-by: Ilias Apalodimas 
Tested-by: Ilias Apalodimas 
Signed-off-by: Ard Biesheuvel