linux-toradex.git/drivers/firmware/efi/efi.c, branch v5.10-rc2

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: 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: add missed destroy_workqueue when efisubsys_init fails

2020-08-20T09:18:45+00:00

destroy_workqueue() should be called to destroy efi_rts_wq
when efisubsys_init() init resources fails.

Cc: 
Reported-by: Hulk Robot 
Signed-off-by: Li Heng 
Link: https://lore.kernel.org/r/1595229738-10087-1-git-send-email-liheng40@huawei.com
Signed-off-by: Ard Biesheuvel

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

efi: Make it possible to disable efivar_ssdt entirely

2020-06-16T09:01:07+00:00

In most cases, such as CONFIG_ACPI_CUSTOM_DSDT and
CONFIG_ACPI_TABLE_UPGRADE, boot-time modifications to firmware tables
are tied to specific Kconfig options.  Currently this is not the case
for modifying the ACPI SSDT via the efivar_ssdt kernel command line
option and associated EFI variable.

This patch adds CONFIG_EFI_CUSTOM_SSDT_OVERLAYS, which defaults
disabled, in order to allow enabling or disabling that feature during
the build.

Cc: 
Signed-off-by: Peter Jones 
Link: https://lore.kernel.org/r/20200615202408.2242614-1-pjones@redhat.com
Signed-off-by: Ard Biesheuvel

efi: Replace zero-length array and use struct_size() helper

2020-06-15T12:38:56+00:00

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

Lastly, make use of the sizeof_field() helper instead of an open-coded
version.

This issue was found with the help of Coccinelle and audited _manually_.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva 
Reviewed-by: Kees Cook 
Link: https://lore.kernel.org/r/20200527171425.GA4053@embeddedor
Signed-off-by: Ard Biesheuvel

mmap locking API: add MMAP_LOCK_INITIALIZER

2020-06-09T16:39:14+00:00

Define a new initializer for the mmap locking api.  Initially this just
evaluates to __RWSEM_INITIALIZER as the API is defined as wrappers around
rwsem.

Signed-off-by: Michel Lespinasse 
Signed-off-by: Andrew Morton 
Reviewed-by: Laurent Dufour 
Reviewed-by: Vlastimil Babka 
Reviewed-by: Daniel Jordan 
Cc: Davidlohr Bueso 
Cc: David Rientjes 
Cc: Hugh Dickins 
Cc: Jason Gunthorpe 
Cc: Jerome Glisse 
Cc: John Hubbard 
Cc: Liam Howlett 
Cc: Matthew Wilcox 
Cc: Peter Zijlstra 
Cc: Ying Han 
Link: http://lkml.kernel.org/r/20200520052908.204642-9-walken@google.com
Signed-off-by: Linus Torvalds

Merge tag 'v5.7-rc7' into efi/core, to refresh the branch and pick up fixes

2020-05-25T13:10:37+00:00

Signed-off-by: Ingo Molnar

efi: Pull up arch-specific prototype efi_systab_show_arch()

2020-05-17T09:46:50+00:00

Pull up arch-specific prototype efi_systab_show_arch() in order to
fix a -Wmissing-prototypes warning:

arch/x86/platform/efi/efi.c:957:7: warning: no previous prototype for
‘efi_systab_show_arch’ [-Wmissing-prototypes]
char *efi_systab_show_arch(char *str)

Signed-off-by: Benjamin Thiel 
Link: https://lore.kernel.org/r/20200516132647.14568-1-b.thiel@posteo.de
Signed-off-by: Ard Biesheuvel