Based on 1 normalized pattern(s):
this file is part of the linux kernel and is made available under
the terms of the gnu general public license version 2
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 28 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.534229504@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull EFI updates from Ingo Molnar:
"The main EFI changes in this cycle were:
- Use 32-bit alignment for efi_guid_t
- Allow the SetVirtualAddressMap() call to be omitted
- Implement earlycon=efifb based on existing earlyprintk code
- Various minor fixes and code cleanups from Sai, Ard and me"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Fix build error due to enum collision between efi.h and ima.h
efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation
x86: Make ARCH_USE_MEMREMAP_PROT a generic Kconfig symbol
efi/arm/arm64: Allow SetVirtualAddressMap() to be omitted
efi: Replace GPL license boilerplate with SPDX headers
efi/fdt: Apply more cleanups
efi: Use 32-bit alignment for efi_guid_t
efi/memattr: Don't bail on zero VA if it equals the region's PA
x86/efi: Mark can_free_region() as an __init function
This reverts commit eff8962888, which
deferred the processing of persistent memory reservations to a point
where the memory may have already been allocated and overwritten,
defeating the purpose.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190215123333.21209-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The UEFI spec revision 2.7 errata A section 8.4 has the following to
say about the virtual memory runtime services:
"This section contains function definitions for the virtual memory
support that may be optionally used by an operating system at runtime.
If an operating system chooses to make EFI runtime service calls in a
virtual addressing mode instead of the flat physical mode, then the
operating system must use the services in this section to switch the
EFI runtime services from flat physical addressing to virtual
addressing."
So it is pretty clear that calling SetVirtualAddressMap() is entirely
optional, and so there is no point in doing so unless it achieves
anything useful for us.
This is not the case for 64-bit ARM. The identity mapping used by the
firmware is arbitrarily converted into another permutation of userland
addresses (i.e., bits [63:48] cleared), and the runtime code could easily
deal with the original layout in exactly the same way as it deals with
the converted layout. However, due to constraints related to page size
differences if the OS is not running with 4k pages, and related to
systems that may expose the individual sections of PE/COFF runtime
modules as different memory regions, creating the virtual layout is a
bit fiddly, and requires us to sort the memory map and reason about
adjacent regions with identical memory types etc etc.
So the obvious fix is to stop calling SetVirtualAddressMap() altogether
on arm64 systems. However, to avoid surprises, which are notoriously
hard to diagnose when it comes to OS<->firmware interactions, let's
start by making it an opt-out feature, and implement support for the
'efi=novamap' kernel command line parameter on ARM and arm64 systems.
( Note that 32-bit ARM generally does require SetVirtualAddressMap() to be
used, given that the physical memory map and the kernel virtual address
map are not guaranteed to be non-overlapping like on arm64. However,
having support for efi=novamap,noruntime on 32-bit ARM, combined with
the recently proposed support for earlycon=efifb, is likely to be useful
to diagnose boot issues on such systems if they have no accessible serial
port. )
Tested-by: Jeffrey Hugo <jhugo@codeaurora.org>
Tested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Tested-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190202094119.13230-8-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull EFI updates from Ingo Molnar:
"The main changes in this cycle were:
- Allocate the E820 buffer before doing the
GetMemoryMap/ExitBootServices dance so we don't run out of space
- Clear EFI boot services mappings when freeing the memory
- Harden efivars against callers that invoke it on non-EFI boots
- Reduce the number of memblock reservations resulting from extensive
use of the new efi_mem_reserve_persistent() API
- Other assorted fixes and cleanups"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Don't unmap EFI boot services code/data regions for EFI_OLD_MEMMAP and EFI_MIXED_MODE
efi: Reduce the amount of memblock reservations for persistent allocations
efi: Permit multiple entries in persistent memreserve data structure
efi/libstub: Disable some warnings for x86{,_64}
x86/efi: Move efi_<reserve/free>_boot_services() to arch/x86
x86/efi: Unmap EFI boot services code/data regions from efi_pgd
x86/mm/pageattr: Introduce helper function to unmap EFI boot services
efi/fdt: Simplify the get_fdt() flow
efi/fdt: Indentation fix
firmware/efi: Add NULL pointer checks in efivars API functions
We wish to introduce a 52-bit virtual address space for userspace but
maintain compatibility with software that assumes the maximum VA space
size is 48 bit.
In order to achieve this, on 52-bit VA systems, we make mmap behave as
if it were running on a 48-bit VA system (unless userspace explicitly
requests a VA where addr[51:48] != 0).
On a system running a 52-bit userspace we need TASK_SIZE to represent
the 52-bit limit as it is used in various places to distinguish between
kernelspace and userspace addresses.
Thus we need a new limit for mmap, stack, ELF loader and EFI (which uses
TTBR0) to represent the non-extended VA space.
This patch introduces DEFAULT_MAP_WINDOW and DEFAULT_MAP_WINDOW_64 and
switches the appropriate logic to use that instead of TASK_SIZE.
Signed-off-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
In preparation of updating efi_mem_reserve_persistent() to cause less
fragmentation when dealing with many persistent reservations, update
the struct definition and the code that handles it currently so it
can describe an arbitrary number of reservations using a single linked
list entry. The actual optimization will be implemented in a subsequent
patch.
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arend van Spriel <arend.vanspriel@broadcom.com>
Cc: Bhupesh Sharma <bhsharma@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Snowberg <eric.snowberg@oracle.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Jon Hunter <jonathanh@nvidia.com>
Cc: Julien Thierry <julien.thierry@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: YiFei Zhu <zhuyifei1999@gmail.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181129171230.18699-10-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The new memory EFI reservation feature we introduced to allow memory
reservations to persist across kexec may trigger an unbounded number
of calls to memblock_reserve(). The memblock subsystem can deal with
this fine, but not before memblock resizing is enabled, which we can
only do after paging_init(), when the memory we reallocate the array
into is actually mapped.
So break out the memreserve table processing into a separate routine
and call it after paging_init() on arm64. On ARM, because of limited
reviewing bandwidth of the maintainer, we cannot currently fix this,
so instead, disable the EFI persistent memreserve entirely on ARM so
we can fix it later.
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20181114175544.12860-5-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Installing UEFI configuration tables can only be done before calling
ExitBootServices(), so if we want to use the new MEMRESRVE config table
from the kernel proper, we need to install a dummy entry from the stub.
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
There's one ARM, one x86_32 and one x86_64 version of efi_open_volume()
which can be folded into a single shared version by masking their
differences with the efi_call_proto() macro introduced by commit:
3552fdf29f ("efi: Allow bitness-agnostic protocol calls").
To be able to dereference the device_handle attribute from the
efi_loaded_image_t table in an arch- and bitness-agnostic manner,
introduce the efi_table_attr() macro (which already exists for x86)
to arm and arm64.
No functional change intended.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180720014726.24031-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There are various ways a platform can provide a device tree binary
to the kernel, with different levels of sophistication:
- ideally, the UEFI firmware, which is tightly coupled with the
platform, provides a device tree image directly as a UEFI
configuration table, and typically permits the contents to be
manipulated either via menu options or via UEFI environment
variables that specify a replacement image,
- GRUB for ARM has a 'devicetree' directive which allows a device
tree image to be loaded from any location accessible to GRUB, and
supersede the one provided by the firmware,
- the EFI stub implements a dtb= command line option that allows a
device tree image to be loaded from a file residing in the same
file system as the one the kernel image was loaded from.
The dtb= command line option was never intended to be more than a
development feature, to allow the other options to be implemented
in parallel. So let's make it an opt-in feature that is disabled
by default, but can be re-enabled at will.
Note that we already disable the dtb= command line option when we
detect that we are running with UEFI Secure Boot enabled.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Alexander Graf <agraf@suse.de>
Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180711094040.12506-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull ARM fixes from Russell King:
- omit EFI memory map sorting, which was recently introduced, but
caused problems with the decompressor due to additional sections
being emitted.
- avoid unaligned load fault-generating instructions in the
decompressor by switching to a private unaligned implementation.
- add a symbol into the decompressor to further debug non-boot
situations (ld's documentation is extremely poor for how "." works,
ld doesn't seem to follow its own documentation!)
- parse endian information to sparse
* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: add debug ".edata_real" symbol
ARM: 8716/1: pass endianness info to sparse
efi/libstub: arm: omit sorting of the UEFI memory map
ARM: 8715/1: add a private asm/unaligned.h
ARM shares its EFI stub implementation with arm64, which has some
special handling in the virtual remapping code to
a) make sure that we can map everything even if the OS executes
with 64k page size, and
b) make sure that adjacent regions with the same attributes are not
reordered or moved apart in memory.
The latter is a workaround for a 'feature' that was shortly recommended
by UEFI spec v2.5, but deprecated shortly after, due to the fact that
it broke many OS installers, including non-Linux ones, and it was never
widely implemented for ARM systems. Before implementing b), the arm64
code simply rounded up all regions to 64 KB granularity, but given that
that results in moving adjacent regions apart, it had to be refined when
b) was implemented.
The adjacency check requires a sort() pass, due to the fact that the
UEFI spec does not mandate any ordering, and the inclusion of the
lib/sort.c code into the ARM EFI stub is causing some trouble with
the decompressor build due to the fact that its EXPORT_SYMBOL() call
triggers the creation of ksymtab/kcrctab sections.
So let's simply do away with the adjacency check for ARM, and simply put
all UEFI runtime regions together if they have the same memory attributes.
This is guaranteed to work, given that ARM only supports 4 KB pages,
and allows us to remove the sort() call entirely.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Commit:
e69176d68d ("ef/libstub/arm/arm64: Randomize the base of the UEFI rt services region")
implemented randomization of the virtual mapping that the OS chooses for
the UEFI runtime services. This was motivated by the fact that UEFI usually
does not bother to specify any permission restrictions for those regions,
making them prime real estate for exploitation now that the OS is getting
more and more careful not to leave any R+W+X mapped regions lying around.
However, this randomization breaks assumptions in the resume from
hibernation code, which expects all memory regions populated by UEFI to
remain in the same place, including their virtual mapping into the OS
memory space. While this assumption may not be entirely reasonable in the
first place, breaking it deliberately does not make a lot of sense either.
So let's refrain from this randomization pass if CONFIG_HIBERNATION=y.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: James Morse <james.morse@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20171025100448.26056-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If a machine is reset while secrets are present in RAM, it may be
possible for code executed after the reboot to extract those secrets
from untouched memory. The Trusted Computing Group specified a mechanism
for requesting that the firmware clear all RAM on reset before booting
another OS. This is done by setting the MemoryOverwriteRequestControl
variable at startup. If userspace can ensure that all secrets are
removed as part of a controlled shutdown, it can reset this variable to
0 before triggering a hardware reboot.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As reported by James, Catalin and Mark, commit:
e69176d68d ("ef/libstub/arm/arm64: Randomize the base of the UEFI rt services region")
... results in a crash in the firmware, regardless of whether KASLR
is in effect or not and whether the firmware implements EFI_RNG_PROTOCOL
or not.
Mark has identified the root cause to be the inappropriate use of
TASK_SIZE in the stub, which arm64 defines as:
#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
TASK_SIZE_32 : TASK_SIZE_64)
and testing thread flags at this point results in the dereference of
pointers in uninitialized structures.
So instead, introduce a preprocessor symbol EFI_RT_VIRTUAL_LIMIT and
define it to TASK_SIZE_64 on arm64 and TASK_SIZE on ARM, both of which
are compile time constants. Also, change the 'headroom' variable to
static const to force an error if this might change in the future.
Tested-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170417093201.10181-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Update the allocation logic for the virtual mapping of the UEFI runtime
services to start from a randomized base address if KASLR is in effect,
and if the UEFI firmware exposes an implementation of EFI_RNG_PROTOCOL.
This makes it more difficult to predict the location of exploitable
data structures in the runtime UEFI firmware, which increases robustness
against attacks. Note that these regions are only mapped during the
time a runtime service call is in progress, and only on a single CPU
at a time, bit given the lack of a downside, let's enable it nonetheless.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bhe@redhat.com
Cc: bhsharma@redhat.com
Cc: eugene@hp.com
Cc: evgeny.kalugin@intel.com
Cc: jhugo@codeaurora.org
Cc: leif.lindholm@linaro.org
Cc: linux-efi@vger.kernel.org
Cc: mark.rutland@arm.com
Cc: roy.franz@cavium.com
Cc: rruigrok@codeaurora.org
Link: http://lkml.kernel.org/r/20170404160910.28115-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The EFI stub currently prints a number of diagnostic messages that do
not carry a lot of information. Since these prints are not controlled
by 'loglevel' or other command line parameters, and since they appear on
the EFI framebuffer as well (if enabled), it would be nice if we could
turn them off.
So let's add support for the 'quiet' command line parameter in the stub,
and disable the non-error prints if it is passed.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bhe@redhat.com
Cc: bhsharma@redhat.com
Cc: bp@alien8.de
Cc: eugene@hp.com
Cc: evgeny.kalugin@intel.com
Cc: jhugo@codeaurora.org
Cc: leif.lindholm@linaro.org
Cc: linux-efi@vger.kernel.org
Cc: roy.franz@cavium.com
Cc: rruigrok@codeaurora.org
Link: http://lkml.kernel.org/r/20170404160910.28115-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On arm64, we have made some changes over the past year to the way the
kernel itself is allocated and to how it deals with the initrd and FDT.
This patch brings the allocation logic in the EFI stub in line with that,
which is necessary because the introduction of KASLR has created the
possibility for the initrd to be allocated in a place where the kernel
may not be able to map it. (This is mostly a theoretical scenario, since
it only affects systems where the physical memory footprint exceeds the
size of the linear mapping.)
Since we know the kernel itself will be covered by the linear mapping,
choose a suitably sized window (i.e., based on the size of the linear
region) covering the kernel when allocating memory for the initrd.
The FDT may be anywhere in memory on arm64 now that we map it via the
fixmap, so we can lift the address restriction there completely.
Tested-by: Richard Ruigrok <rruigrok@codeaurora.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170404160245.27812-4-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Get the firmware's secure-boot status in the kernel boot wrapper and stash
it somewhere that the main kernel image can find.
The efi_get_secureboot() function is extracted from the ARM stub and (a)
generalised so that it can be called from x86 and (b) made to use
efi_call_runtime() so that it can be run in mixed-mode.
For x86, it is stored in boot_params and can be overridden by the boot
loader or kexec. This allows secure-boot mode to be passed on to a new
kernel.
Suggested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1486380166-31868-5-git-send-email-ard.biesheuvel@linaro.org
[ Small readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There's one ARM, one x86_32 and one x86_64 version which can be folded
into a single shared version by masking their differences with the shiny
new efi_call_proto() macro.
No functional change intended.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1485868902-20401-2-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
install the Linux-specific RNG seed UEFI config table. This will be
picked up by the EFI routines in the core kernel to seed the kernel
entropy pool.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-6-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This adds the code to the ARM and arm64 versions of the UEFI stub to
populate struct screen_info based on the information received from the
firmware via the GOP protocol.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-23-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
According to the UEFI specification (version 2.5 Errata A, page 87):
The platform firmware is operating in secure boot mode if the value of
the SetupMode variable is 0 and the SecureBoot variable is set to 1. A
platform cannot operate in secure boot mode if the SetupMode variable
is set to 1.
Check the value of the SetupMode variable when determining the state of
Secure Boot.
Plus also do minor cleanup, change sizeof() use to match kernel style guidelines.
Signed-off-by: Linn Crosetto <linn@hpe.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roy Franz <roy.franz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-6-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Certain code in the boot path may require the ability to determine whether
UEFI Secure Boot is definitely enabled, for example printing status to the
console. Other code may need to know when UEFI Secure Boot is definitely
disabled, for example restricting use of kernel parameters.
If an unexpected error is returned from GetVariable() when querying the
status of UEFI Secure Boot, return an error to the caller. This allows the
caller to determine the definite state, and to take appropriate action if
an expected error is returned.
Signed-off-by: Linn Crosetto <linn@hpe.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roy Franz <roy.franz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1461614832-17633-5-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull EFI updates from Ingo Molnar:
"The main changes are:
- Use separate EFI page tables when executing EFI firmware code.
This isolates the EFI context from the rest of the kernel, which
has security and general robustness advantages. (Matt Fleming)
- Run regular UEFI firmware with interrupts enabled. This is already
the status quo under other OSs. (Ard Biesheuvel)
- Various x86 EFI enhancements, such as the use of non-executable
attributes for EFI memory mappings. (Sai Praneeth Prakhya)
- Various arm64 UEFI enhancements. (Ard Biesheuvel)
- ... various fixes and cleanups.
The separate EFI page tables feature got delayed twice already,
because it's an intrusive change and we didn't feel confident about
it - third time's the charm we hope!"
* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
x86/mm/pat: Fix boot crash when 1GB pages are not supported by the CPU
x86/efi: Only map kernel text for EFI mixed mode
x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables
x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()
efi/arm*: Perform hardware compatibility check
efi/arm64: Check for h/w support before booting a >4 KB granular kernel
efi/arm: Check for LPAE support before booting a LPAE kernel
efi/arm-init: Use read-only early mappings
efi/efistub: Prevent __init annotations from being used
arm64/vmlinux.lds.S: Handle .init.rodata.xxx and .init.bss sections
efi/arm64: Drop __init annotation from handle_kernel_image()
x86/mm/pat: Use _PAGE_GLOBAL bit for EFI page table mappings
efi/runtime-wrappers: Run UEFI Runtime Services with interrupts enabled
efi: Reformat GUID tables to follow the format in UEFI spec
efi: Add Persistent Memory type name
efi: Add NV memory attribute
x86/efi: Show actual ending addresses in efi_print_memmap
x86/efi/bgrt: Don't ignore the BGRT if the 'valid' bit is 0
efivars: Use to_efivar_entry
efi: Runtime-wrapper: Get rid of the rtc_lock spinlock
...
Since arm64 does not use a decompressor that supplies an execution
environment where it is feasible to some extent to provide a source of
randomness, the arm64 KASLR kernel depends on the bootloader to supply
some random bits in the /chosen/kaslr-seed DT property upon kernel entry.
On UEFI systems, we can use the EFI_RNG_PROTOCOL, if supplied, to obtain
some random bits. At the same time, use it to randomize the offset of the
kernel Image in physical memory.
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Before proceeding with relocating the kernel and parsing the command line,
insert a call to check_platform_features() to allow an arch specific check
to be performed whether the current kernel can execute on the current
hardware.
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1455712566-16727-11-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch adds EFI stub support for the ARM Linux kernel.
The EFI stub operates similarly to the x86 and arm64 stubs: it is a
shim between the EFI firmware and the normal zImage entry point, and
sets up the environment that the zImage is expecting. This includes
optionally loading the initrd and device tree from the system partition
based on the kernel command line.
Signed-off-by: Roy Franz <roy.franz@linaro.org>
Tested-by: Ryan Harkin <ryan.harkin@linaro.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
The new Properties Table feature introduced in UEFIv2.5 may
split memory regions that cover PE/COFF memory images into
separate code and data regions. Since these regions only differ
in the type (runtime code vs runtime data) and the permission
bits, but not in the memory type attributes (UC/WC/WT/WB), the
spec does not require them to be aligned to 64 KB.
Since the relative offset of PE/COFF .text and .data segments
cannot be changed on the fly, this means that we can no longer
pad out those regions to be mappable using 64 KB pages.
Unfortunately, there is no annotation in the UEFI memory map
that identifies data regions that were split off from a code
region, so we must apply this logic to all adjacent runtime
regions whose attributes only differ in the permission bits.
So instead of rounding each memory region to 64 KB alignment at
both ends, only round down regions that are not directly
preceded by another runtime region with the same type
attributes. Since the UEFI spec does not mandate that the memory
map be sorted, this means we also need to sort it first.
Note that this change will result in all EFI_MEMORY_RUNTIME
regions whose start addresses are not aligned to the OS page
size to be mapped with executable permissions (i.e., on kernels
compiled with 64 KB pages). However, since these mappings are
only active during the time that UEFI Runtime Services are being
invoked, the window for abuse is rather small.
Tested-by: Mark Salter <msalter@redhat.com>
Tested-by: Mark Rutland <mark.rutland@arm.com> [UEFI 2.4 only]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Reviewed-by: Mark Salter <msalter@redhat.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org> # v4.0+
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1443218539-7610-3-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When allocating memory for the copy of the FDT that the stub
modifies and passes to the kernel, it uses the current size as
an estimate of how much memory to allocate, and increases it page
by page if it turns out to be too small. However, when loading
the FDT from a UEFI configuration table, the estimated size is
left at its default value of zero, and the allocation loop runs
starting from zero all the way up to the allocation size that
finally fits the updated FDT.
Instead, retrieve the size of the FDT from the FDT header when
loading it from the UEFI config table.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Roy Franz <roy.franz@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
- reimplementation of the virtual remapping of UEFI Runtime Services in
a way that is stable across kexec
- emulation of the "setend" instruction for 32-bit tasks (user
endianness switching trapped in the kernel, SCTLR_EL1.E0E bit set
accordingly)
- compat_sys_call_table implemented in C (from asm) and made it a
constant array together with sys_call_table
- export CPU cache information via /sys (like other architectures)
- DMA API implementation clean-up in preparation for IOMMU support
- macros clean-up for KVM
- dropped some unnecessary cache+tlb maintenance
- CONFIG_ARM64_CPU_SUSPEND clean-up
- defconfig update (CPU_IDLE)
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
"arm64 updates for 3.20:
- reimplementation of the virtual remapping of UEFI Runtime Services
in a way that is stable across kexec
- emulation of the "setend" instruction for 32-bit tasks (user
endianness switching trapped in the kernel, SCTLR_EL1.E0E bit set
accordingly)
- compat_sys_call_table implemented in C (from asm) and made it a
constant array together with sys_call_table
- export CPU cache information via /sys (like other architectures)
- DMA API implementation clean-up in preparation for IOMMU support
- macros clean-up for KVM
- dropped some unnecessary cache+tlb maintenance
- CONFIG_ARM64_CPU_SUSPEND clean-up
- defconfig update (CPU_IDLE)
The EFI changes going via the arm64 tree have been acked by Matt
Fleming. There is also a patch adding sys_*stat64 prototypes to
include/linux/syscalls.h, acked by Andrew Morton"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (47 commits)
arm64: compat: Remove incorrect comment in compat_siginfo
arm64: Fix section mismatch on alloc_init_p[mu]d()
arm64: Avoid breakage caused by .altmacro in fpsimd save/restore macros
arm64: mm: use *_sect to check for section maps
arm64: drop unnecessary cache+tlb maintenance
arm64:mm: free the useless initial page table
arm64: Enable CPU_IDLE in defconfig
arm64: kernel: remove ARM64_CPU_SUSPEND config option
arm64: make sys_call_table const
arm64: Remove asm/syscalls.h
arm64: Implement the compat_sys_call_table in C
syscalls: Declare sys_*stat64 prototypes if __ARCH_WANT_(COMPAT_)STAT64
compat: Declare compat_sys_sigpending and compat_sys_sigprocmask prototypes
arm64: uapi: expose our struct ucontext to the uapi headers
smp, ARM64: Kill SMP single function call interrupt
arm64: Emulate SETEND for AArch32 tasks
arm64: Consolidate hotplug notifier for instruction emulation
arm64: Track system support for mixed endian EL0
arm64: implement generic IOMMU configuration
arm64: Combine coherent and non-coherent swiotlb dma_ops
...
since that's a more logical and accurate place - Leif Lindholm
* Update efibootmgr URL in Kconfig help - Peter Jones
* Improve accuracy of EFI guid function names - Borislav Petkov
* Expose firmware platform size in sysfs for the benefit of EFI boot
loader installers and other utilities - Steve McIntyre
* Cleanup __init annotations for arm64/efi code - Ard Biesheuvel
* Mark the UIE as unsupported for rtc-efi - Ard Biesheuvel
* Fix memory leak in error code path of runtime map code - Dan Carpenter
* Improve robustness of get_memory_map() by removing assumptions on the
size of efi_memory_desc_t (which could change in future spec
versions) and querying the firmware instead of guessing about the
memmap size - Ard Biesheuvel
* Remove superfluous guid unparse calls - Ivan Khoronzhuk
* Delete unnecessary chosen@0 DT node FDT code since was duplicated
from code in drivers/of and is entirely unnecessary - Leif Lindholm
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/efi
Pull EFI updates from Matt Fleming:
" - Move efivarfs from the misc filesystem section to pseudo filesystem,
since that's a more logical and accurate place - Leif Lindholm
- Update efibootmgr URL in Kconfig help - Peter Jones
- Improve accuracy of EFI guid function names - Borislav Petkov
- Expose firmware platform size in sysfs for the benefit of EFI boot
loader installers and other utilities - Steve McIntyre
- Cleanup __init annotations for arm64/efi code - Ard Biesheuvel
- Mark the UIE as unsupported for rtc-efi - Ard Biesheuvel
- Fix memory leak in error code path of runtime map code - Dan Carpenter
- Improve robustness of get_memory_map() by removing assumptions on the
size of efi_memory_desc_t (which could change in future spec
versions) and querying the firmware instead of guessing about the
memmap size - Ard Biesheuvel
- Remove superfluous guid unparse calls - Ivan Khoronzhuk
- Delete unnecessary chosen@0 DT node FDT code since was duplicated
from code in drivers/of and is entirely unnecessary - Leif Lindholm
There's nothing super scary, mainly cleanups, and a merge from Ricardo who
kindly picked up some patches from the linux-efi mailing list while I
was out on annual leave in December.
Perhaps the biggest risk is the get_memory_map() change from Ard, which
changes the way that both the arm64 and x86 EFI boot stub build the
early memory map. It would be good to have it bake in linux-next for a
while.
"
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This ensures all stub component are freed when the kernel proper is
done booting, by prefixing the names of all ELF sections that have
the SHF_ALLOC attribute with ".init". This approach ensures that even
implicitly emitted allocated data (like initializer values and string
literals) are covered.
At the same time, remove some __init annotations in the stub that have
now become redundant, and add the __init annotation to handle_kernel_image
which will now trigger a section mismatch warning without it.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
In order to support kexec, the kernel needs to be able to deal with the
state of the UEFI firmware after SetVirtualAddressMap() has been called.
To avoid having separate code paths for non-kexec and kexec, let's move
the call to SetVirtualAddressMap() to the stub: this will guarantee us
that it will only be called once (since the stub is not executed during
kexec), and ensures that the UEFI state is identical between kexec and
normal boot.
This implies that the layout of the virtual mapping needs to be created
by the stub as well. All regions are rounded up to a naturally aligned
multiple of 64 KB (for compatibility with 64k pages kernels) and recorded
in the UEFI memory map. The kernel proper reads those values and installs
the mappings in a dedicated set of page tables that are swapped in during
UEFI Runtime Services calls.
Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
In the absence of a DTB configuration table, the EFI stub will happily
continue attempting to boot a kernel, despite the fact that this kernel
may not function without a description of the hardware. In this case, as
with a typo'd "dtb=" option (e.g. "dbt=") or many other possible
failures, the only output seen by the user will be the rather terse
output from the EFI stub:
EFI stub: Booting Linux Kernel...
To aid those attempting to debug such failures, this patch adds a notice
when no DTB is found, making the output more helpful:
EFI stub: Booting Linux Kernel...
EFI stub: Generating empty DTB
Additionally, a positive acknowledgement is added when a user-specified
DTB is in use:
EFI stub: Booting Linux Kernel...
EFI stub: Using DTB from command line
Similarly, a positive acknowledgement is added when a DTB from a
configuration table is in use:
EFI stub: Booting Linux Kernel...
EFI stub: Using DTB from configuration table
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Roy Franz <roy.franz@linaro.org>
Acked-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
We need a way to customize the behaviour of the EFI boot stub, in
particular, we need a way to disable the "chunking" workaround, used
when reading files from the EFI System Partition.
One of my machines doesn't cope well when reading files in 1MB chunks to
a buffer above the 4GB mark - it appears that the "chunking" bug
workaround triggers another firmware bug. This was only discovered with
commit 4bf7111f50 ("x86/efi: Support initrd loaded above 4G"), and
that commit is perfectly valid. The symptom I observed was a corrupt
initrd rather than any kind of crash.
efi= is now used to specify EFI parameters in two very different
execution environments, the EFI boot stub and during kernel boot.
There is also a slight performance optimization by enabling efi=nochunk,
but that's offset by the fact that you're more likely to run into
firmware issues, at least on x86. This is the rationale behind leaving
the workaround enabled by default.
Also provide some documentation for EFI_READ_CHUNK_SIZE and why we're
using the current value of 1MB.
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Roy Franz <roy.franz@linaro.org>
Cc: Maarten Lankhorst <m.b.lankhorst@gmail.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
This patch changes both x86 and arm64 efistub implementations
from #including shared .c files under drivers/firmware/efi to
building shared code as a static library.
The x86 code uses a stub built into the boot executable which
uncompresses the kernel at boot time. In this case, the library is
linked into the decompressor.
In the arm64 case, the stub is part of the kernel proper so the library
is linked into the kernel proper as well.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Thomas Gleixner