efi/libstub: Clean up command line parsing routine

We currently parse the command non-destructively, to avoid having to
allocate memory for a copy before passing it to the standard parsing
routines

efi/libstub: Clean up command line parsing routine

We currently parse the command non-destructively, to avoid having to
allocate memory for a copy before passing it to the standard parsing
routines that are used by the core kernel, and which modify the input
to delineate the parsed tokens with NUL characters.

Instead, we call strstr() and strncmp() to go over the input multiple
times, and match prefixes rather than tokens, which implies that we
would match, e.g., 'nokaslrfoo' in the stub and disable KASLR, while
the kernel would disregard the option and run with KASLR enabled.

In order to avoid having to reason about whether and how this behavior
may be abused, let's clean up the parsing routines, and rebuild them
on top of the existing helpers.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

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efi/libstub: Move file I/O support code into separate file

Split off the file I/O support code into a separate source file so
it ends up in a separate object file in the static library, allowing
the

efi/libstub: Move file I/O support code into separate file

Split off the file I/O support code into a separate source file so
it ends up in a separate object file in the static library, allowing
the linker to omit it if the routines are not used.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

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efi/libstub: Move efi_random_alloc() into separate source file

efi_random_alloc() is only used on arm64, but as it shares a source
file with efi_random_get_seed(), the latter will pull in the former

efi/libstub: Move efi_random_alloc() into separate source file

efi_random_alloc() is only used on arm64, but as it shares a source
file with efi_random_get_seed(), the latter will pull in the former
on other architectures as well.

Let's take advantage of the fact that libstub is a static library,
and so the linker will only incorporate objects that are needed to
satisfy dependencies in other objects. This means we can move the
random alloc code to a separate source file that gets built
unconditionally, but only used when needed.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

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efi/libstub/x86: Incorporate eboot.c into libstub

Most of the EFI stub source files of all architectures reside under
drivers/firmware/efi/libstub, where they share a Makefile with special
CFLAGS an

efi/libstub/x86: Incorporate eboot.c into libstub

Most of the EFI stub source files of all architectures reside under
drivers/firmware/efi/libstub, where they share a Makefile with special
CFLAGS and an include file with declarations that are only relevant
for stub code.

Currently, we carry a lot of stub specific stuff in linux/efi.h only
because eboot.c in arch/x86 needs them as well. So let's move eboot.c
into libstub/, and move the contents of eboot.h that we still care
about into efistub.h

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

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efi/libstub: Move memory map handling and allocation routines to mem.c

Create a new source file mem.c to keep the routines involved in memory
allocation and deallocation and manipulation of the EFI

efi/libstub: Move memory map handling and allocation routines to mem.c

Create a new source file mem.c to keep the routines involved in memory
allocation and deallocation and manipulation of the EFI memory map.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

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efi/libstub: Use hidden visibility for all source files

Instead of setting the visibility pragma for a small set of symbol
declarations that could result in absolute references that we cannot
suppor

efi/libstub: Use hidden visibility for all source files

Instead of setting the visibility pragma for a small set of symbol
declarations that could result in absolute references that we cannot
support in the stub, declare hidden visibility for all code in the
EFI stub, which is more robust and future proof.

To ensure that the #pragma is taken into account before any other
includes are processed, put it in a header file of its own and
include it via the compiler command line using the -include option.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

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efi/libstub/arm64: Use 1:1 mapping of RT services if property table exists

The UEFI spec defines (and deprecates) a misguided and shortlived
memory protection feature that is based on splitting memo

efi/libstub/arm64: Use 1:1 mapping of RT services if property table exists

The UEFI spec defines (and deprecates) a misguided and shortlived
memory protection feature that is based on splitting memory regions
covering PE/COFF executables into separate code and data regions,
without annotating them as belonging to the same executable image.
When the OS assigns the virtual addresses of these regions, it may
move them around arbitrarily, without taking into account that the
PE/COFF code sections may contain relative references into the data
sections, which means the relative placement of these segments has
to be preserved or the executable image will be corrupted.

The original workaround on arm64 was to ensure that adjacent regions
of the same type were mapped adjacently in the virtual mapping, but
this requires sorting of the memory map, which we would prefer to
avoid.

Considering that the native physical mapping of the PE/COFF images
does not suffer from this issue, let's preserve it at runtime, and
install it as the virtual mapping as well.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

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build, kcsan: Add KCSAN build exceptions

This blacklists several compilation units from KCSAN. See the respective
inline comments for the reasoning.

Signed-off-by: Marco Elver <elver@google.com>
Ac

build, kcsan: Add KCSAN build exceptions

This blacklists several compilation units from KCSAN. See the respective
inline comments for the reasoning.

Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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efi: Allow disabling PCI busmastering on bridges during boot

Add an option to disable the busmaster bit in the control register on
all PCI bridges before calling ExitBootServices() and passing contr

efi: Allow disabling PCI busmastering on bridges during boot

Add an option to disable the busmaster bit in the control register on
all PCI bridges before calling ExitBootServices() and passing control
to the runtime kernel. System firmware may configure the IOMMU to prevent
malicious PCI devices from being able to attack the OS via DMA. However,
since firmware can't guarantee that the OS is IOMMU-aware, it will tear
down IOMMU configuration when ExitBootServices() is called. This leaves
a window between where a hostile device could still cause damage before
Linux configures the IOMMU again.

If CONFIG_EFI_DISABLE_PCI_DMA is enabled or "efi=disable_early_pci_dma"
is passed on the command line, the EFI stub will clear the busmaster bit
on all PCI bridges before ExitBootServices() is called. This will
prevent any malicious PCI devices from being able to perform DMA until
the kernel reenables busmastering after configuring the IOMMU.

This option may cause failures with some poorly behaved hardware and
should not be enabled without testing. The kernel commandline options
"efi=disable_early_pci_dma" or "efi=no_disable_early_pci_dma" may be
used to override the default. Note that PCI devices downstream from PCI
bridges are disconnected from their drivers first, using the UEFI
driver model API, so that DMA can be disabled safely at the bridge
level.

[ardb: disconnect PCI I/O handles first, as suggested by Arvind]

Co-developed-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Matthew Garrett <matthewgarrett@google.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20200103113953.9571-18-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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x86: efi/random: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

Invoke the EFI_RNG_PROTOCOL protocol in the context of the x86 EFI stub,
same as is done on arm/arm64 since commit 568bc4e87033 ("

x86: efi/random: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

Invoke the EFI_RNG_PROTOCOL protocol in the context of the x86 EFI stub,
same as is done on arm/arm64 since commit 568bc4e87033 ("efi/arm*/libstub:
Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table"). Within the stub,
a Linux-specific RNG seed UEFI config table will be seeded. The EFI routines
in the core kernel will pick that up later, yet still early during boot,
to seed the kernel entropy pool. If CONFIG_RANDOM_TRUST_BOOTLOADER, entropy
is credited for this seed.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

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efi: libstub/arm: Account for firmware reserved memory at the base of RAM

The EFI stubloader for ARM starts out by allocating a 32 MB window
at the base of RAM, in order to ensure that the decompres

efi: libstub/arm: Account for firmware reserved memory at the base of RAM

The EFI stubloader for ARM starts out by allocating a 32 MB window
at the base of RAM, in order to ensure that the decompressor (which
blindly copies the uncompressed kernel into that window) does not
overwrite other allocations that are made while running in the context
of the EFI firmware.

In some cases, (e.g., U-Boot running on the Raspberry Pi 2), this is
causing boot failures because this initial allocation conflicts with
a page of reserved memory at the base of RAM that contains the SMP spin
tables and other pieces of firmware data and which was put there by
the bootloader under the assumption that the TEXT_OFFSET window right
below the kernel is only used partially during early boot, and will be
left alone once the memory reservations are processed and taken into
account.

So let's permit reserved memory regions to exist in the region starting
at the base of RAM, and ending at TEXT_OFFSET - 5 * PAGE_SIZE, which is
the window below the kernel that is not touched by the early boot code.

Tested-by: Guillaume Gardet <Guillaume.Gardet@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Chester Lin <clin@suse.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: https://lkml.kernel.org/r/20191029173755.27149-5-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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efi/arm/arm64: Makefile: Replace -pg with CC_FLAGS_FTRACE

In preparation for arm64 supporting ftrace built on other compiler
options, let's have Makefiles remove the $(CC_FLAGS_FTRACE) flags,
whatev

efi/arm/arm64: Makefile: Replace -pg with CC_FLAGS_FTRACE

In preparation for arm64 supporting ftrace built on other compiler
options, let's have Makefiles remove the $(CC_FLAGS_FTRACE) flags,
whatever these maybe, rather than assuming '-pg'.

While at it, fix arm32 as well. There should be no functional change as
a result of this patch.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>

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efi/libstub/arm: Omit unneeded stripping of ksymtab/kcrctab sections

Commit f922c4abdf764 ("module: allow symbol exports to be disabled")
introduced a way to inhibit generation of kcrctab/ksymtab se

efi/libstub/arm: Omit unneeded stripping of ksymtab/kcrctab sections

Commit f922c4abdf764 ("module: allow symbol exports to be disabled")
introduced a way to inhibit generation of kcrctab/ksymtab sections
when building ordinary kernel code to be used in a different execution
context (decompressor, EFI stub, etc)

That means we no longer have to strip those sections explicitly when
building the EFI libstub objects, so drop this from the Makefile.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190328193429.21373-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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efi/libstub: Refactor the cmd_stubcopy Makefile command

It took me a while to understand what is going on in the nested
if-blocks.

Simplify it by removing unneeded code.

- if_changed automatical

efi/libstub: Refactor the cmd_stubcopy Makefile command

It took me a while to understand what is going on in the nested
if-blocks.

Simplify it by removing unneeded code.

- if_changed automatically adds 'set -e', so any failure in the
series of commands makes it immediately fail as a whole.
So, the outer if block is entirely redundant.

- Since commit 9c2af1c7377a ("kbuild: add .DELETE_ON_ERROR special target"),
GNU Make automatically deletes the target on any failure
in its recipe. The explicit 'rm -f $@' is redundant.

- Surrounding commands with ( ) will spawn a subshell to execute them
in it, but it is rarely useful to do so.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.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/20190328193429.21373-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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efi/fdt: Apply more cleanups

Apply a number of cleanups:

- Introduce fdt_setprop_*var() helper macros to simplify and shorten repetitive
sequences - this also makes it less likely that the wron

efi/fdt: Apply more cleanups

Apply a number of cleanups:

- Introduce fdt_setprop_*var() helper macros to simplify and shorten repetitive
sequences - this also makes it less likely that the wrong variable size is
passed in. This change makes a lot of the property-setting calls single-line
and easier to read.

- Harmonize comment style: capitalization, punctuation, whitespaces, etc.

- Fix some whitespace noise in the libstub Makefile which I happened to notice.

- Use the standard tabular initialization style:

- map.map = &runtime_map;
- map.map_size = &map_size;
- map.desc_size = &desc_size;
- map.desc_ver = &desc_ver;
- map.key_ptr = &mmap_key;
- map.buff_size = &buff_size;

+ map.map = &runtime_map;
+ map.map_size = &map_size;
+ map.desc_size = &desc_size;
+ map.desc_ver = &desc_ver;
+ map.key_ptr = &mmap_key;
+ map.buff_size = &buff_size;

- Use tabular structure definition for better readability.

- Make all pr*() lines single-line, even if they marginally exceed 80 cols - this
makes them visually less intrusive.

- Unbreak line breaks into single lines when the length exceeds 80 cols only
marginally, for better readability.

- Move assignment closer to the actual usage site.

- Plus some other smaller cleanups, spelling fixes, etc.

No change in functionality intended.

[ ardb: move changes to upstream libfdt into local header. ]

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Lee Jones <lee.jones@linaro.org>
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/20190202094119.13230-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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efi/libstub: Disable some warnings for x86{,_64}

When building the kernel with Clang, some disabled warnings appear
because this Makefile overrides KBUILD_CFLAGS for x86{,_64}. Add them to
this list

efi/libstub: Disable some warnings for x86{,_64}

When building the kernel with Clang, some disabled warnings appear
because this Makefile overrides KBUILD_CFLAGS for x86{,_64}. Add them to
this list so that the build is clean again.

-Wpointer-sign was disabled for the whole kernel before the beginning of Git history.

-Waddress-of-packed-member was disabled for the whole kernel and for
the early boot code in these commits:

bfb38988c51e ("kbuild: clang: Disable 'address-of-packed-member' warning")
20c6c1890455 ("x86/boot: Disable the address-of-packed-member compiler warning").

-Wgnu was disabled for the whole kernel and for the early boot code in
these commits:

61163efae020 ("kbuild: LLVMLinux: Add Kbuild support for building kernel with Clang")
6c3b56b19730 ("x86/boot: Disable Clang warnings about GNU extensions").

[ mingo: Made the changelog more readable. ]

Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
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: Marc Zyngier <marc.zyngier@arm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.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/20181129171230.18699-8-ard.biesheuvel@linaro.org
Link: https://github.com/ClangBuiltLinux/linux/issues/112
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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efi/libstub: arm: support building with clang

When building with CONFIG_EFI and CONFIG_EFI_STUB on ARM, the libstub
Makefile would use -mno-single-pic-base without checking it was
supported by the c

efi/libstub: arm: support building with clang

When building with CONFIG_EFI and CONFIG_EFI_STUB on ARM, the libstub
Makefile would use -mno-single-pic-base without checking it was
supported by the compiler. As the ARM (32-bit) clang backend does not
support this flag, the build would fail.

This changes the Makefile to check the compiler's support for
-mno-single-pic-base before using it, similar to c1c386681bd7 ("ARM:
8767/1: add support for building ARM kernel with clang").

Signed-off-by: Alistair Strachan <astrachan@google.com>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

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module: allow symbol exports to be disabled

To allow existing C code to be incorporated into the decompressor or the
UEFI stub, introduce a CPP macro that turns all EXPORT_SYMBOL_xxx
declarations in

module: allow symbol exports to be disabled

To allow existing C code to be incorporated into the decompressor or the
UEFI stub, introduce a CPP macro that turns all EXPORT_SYMBOL_xxx
declarations into nops, and #define it in places where such exports are
undesirable. Note that this gets rid of a rather dodgy redefine of
linux/export.h's header guard.

Link: http://lkml.kernel.org/r/20180704083651.24360-3-ard.biesheuvel@linaro.org
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morris <james.morris@microsoft.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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efi/libstub: Only disable stackleak plugin for arm64

arm64 uses the full KBUILD_CFLAGS for building libstub as opposed
to x86 which doesn't. This means that x86 doesn't pick up
the gcc-plugins. We n

efi/libstub: Only disable stackleak plugin for arm64

arm64 uses the full KBUILD_CFLAGS for building libstub as opposed
to x86 which doesn't. This means that x86 doesn't pick up
the gcc-plugins. We need to disable the stackleak plugin but
doing this unconditionally breaks x86 build since it doesn't
have any plugins. Switch to disabling the stackleak plugin for
arm64 only.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

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arm64: Add support for STACKLEAK gcc plugin

This adds support for the STACKLEAK gcc plugin to arm64 by implementing
stackleak_check_alloca(), based heavily on the x86 version, and adding the
two hel

arm64: Add support for STACKLEAK gcc plugin

This adds support for the STACKLEAK gcc plugin to arm64 by implementing
stackleak_check_alloca(), based heavily on the x86 version, and adding the
two helpers used by the stackleak common code: current_top_of_stack() and
on_thread_stack(). The stack erasure calls are made at syscall returns.
Additionally, this disables the plugin in hypervisor and EFI stub code,
which are out of scope for the protection.

Acked-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

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efi: Use string literals for efi_char16_t variable initializers

Now that we unambiguously build the entire kernel with -fshort-wchar,
it is no longer necessary to open code efi_char16_t[] initialize

efi: Use string literals for efi_char16_t variable initializers

Now that we unambiguously build the entire kernel with -fshort-wchar,
it is no longer necessary to open code efi_char16_t[] initializers as
arrays of characters, and we can move to the L"xxx" notation instead.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
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/20180312084500.10764-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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efi: call get_event_log before ExitBootServices

With TPM 2.0 specification, the event logs may only be accessible by
calling an EFI Boot Service. Modify the EFI stub to copy the log area to
a new Li

efi: call get_event_log before ExitBootServices

With TPM 2.0 specification, the event logs may only be accessible by
calling an EFI Boot Service. Modify the EFI stub to copy the log area to
a new Linux-specific EFI configuration table so it remains accessible
once booted.

When calling this service, it is possible to specify the expected format
of the logs: TPM 1.2 (SHA1) or TPM 2.0 ("Crypto Agile"). For now, only the
first format is retrieved.

Signed-off-by: Thiebaud Weksteen <tweek@google.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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efi/libstub: arm: omit sorting of the UEFI memory map

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

efi/libstub: arm: omit sorting of the UEFI memory map

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>

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efi/libstub: Enable reset attack mitigation

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 memo

efi/libstub: Enable reset attack mitigation

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>

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