1
0
Fork 0
mirror of synced 2025-03-06 20:59:54 +01:00
Commit graph

571 commits

Author SHA1 Message Date
Linus Torvalds
3894840a7a ARM updates for v6.11-rc1
- ftrace: don't assume stack frames are contiguous in memory
 - remove unused mod_inwind_map structure
 - spelling fixes
 - allow use of LD dead code/data elimination
 - fix callchain_trace() return value
 - add support for stackleak gcc plugin
 - correct some reset asm function prototypes for CFI
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEuNNh8scc2k/wOAE+9OeQG+StrGQFAmakrP8ACgkQ9OeQG+St
 rGRptA//Zr3FixLWZQ5FfHHaoEMAwIr76dwputg30Nvl4uFaYpc0XhksSfz3oSHM
 S/n2j4ognu9DZgEfoEUuCWgsZGBlt95Zrs1/XyD2aS6emXaL85QlCNlFtiRGUGUD
 i5uZyp7hnKjLixSGe+PZtSMHWId1+OQP4++EyAWPo5iejTgA61u7TWRYuP7Z8n93
 u2mKj2Zd4fHOiV5tUuT9gWovJqN9UiHRC+SVlm81bTftV/fAO0YZcMZDgRVa8KGx
 QheCYjJqS7ucDxvo8zIVbgQWdUobFwMZkLP049txv7zYGX888JF9ALY/Bb0GrwLg
 MUjxmiQMe7Rh775BUQP8zrhXnSEU4YDpeNCuPu72dAOvI0mOQXRB7HU43PQElHLV
 KuRAo4kTnjARGxfZ8B8kBACE63pOp7FemqGABPHx+//RDJDwgmzKv1NOKTWLBh6V
 bPxAmTm6VzqV5ft2c3+D+cWOUEG/ozgIwXdi1jUPlvjznxawjOkA9eWtaGeFIMAB
 cd8wH6cC6hOututO8ji+zOEo72zsnQe5Kre/0bTYIV7ggZpyR7rjc2i45TrUyMyS
 arvm4BLBJWM/t7rmCpKZKbtylkS5a4tzaXYFVcbdxPReGuxy6x5N50xFuHcbas5k
 I+Wkm+RohB2eXgp17Ap1N1fhjiAWfK5V+0LZ5KkrPg/01r/m6e0=
 =8sd2
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux

Pull ARM updates from Russell King:

 - ftrace: don't assume stack frames are contiguous in memory

 - remove unused mod_inwind_map structure

 - spelling fixes

 - allow use of LD dead code/data elimination

 - fix callchain_trace() return value

 - add support for stackleak gcc plugin

 - correct some reset asm function prototypes for CFI

[ Missed the merge window because Russell forgot to push out ]

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rmk/linux:
  ARM: 9408/1: mm: CFI: Fix some erroneous reset prototypes
  ARM: 9407/1: Add support for STACKLEAK gcc plugin
  ARM: 9406/1: Fix callchain_trace() return value
  ARM: 9404/1: arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION
  ARM: 9403/1: Alpine: Spelling s/initialiing/initializing/
  ARM: 9402/1: Kconfig: Spelling s/Cortex A-/Cortex-A/
  ARM: 9400/1: Remove unused struct 'mod_unwind_map'
2024-07-29 10:33:51 -07:00
Linus Torvalds
c9f33436d8 RISC-V Patches for the 6.11 Merge Window, Part 2
* Support for NUMA (via SRAT and SLIT), console output (via SPCR), and
   cache info (via PPTT) on ACPI-based systems.
 * The trap entry/exit code no longer breaks the return address stack
   predictor on many systems, which results in an improvement to trap
   latency.
 * Support for HAVE_ARCH_STACKLEAK.
 * The sv39 linear map has been extended to support 128GiB mappings.
 * The frequency of the mtime CSR is now visible via hwprobe.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCAAxFiEEKzw3R0RoQ7JKlDp6LhMZ81+7GIkFAmaj2EYTHHBhbG1lckBk
 YWJiZWx0LmNvbQAKCRAuExnzX7sYiVG3D/9kNHTI09iPDJd6fTChE3cpMxy7xXXE
 URX3Avu+gYsJmIbYyg4RnQ8FGFN7icKBCrQqs7JmLliU0NU+YMcCcjsJA2QaivbD
 VAlaex1qNcvNGteHrpbqhr3Zs4zw8GlBkB3KFTLyPAp61bybGo0a/A5ONJ7ScQIW
 RWHewAPgb86cQ0Q34JpO87TqvMM0KMvhQP5dip+olaFjLRBzhXmGFZfHqA80kTWl
 0ytYclVCHZMtO/5mnQpuIOVs1IKw9L4wa0sivOQF0iLTqfKDFALa6yZsThHA/w3e
 JVuBAdQhcPZ3fgO2fUfJPlW16GmRC2/tdiFg5NFw8k4vo7DYBwX55ztPKXqDrJDM
 8ah85IeLiPar/A/uHdn6bPjK+aGMuzklKF50r62XXAc2fL8mza1sdvKCVOy2EOLn
 JyGI9c/10KpvN/DW8g7hPefhvbx4+tCKkFcPqf++VQha6W8cQdCKi+Li0Pm8TTnp
 XPQjIvSlDDG1Pl4ofgBSFoyB8pkBXNzvv8NZp+YYtnqSOLAKaZuP+KwA8TwHdvGM
 pdCXcL3KHiLy4/pJWEoNTutD0mbJ7PUIb2P/KkjqYDgp4F1n0Hg+/aeSIp+7a4Pv
 yTBctIGxrlriQMIdtWCR8tyhcPP4pDpGYkW0K15EE16G0NK0fjD89LEXYqT6ae2R
 C0QgiwnVe/eopg==
 =zeUn
 -----END PGP SIGNATURE-----

Merge tag 'riscv-for-linus-6.11-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull more RISC-V updates from Palmer Dabbelt:

 - Support for NUMA (via SRAT and SLIT), console output (via SPCR), and
   cache info (via PPTT) on ACPI-based systems.

 - The trap entry/exit code no longer breaks the return address stack
   predictor on many systems, which results in an improvement to trap
   latency.

 - Support for HAVE_ARCH_STACKLEAK.

 - The sv39 linear map has been extended to support 128GiB mappings.

 - The frequency of the mtime CSR is now visible via hwprobe.

* tag 'riscv-for-linus-6.11-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (21 commits)
  RISC-V: Provide the frequency of time CSR via hwprobe
  riscv: Extend sv39 linear mapping max size to 128G
  riscv: enable HAVE_ARCH_STACKLEAK
  riscv: signal: Remove unlikely() from WARN_ON() condition
  riscv: Improve exception and system call latency
  RISC-V: Select ACPI PPTT drivers
  riscv: cacheinfo: initialize cacheinfo's level and type from ACPI PPTT
  riscv: cacheinfo: remove the useless input parameter (node) of ci_leaf_init()
  RISC-V: ACPI: Enable SPCR table for console output on RISC-V
  riscv: boot: remove duplicated targets line
  trace: riscv: Remove deprecated kprobe on ftrace support
  riscv: cpufeature: Extract common elements from extension checking
  riscv: Introduce vendor variants of extension helpers
  riscv: Add vendor extensions to /proc/cpuinfo
  riscv: Extend cpufeature.c to detect vendor extensions
  RISC-V: run savedefconfig for defconfig
  RISC-V: hwprobe: sort EXT_KEY()s in hwprobe_isa_ext0() alphabetically
  ACPI: NUMA: replace pr_info with pr_debug in arch_acpi_numa_init
  ACPI: NUMA: change the ACPI_NUMA to a hidden option
  ACPI: NUMA: Add handler for SRAT RINTC affinity structure
  ...
2024-07-27 10:14:34 -07:00
Jisheng Zhang
b5db73fb18
riscv: enable HAVE_ARCH_STACKLEAK
Add support for the stackleak feature. Whenever the kernel returns to user
space the kernel stack is filled with a poison value.

At the same time, disables the plugin in EFI stub code because EFI stub
is out of scope for the protection.

Tested on qemu and milkv duo:
/ # echo STACKLEAK_ERASING > /sys/kernel/debug/provoke-crash/DIRECT
[   38.675575] lkdtm: Performing direct entry STACKLEAK_ERASING
[   38.678448] lkdtm: stackleak stack usage:
[   38.678448]   high offset: 288 bytes
[   38.678448]   current:     496 bytes
[   38.678448]   lowest:      1328 bytes
[   38.678448]   tracked:     1328 bytes
[   38.678448]   untracked:   448 bytes
[   38.678448]   poisoned:    14312 bytes
[   38.678448]   low offset:  8 bytes
[   38.689887] lkdtm: OK: the rest of the thread stack is properly erased

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20240623235316.2010-1-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2024-07-26 05:50:47 -07:00
Linus Torvalds
bba959f477 EFI fixes for v6.11 #1
- Wipe screen_info after allocating it from the heap - used by arm32 and
   EFI zboot, other EFI architectures allocate it statically
 
 - Revert to allocating boot_params from the heap on x86 when entering
   via the native PE entrypoint, to work around a regression on older
   Dell hardware
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQQm/3uucuRGn1Dmh0wbglWLn0tXAUCZqDiNgAKCRAwbglWLn0t
 XBU/AQC1Qm7UFhBR6agbR1WMGcrmByR99t9bLNqOFHZxAJIvfQEAgCXcO3LpLfG5
 SfCAZFIdwoK48Avdq2OBktz82JKXgQ8=
 =ujzu
 -----END PGP SIGNATURE-----

Merge tag 'efi-fixes-for-v6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI fixes from Ard Biesheuvel:

 - Wipe screen_info after allocating it from the heap - used by arm32
   and EFI zboot, other EFI architectures allocate it statically

 - Revert to allocating boot_params from the heap on x86 when entering
   via the native PE entrypoint, to work around a regression on older
   Dell hardware

* tag 'efi-fixes-for-v6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  x86/efistub: Revert to heap allocated boot_params for PE entrypoint
  efi/libstub: Zero initialize heap allocated struct screen_info
2024-07-25 12:55:21 -07:00
Linus Torvalds
a362ade892 LoongArch changes for v6.11
1, Define __ARCH_WANT_NEW_STAT in unistd.h;
 2, Always enumerate MADT and setup logical-physical CPU mapping;
 3, Add irq_work support via self IPIs;
 4, Add RANDOMIZE_KSTACK_OFFSET support;
 5, Add ARCH_HAS_PTE_DEVMAP support;
 6, Add ARCH_HAS_DEBUG_VM_PGTABLE support;
 7, Add writecombine support for DMW-based ioremap();
 8, Add architectural preparation for CPUFreq;
 9, Add ACPI standard hardware register based S3 support;
 10, Add support for relocating the kernel with RELR relocation;
 11, Some bug fixes and other small changes.
 -----BEGIN PGP SIGNATURE-----
 
 iQJKBAABCAA0FiEEzOlt8mkP+tbeiYy5AoYrw/LiJnoFAmabzOsWHGNoZW5odWFj
 YWlAa2VybmVsLm9yZwAKCRAChivD8uImeqssD/9AG3WGb25R4IvgnZYuRCxpXsLk
 Qrj4YSPazaTLrQBWk1g+KqcBLe+jZV4zmnz0H93qoOpyMDwsmExugDug7QCKiBl1
 olVZ0CeQ6dyMHAnFjTgy29KcyJRFith4jXFGq6kpNa80pezsXz7b869GkLZflZfy
 W9hALfcaxB4kx+z4HXblbOIsfzVwh2eBD/nkWukBG28CPMQ7pV4TtejIqSd9kDC5
 LQjVQhjyrDgR3EPJEzr+48/hgFB6cZ8fmfv5JVTu+rQMngUldxDijj8xfoIUgIjN
 2khFc2Orx5RVyIuBxtLKWf70HD9xXC0fqUVjFEn0Yn5i1JVLoMdqjownSWvPy3t7
 z3V0E0VaYUdLgA3GeA5Fw1uZbORlocAZbA5B8bXY2foNfwPwLlGpNiyNiqx5kQmQ
 O+9jQJqdrZZ18wXEW8sR8AnT5+lzIQdv1GlkYt2f5a1rjMZwHtPZI4aPRDojPo/3
 Fv0Q1+2XVnbPngzJJz9tlYCzt5iuY9z7DwsnbEBSiLZRapJ9ZECmJjSGnnR/fLLS
 ifdyooua8bviMwzmUEmfSgPRHyTZs+BjkD7AQ4xyRDAv0T2d9sDwkAWYBcViTslF
 awe6+x+zn6yXekhiloN8L+3HJ67bYojXmLciNqvFcVtSNgJQpXBjLDO9orCbNqmw
 ISxNA0GbR+eWGMdvCA==
 =bla1
 -----END PGP SIGNATURE-----

Merge tag 'loongarch-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

Pull LoongArch updates from Huacai Chen:

 - Define __ARCH_WANT_NEW_STAT in unistd.h

 - Always enumerate MADT and setup logical-physical CPU mapping

 - Add irq_work support via self IPIs

 - Add RANDOMIZE_KSTACK_OFFSET support

 - Add ARCH_HAS_PTE_DEVMAP support

 - Add ARCH_HAS_DEBUG_VM_PGTABLE support

 - Add writecombine support for DMW-based ioremap()

 - Add architectural preparation for CPUFreq

 - Add ACPI standard hardware register based S3 support

 - Add support for relocating the kernel with RELR relocation

 - Some bug fixes and other small changes

* tag 'loongarch-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson:
  LoongArch: Make the users of larch_insn_gen_break() constant
  LoongArch: Check TIF_LOAD_WATCH to enable user space watchpoint
  LoongArch: Use rustc option -Zdirect-access-external-data
  LoongArch: Add support for relocating the kernel with RELR relocation
  LoongArch: Remove a redundant checking in relocator
  LoongArch: Use correct API to map cmdline in relocate_kernel()
  LoongArch: Automatically disable KASLR for hibernation
  LoongArch: Add ACPI standard hardware register based S3 support
  LoongArch: Add architectural preparation for CPUFreq
  LoongArch: Add writecombine support for DMW-based ioremap()
  LoongArch: Add ARCH_HAS_DEBUG_VM_PGTABLE support
  LoongArch: Add ARCH_HAS_PTE_DEVMAP support
  LoongArch: Add RANDOMIZE_KSTACK_OFFSET support
  LoongArch: Add irq_work support via self IPIs
  LoongArch: Always enumerate MADT and setup logical-physical CPU mapping
  LoongArch: Define __ARCH_WANT_NEW_STAT in unistd.h
2024-07-22 13:44:22 -07:00
Huacai Chen
8e02c3b782 LoongArch: Add writecombine support for DMW-based ioremap()
Currently, only TLB-based ioremap() support writecombine, so add the
counterpart for DMW-based ioremap() with help of DMW2. The base address
(WRITECOMBINE_BASE) is configured as 0xa000000000000000.

DMW3 is unused by kernel now, however firmware may leave garbage in them
and interfere kernel's address mapping. So clear it as necessary.

BTW, centralize the DMW configuration to macro SETUP_DMWINS.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-07-20 22:40:59 +08:00
Ard Biesheuvel
ae835a96d7 x86/efistub: Revert to heap allocated boot_params for PE entrypoint
This is a partial revert of commit

  8117961d98f ("x86/efi: Disregard setup header of loaded image")

which triggers boot issues on older Dell laptops. As it turns out,
switching back to a heap allocation for the struct boot_params
constructed by the EFI stub works around this, even though it is unclear
why.

Cc: Christian Heusel <christian@heusel.eu>
Reported-by: <mavrix#kernel@simplelogin.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-18 23:05:02 +02:00
Qiang Ma
ee8b8f5d83 efi/libstub: Zero initialize heap allocated struct screen_info
After calling uefi interface allocate_pool to apply for memory, we
should clear 0 to prevent the possibility of using random values.

Signed-off-by: Qiang Ma <maqianga@uniontech.com>
Cc: <stable@vger.kernel.org> # v6.6+
Fixes: 732ea9db9d ("efi: libstub: Move screen_info handling to common code")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-17 22:51:20 +02:00
Kees Cook
887c4cf559 efi: Rename efi_early_memdesc_ptr() to efi_memdesc_ptr()
The "early" part of the helper's name isn't accurate[1]. Drop it in
preparation for adding a new (not early) usage.

Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/lkml/CAMj1kXEyDjH0uu3Z4eBesV3PEnKGi5ArXXMp7R-hn8HdRytiPg@mail.gmail.com [1]
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-12 10:06:01 +02:00
Ard Biesheuvel
12a01f66f0 arm64/efistub: Clean up KASLR logic
Clean up some redundant code in the KASLR placement handling logic. No
functional change intended.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-10 12:22:46 +02:00
Ard Biesheuvel
ebf5a79acf x86/efistub: Drop redundant clearing of BSS
As it turns out, clearing the BSS was not the right fix for the issue
that was ultimately fixed by commit decd347c2a ("x86/efistub:
Reinstate soft limit for initrd loading"), and given that the Windows
EFI loader becomes very unhappy when entered with garbage in BSS, this
is one thing that x86 PC EFI implementations can be expected to get
right.

So drop it from the pure PE entrypoint. The handover protocol entrypoint
still needs this - it is used by the flaky distro bootloaders that
barely implement PE/COFF at all.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-08 10:17:45 +02:00
Ard Biesheuvel
fb318ca0a5 x86/efistub: Avoid returning EFI_SUCCESS on error
The fail label is only used in a situation where the previous EFI API
call succeeded, and so status will be set to EFI_SUCCESS. Fix this, by
dropping the goto entirely, and call efi_exit() with the correct error
code.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-08 10:17:45 +02:00
Aditya Garg
71e49eccdc x86/efistub: Call Apple set_os protocol on dual GPU Intel Macs
0c18184de9 ("platform/x86: apple-gmux: support MMIO gmux on T2 Macs")
brought support for T2 Macs in apple-gmux. But in order to use dual GPU,
the integrated GPU has to be enabled. On such dual GPU EFI Macs, the EFI
stub needs to report that it is booting macOS in order to prevent the
firmware from disabling the iGPU.

This patch is also applicable for some non T2 Intel Macs.

Based on this patch for GRUB by Andreas Heider <andreas@heider.io>:
https://lists.gnu.org/archive/html/grub-devel/2013-12/msg00442.html

Credits also goto Kerem Karabay <kekrby@gmail.com> for helping porting
the patch to the Linux kernel.

Cc: Orlando Chamberlain <orlandoch.dev@gmail.com>
Signed-off-by: Aditya Garg <gargaditya08@live.com>
[ardb: limit scope using list of DMI matches provided by Lukas and Orlando]
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Aditya Garg <gargaditya08@live.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-08 10:17:45 +02:00
Ard Biesheuvel
cd6193877c x86/efistub: Enable SMBIOS protocol handling for x86
The smbios.c source file is not currently included in the x86 build, and
before we can do so, it needs some tweaks to build correctly in
combination with the EFI mixed mode support.

Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-08 10:17:44 +02:00
Jinjie Ruan
2335c9cb83 ARM: 9407/1: Add support for STACKLEAK gcc plugin
Add the STACKLEAK gcc plugin to arm32 by adding the helper used by
stackleak common code: on_thread_stack(). It initialize the stack with the
poison value before returning from system calls which improves the kernel
security. Additionally, this disables the plugin in EFI stub code and
decompress code, which are out of scope for the protection.

Before the test on Qemu versatilepb board:
	# echo STACKLEAK_ERASING  > /sys/kernel/debug/provoke-crash/DIRECT
	lkdtm: Performing direct entry STACKLEAK_ERASING
	lkdtm: XFAIL: stackleak is not supported on this arch (HAVE_ARCH_STACKLEAK=n)

After:
	# echo STACKLEAK_ERASING  > /sys/kernel/debug/provoke-crash/DIRECT
	lkdtm: Performing direct entry STACKLEAK_ERASING
	lkdtm: stackleak stack usage:
	  high offset: 80 bytes
	  current:     280 bytes
	  lowest:      696 bytes
	  tracked:     696 bytes
	  untracked:   192 bytes
	  poisoned:    7220 bytes
	  low offset:  4 bytes
	lkdtm: OK: the rest of the thread stack is properly erased

Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2024-07-02 09:18:43 +01:00
Ard Biesheuvel
0dad9ee3c1 efistub/smbios: Simplify SMBIOS enumeration API
Update the efi_get_smbios_string() macro to take a pointer to the entire
record struct rather than the header. This removes the need to pass the
type explicitly, as it can be inferred from the typed pointer. Also,
drop 'type' from the prototype of __efi_get_smbios_string(), as it is
never referenced.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-02 00:42:04 +02:00
Ard Biesheuvel
37aee82c21 x86/efi: Drop support for fake EFI memory maps
Between kexec and confidential VM support, handling the EFI memory maps
correctly on x86 is already proving to be rather difficult (as opposed
to other EFI architectures which manage to never modify the EFI memory
map to begin with)

EFI fake memory map support is essentially a development hack (for
testing new support for the 'special purpose' and 'more reliable' EFI
memory attributes) that leaked into production code. The regions marked
in this manner are not actually recognized as such by the firmware
itself or the EFI stub (and never have), and marking memory as 'more
reliable' seems rather futile if the underlying memory is just ordinary
RAM.

Marking memory as 'special purpose' in this way is also dubious, but may
be in use in production code nonetheless. However, the same should be
achievable by using the memmap= command line option with the ! operator.

EFI fake memmap support is not enabled by any of the major distros
(Debian, Fedora, SUSE, Ubuntu) and does not exist on other
architectures, so let's drop support for it.

Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-07-02 00:26:24 +02:00
Yuntao Liu
ed0f941022 ARM: 9404/1: arm32: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION
The current arm32 architecture does not yet support the
HAVE_LD_DEAD_CODE_DATA_ELIMINATION feature. arm32 is widely used in
embedded scenarios, and enabling this feature would be beneficial for
reducing the size of the kernel image.

In order to make this work, we keep the necessary tables by annotating
them with KEEP, also it requires further changes to linker script to KEEP
some tables and wildcard compiler generated sections into the right place.
When using ld.lld for linking, KEEP is not recognized within the OVERLAY
command, and Ard proposed a concise method to solve this problem.

It boots normally with defconfig, vexpress_defconfig and tinyconfig.

The size comparison of zImage is as follows:
defconfig       vexpress_defconfig      tinyconfig
5137712         5138024                 424192          no dce
5032560         4997824                 298384          dce
2.0%            2.7%                    29.7%           shrink

When using smaller config file, there is a significant reduction in the
size of the zImage.

We also tested this patch on a commercially available single-board
computer, and the comparison is as follows:
a15eb_config
2161384         no dce
2092240         dce
3.2%            shrink

The zImage size has been reduced by approximately 3.2%, which is 70KB on
2.1M.

Signed-off-by: Yuntao Liu <liuyuntao12@huawei.com>
Tested-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2024-06-10 12:01:33 +01:00
Linus Torvalds
a34adf6010 EFI fixes for v6.10 #2
- Ensure that .discard sections are really discarded in the EFI zboot
   image build
 - Return proper error numbers from efi-pstore
 - Add __nocfi annotations to EFI runtime wrappers
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQQm/3uucuRGn1Dmh0wbglWLn0tXAUCZmAmwwAKCRAwbglWLn0t
 XNbNAQDsnOTRK4Azr0rqHUvOoB2g+0XlIL9yR+r5MwV8lAdL+QD9GJpX7p7pzT4q
 aT4zzzoS1h9FFUNTDtE7by18bDBElgI=
 =RxkM
 -----END PGP SIGNATURE-----

Merge tag 'efi-fixes-for-v6.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI fixes from Ard Biesheuvel:

 - Ensure that .discard sections are really discarded in the EFI zboot
   image build

 - Return proper error numbers from efi-pstore

 - Add __nocfi annotations to EFI runtime wrappers

* tag 'efi-fixes-for-v6.10-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efi: Add missing __nocfi annotations to runtime wrappers
  efi: pstore: Return proper errors on UEFI failures
  efi/libstub: zboot.lds: Discard .discard sections
2024-06-06 09:39:36 -07:00
Ard Biesheuvel
290be0a402 Merge branch 'efi/next' into efi/urgent 2024-06-04 19:31:03 +02:00
Jiaxun Yang
beb2800074 LoongArch: Fix entry point in kernel image header
Currently kernel entry in head.S is in DMW address range, firmware is
instructed to jump to this address after loading the kernel image.

However kernel should not make any assumption on firmware's DMW
setting, thus the entry point should be a physical address falls into
direct translation region.

Fix by converting entry address to physical and amend entry calculation
logic in libstub accordingly.

BTW, use ABSOLUTE() to calculate variables to make Clang/LLVM happy.

Cc: stable@vger.kernel.org
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-06-03 15:45:53 +08:00
Nathan Chancellor
5134acb15d efi/libstub: zboot.lds: Discard .discard sections
When building ARCH=loongarch defconfig + CONFIG_UNWINDER_ORC=y using
LLVM, there is a warning from ld.lld when linking the EFI zboot image
due to the use of unreachable() in number() in vsprintf.c:

  ld.lld: warning: drivers/firmware/efi/libstub/lib.a(vsprintf.stub.o):(.discard.unreachable+0x0): has non-ABS relocation R_LARCH_32_PCREL against symbol ''

If the compiler cannot eliminate the default case for any reason, the
.discard.unreachable section will remain in the final binary but the
entire point of any section prefixed with .discard is that it is only
used at compile time, so it can be discarded via /DISCARD/ in a linker
script. The asm-generic vmlinux.lds.h includes .discard and .discard.*
in the COMMON_DISCARDS macro but that is not used for zboot.lds, as it
is not a kernel image linker script.

Add .discard and .discard.* to /DISCARD/ in zboot.lds, so that any
sections meant to be discarded at link time are not included in the
final zboot image. This issue is not specific to LoongArch, it is just
the first architecture to select CONFIG_OBJTOOL, which defines
annotate_unreachable() as an asm statement to add the
.discard.unreachable section, and use the EFI stub.

Closes: https://github.com/ClangBuiltLinux/linux/issues/2023
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-05-23 09:02:39 +02:00
Linus Torvalds
5499315668 EFI fixes for v6.10 #1
- Followup fix for the EFI boot sequence refactor, which may result in
   physical KASLR putting the kernel in a region which is being used for
   a special purpose via a command line argument.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQQm/3uucuRGn1Dmh0wbglWLn0tXAUCZks6+wAKCRAwbglWLn0t
 XCJzAQCOgl1bhfwU14U0KNjboeCcQKYrvD/6AmqM/UBsQyfB4gD+NuEAh2iKldeS
 +5DuaWE3/sMPrZlTpatNF5E99mu2uAQ=
 =Um+v
 -----END PGP SIGNATURE-----

Merge tag 'efi-fixes-for-v6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI fix from Ard Biesheuvel:

 - Followup fix for the EFI boot sequence refactor, which may result in
   physical KASLR putting the kernel in a region which is being used for
   a special purpose via a command line argument.

* tag 'efi-fixes-for-v6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  x86/efistub: Omit physical KASLR when memory reservations exist
2024-05-21 11:50:26 -07:00
Linus Torvalds
ff9a79307f Kbuild updates for v6.10
- Avoid 'constexpr', which is a keyword in C23
 
  - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
    'dt_binding_check'
 
  - Fix weak references to avoid GOT entries in position-independent
    code generation
 
  - Convert the last use of 'optional' property in arch/sh/Kconfig
 
  - Remove support for the 'optional' property in Kconfig
 
  - Remove support for Clang's ThinLTO caching, which does not work with
    the .incbin directive
 
  - Change the semantics of $(src) so it always points to the source
    directory, which fixes Makefile inconsistencies between upstream and
    downstream
 
  - Fix 'make tar-pkg' for RISC-V to produce a consistent package
 
  - Provide reasonable default coverage for objtool, sanitizers, and
    profilers
 
  - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.
 
  - Remove the last use of tristate choice in drivers/rapidio/Kconfig
 
  - Various cleanups and fixes in Kconfig
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCgAzFiEEbmPs18K1szRHjPqEPYsBB53g2wYFAmZFlGcVHG1hc2FoaXJv
 eUBrZXJuZWwub3JnAAoJED2LAQed4NsG8voQALC8NtFpduWVfLRj2Qg6Ll/xf1vX
 2igcTJEOFHkeqXLGoT8dTDKLEipUBUvKyguPq66CGwVTe2g6zy/nUSXeVtFrUsIa
 msLTi8FqhqUo5lodNvGMRf8qqmuqcvnXoiQwIocF92jtsFy14bhiFY+n4HfcFNjj
 GOKwqBZYQUwY/VVb090efc7RfS9c7uwABJSBelSoxg3AGZriwjGy7Pw5aSKGgVYi
 inqL1eR6qwPP6z7CgQWM99soP+zwybFZmnQrsD9SniRBI4rtAat8Ih5jQFaSUFUQ
 lk2w0NQBRFN88/uR2IJ2GWuIlQ74WeJ+QnCqVuQ59tV5zw90wqSmLzngfPD057Dv
 JjNuhk0UyXVtpIg3lRtd4810ppNSTe33b9OM4O2H846W/crju5oDRNDHcflUXcwm
 Rmn5ho1rb5QVzDVejJbgwidnUInSgJ9PZcvXQ/RJVZPhpgsBzAY9pQexG1G3hviw
 y9UDrt6KP6bF9tHjmolmtdIes9Pj0c4dN6/Rdj4HS4hIQ/GDar0tnwvOvtfUctNL
 orJlBsA6GeMmDVXKkR0ytOCWRYqWWbyt8g70RVKQJfuHX7/hGyAQPaQ2/u4mQhC2
 aevYfbNJMj0VDfGz81HDBKFtkc5n+Ite8l157dHEl2LEabkOkRdNVcn7SNbOvZmd
 ZCSnZ31h7woGfNho
 =D5B/
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Avoid 'constexpr', which is a keyword in C23

 - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
   'dt_binding_check'

 - Fix weak references to avoid GOT entries in position-independent code
   generation

 - Convert the last use of 'optional' property in arch/sh/Kconfig

 - Remove support for the 'optional' property in Kconfig

 - Remove support for Clang's ThinLTO caching, which does not work with
   the .incbin directive

 - Change the semantics of $(src) so it always points to the source
   directory, which fixes Makefile inconsistencies between upstream and
   downstream

 - Fix 'make tar-pkg' for RISC-V to produce a consistent package

 - Provide reasonable default coverage for objtool, sanitizers, and
   profilers

 - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.

 - Remove the last use of tristate choice in drivers/rapidio/Kconfig

 - Various cleanups and fixes in Kconfig

* tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (46 commits)
  kconfig: use sym_get_choice_menu() in sym_check_prop()
  rapidio: remove choice for enumeration
  kconfig: lxdialog: remove initialization with A_NORMAL
  kconfig: m/nconf: merge two item_add_str() calls
  kconfig: m/nconf: remove dead code to display value of bool choice
  kconfig: m/nconf: remove dead code to display children of choice members
  kconfig: gconf: show checkbox for choice correctly
  kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal
  Makefile: remove redundant tool coverage variables
  kbuild: provide reasonable defaults for tool coverage
  modules: Drop the .export_symbol section from the final modules
  kconfig: use menu_list_for_each_sym() in sym_check_choice_deps()
  kconfig: use sym_get_choice_menu() in conf_write_defconfig()
  kconfig: add sym_get_choice_menu() helper
  kconfig: turn defaults and additional prompt for choice members into error
  kconfig: turn missing prompt for choice members into error
  kconfig: turn conf_choice() into void function
  kconfig: use linked list in sym_set_changed()
  kconfig: gconf: use MENU_CHANGED instead of SYMBOL_CHANGED
  kconfig: gconf: remove debug code
  ...
2024-05-18 12:39:20 -07:00
Ard Biesheuvel
15aa8fb852 x86/efistub: Omit physical KASLR when memory reservations exist
The legacy decompressor has elaborate logic to ensure that the
randomized physical placement of the decompressed kernel image does not
conflict with any memory reservations, including ones specified on the
command line using mem=, memmap=, efi_fake_mem= or hugepages=, which are
taken into account by the kernel proper at a later stage.

When booting in EFI mode, it is the firmware's job to ensure that the
chosen range does not conflict with any memory reservations that it
knows about, and this is trivially achieved by using the firmware's
memory allocation APIs.

That leaves reservations specified on the command line, though, which
the firmware knows nothing about, as these regions have no other special
significance to the platform. Since commit

  a1b87d54f4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot")

these reservations are not taken into account when randomizing the
physical placement, which may result in conflicts where the memory
cannot be reserved by the kernel proper because its own executable image
resides there.

To avoid having to duplicate or reuse the existing complicated logic,
disable physical KASLR entirely when such overrides are specified. These
are mostly diagnostic tools or niche features, and physical KASLR (as
opposed to virtual KASLR, which is much more important as it affects the
memory addresses observed by code executing in the kernel) is something
we can live without.

Closes: https://lkml.kernel.org/r/FA5F6719-8824-4B04-803E-82990E65E627%40akamai.com
Reported-by: Ben Chaney <bchaney@akamai.com>
Fixes: a1b87d54f4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot")
Cc:  <stable@vger.kernel.org> # v6.1+
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-05-17 17:06:18 +02:00
Linus Torvalds
1b10b390d9 EFI updates for v6.10:
- Additional cleanup by Tim for the efivarfs variable name length
   confusion
 
 - Avoid freeing a bogus pointer when virtual remapping is omitted in the
   EFI boot stub
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQQm/3uucuRGn1Dmh0wbglWLn0tXAUCZkMPmAAKCRAwbglWLn0t
 XNw2AQC96tWvh7piDGw2LTGp4zqRcoe2LV09hNE8rgk63g+2LgEA81TOhEKwpeie
 23GI9WiEABdRT8kt6ebuVatfzrn5jgk=
 =8la7
 -----END PGP SIGNATURE-----

Merge tag 'efi-next-for-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI updates from Ard Biesheuvel:
 "Only a handful of changes this cycle, consisting of cleanup work and a
  low-prio bugfix:

   - Additional cleanup by Tim for the efivarfs variable name length
     confusion

   - Avoid freeing a bogus pointer when virtual remapping is omitted in
     the EFI boot stub"

* tag 'efi-next-for-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efi: libstub: only free priv.runtime_map when allocated
  efi: Clear up misconceptions about a maximum variable name size
  efivarfs: Remove unused internal struct members
  Documentation: Mark the 'efivars' sysfs interface as removed
  efi: pstore: Request at most 512 bytes for variable names
2024-05-14 15:19:26 -07:00
Masahiro Yamada
7f7f6f7ad6 Makefile: remove redundant tool coverage variables
Now Kbuild provides reasonable defaults for objtool, sanitizers, and
profilers.

Remove redundant variables.

Note:

This commit changes the coverage for some objects:

  - include arch/mips/vdso/vdso-image.o into UBSAN, GCOV, KCOV
  - include arch/sparc/vdso/vdso-image-*.o into UBSAN
  - include arch/sparc/vdso/vma.o into UBSAN
  - include arch/x86/entry/vdso/extable.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
  - include arch/x86/entry/vdso/vdso-image-*.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
  - include arch/x86/entry/vdso/vdso32-setup.o into KASAN, KCSAN, UBSAN, GCOV, KCOV
  - include arch/x86/entry/vdso/vma.o into GCOV, KCOV
  - include arch/x86/um/vdso/vma.o into KASAN, GCOV, KCOV

I believe these are positive effects because all of them are kernel
space objects.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Roberto Sassu <roberto.sassu@huawei.com>
2024-05-14 23:35:48 +09:00
Hagar Hemdan
4b2543f7e1 efi: libstub: only free priv.runtime_map when allocated
priv.runtime_map is only allocated when efi_novamap is not set.
Otherwise, it is an uninitialized value.  In the error path, it is freed
unconditionally.  Avoid passing an uninitialized value to free_pool.
Free priv.runtime_map only when it was allocated.

This bug was discovered and resolved using Coverity Static Analysis
Security Testing (SAST) by Synopsys, Inc.

Fixes: f80d26043a ("efi: libstub: avoid efi_get_memory_map() for allocating the virt map")
Cc: <stable@vger.kernel.org>
Signed-off-by: Hagar Hemdan <hagarhem@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-04-29 17:47:32 +02:00
Ard Biesheuvel
decd347c2a x86/efistub: Reinstate soft limit for initrd loading
Commit

  8117961d98fb2 ("x86/efi: Disregard setup header of loaded image")

dropped the memcopy of the image's setup header into the boot_params
struct provided to the core kernel, on the basis that EFI boot does not
need it and should rely only on a single protocol to interface with the
boot chain. It is also a prerequisite for being able to increase the
section alignment to 4k, which is needed to enable memory protections
when running in the boot services.

So only the setup_header fields that matter to the core kernel are
populated explicitly, and everything else is ignored. One thing was
overlooked, though: the initrd_addr_max field in the setup_header is not
used by the core kernel, but it is used by the EFI stub itself when it
loads the initrd, where its default value of INT_MAX is used as the soft
limit for memory allocation.

This means that, in the old situation, the initrd was virtually always
loaded in the lower 2G of memory, but now, due to initrd_addr_max being
0x0, the initrd may end up anywhere in memory. This should not be an
issue principle, as most systems can deal with this fine. However, it
does appear to tickle some problems in older UEFI implementations, where
the memory ends up being corrupted, resulting in errors when unpacking
the initramfs.

So set the initrd_addr_max field to INT_MAX like it was before.

Fixes: 8117961d98fb2 ("x86/efi: Disregard setup header of loaded image")
Reported-by: Radek Podgorny <radek@podgorny.cz>
Closes: https://lore.kernel.org/all/a99a831a-8ad5-4cb0-bff9-be637311f771@podgorny.cz
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-28 16:19:46 +01:00
Ard Biesheuvel
61d130f261 efi/libstub: Cast away type warning in use of max()
Avoid a type mismatch warning in max() by switching to max_t() and
providing the type explicitly.

Fixes: 3cb4a48275 ("efi/libstub: fix efi_random_alloc() ...")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-28 16:18:57 +01:00
Linus Torvalds
ab8de2dbfc EFI fixes for v6.9 #2
- Fix logic that is supposed to prevent placement of the kernel image
   below LOAD_PHYSICAL_ADDR
 - Use the firmware stack in the EFI stub when running in mixed mode
 - Clear BSS only once when using mixed mode
 - Check efi.get_variable() function pointer for NULL before trying to
   call it
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQQm/3uucuRGn1Dmh0wbglWLn0tXAUCZgCRgwAKCRAwbglWLn0t
 XHozAP9jLdeGs1ReYZAn+W0QtW/SJHJznoPiHcktdNKG4rNX3QD9G3URu0f4jKCG
 yvjw8qHM1pC2cihXXjABjf7gL7g6LAE=
 =cNP7
 -----END PGP SIGNATURE-----

Merge tag 'efi-fixes-for-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI fixes from Ard Biesheuvel:

 - Fix logic that is supposed to prevent placement of the kernel image
   below LOAD_PHYSICAL_ADDR

 - Use the firmware stack in the EFI stub when running in mixed mode

 - Clear BSS only once when using mixed mode

 - Check efi.get_variable() function pointer for NULL before trying to
   call it

* tag 'efi-fixes-for-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efi: fix panic in kdump kernel
  x86/efistub: Don't clear BSS twice in mixed mode
  x86/efistub: Call mixed mode boot services on the firmware's stack
  efi/libstub: fix efi_random_alloc() to allocate memory at alloc_min or higher address
2024-03-24 13:54:06 -07:00
Ard Biesheuvel
df7ecce842 x86/efistub: Don't clear BSS twice in mixed mode
Clearing BSS should only be done once, at the very beginning.
efi_pe_entry() is the entrypoint from the firmware, which may not clear
BSS and so it is done explicitly. However, efi_pe_entry() is also used
as an entrypoint by the mixed mode startup code, in which case BSS will
already have been cleared, and doing it again at this point will corrupt
global variables holding the firmware's GDT/IDT and segment selectors.

So make the memset() conditional on whether the EFI stub is running in
native mode.

Fixes: b3810c5a2c ("x86/efistub: Clear decompressor BSS in native EFI entrypoint")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-24 09:28:33 +01:00
KONDO KAZUMA(近藤 和真)
3cb4a48275 efi/libstub: fix efi_random_alloc() to allocate memory at alloc_min or higher address
Following warning is sometimes observed while booting my servers:
  [    3.594838] DMA: preallocated 4096 KiB GFP_KERNEL pool for atomic allocations
  [    3.602918] swapper/0: page allocation failure: order:10, mode:0xcc1(GFP_KERNEL|GFP_DMA), nodemask=(null),cpuset=/,mems_allowed=0-1
  ...
  [    3.851862] DMA: preallocated 1024 KiB GFP_KERNEL|GFP_DMA pool for atomic allocation

If 'nokaslr' boot option is set, the warning always happens.

On x86, ZONE_DMA is small zone at the first 16MB of physical address
space. When this problem happens, most of that space seems to be used by
decompressed kernel. Thereby, there is not enough space at DMA_ZONE to
meet the request of DMA pool allocation.

The commit 2f77465b05 ("x86/efistub: Avoid placing the kernel below
LOAD_PHYSICAL_ADDR") tried to fix this problem by introducing lower
bound of allocation.

But the fix is not complete.

efi_random_alloc() allocates pages by following steps.
1. Count total available slots ('total_slots')
2. Select a slot ('target_slot') to allocate randomly
3. Calculate a starting address ('target') to be included target_slot
4. Allocate pages, which starting address is 'target'

In step 1, 'alloc_min' is used to offset the starting address of memory
chunk. But in step 3 'alloc_min' is not considered at all.  As the
result, 'target' can be miscalculated and become lower than 'alloc_min'.

When KASLR is disabled, 'target_slot' is always 0 and the problem
happens everytime if the EFI memory map of the system meets the
condition.

Fix this problem by calculating 'target' considering 'alloc_min'.

Cc: linux-efi@vger.kernel.org
Cc: Tom Englund <tomenglund26@gmail.com>
Cc: linux-kernel@vger.kernel.org
Fixes: 2f77465b05 ("x86/efistub: Avoid placing the kernel below LOAD_PHYSICAL_ADDR")
Signed-off-by: Kazuma Kondo <kazuma-kondo@nec.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-22 14:08:42 +01:00
Linus Torvalds
906a93befe EFI fixes for v6.9 #1
- Explicitly wipe BSS in the native EFI entrypoint, so that globals
   shared with the legacy decompressor are zero-initialized correctly.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQQm/3uucuRGn1Dmh0wbglWLn0tXAUCZfamQgAKCRAwbglWLn0t
 XHK9AP9tfaBRi2v3ee5DONWc6cAIg2UUJtZABsWjo6M1HJjQjQD/cKKG3F9jo9L/
 jJ890WGNpDTN8KJJ7GWDA41UQ/zucAI=
 =fIHG
 -----END PGP SIGNATURE-----

Merge tag 'efi-fixes-for-v6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI fix from Ard Biesheuvel:
 "This fixes an oversight on my part in the recent EFI stub rework for
  x86, which is needed to get Linux/x86 distro builds signed again for
  secure boot by Microsoft. For this reason, most of this work is being
  backported to v6.1, which is therefore also affected by this
  regression.

   - Explicitly wipe BSS in the native EFI entrypoint, so that globals
     shared with the legacy decompressor are zero-initialized correctly"

* tag 'efi-fixes-for-v6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  x86/efistub: Clear decompressor BSS in native EFI entrypoint
2024-03-17 12:26:04 -07:00
Ard Biesheuvel
b3810c5a2c x86/efistub: Clear decompressor BSS in native EFI entrypoint
The EFI stub on x86 no longer invokes the decompressor as a subsequent
boot stage, but calls into the decompression code directly while running
in the context of the EFI boot services.

This means that when using the native EFI entrypoint (as opposed to the
EFI handover protocol, which clears BSS explicitly), the firmware PE
image loader is being relied upon to ensure that BSS is zeroed before
the EFI stub is entered from the firmware.

As Radek's report proves, this is a bad idea. Not all loaders do this
correctly, which means some global variables that should be statically
initialized to 0x0 may have junk in them.

So clear BSS explicitly when entering via efi_pe_entry(). Note that
zeroing BSS from C code is not generally safe, but in this case, the
following assignment and dereference of a global pointer variable
ensures that the memset() cannot be deferred or reordered.

Cc: <stable@kernel.org> # v6.1+
Reported-by: Radek Podgorny <radek@podgorny.cz>
Closes: https://lore.kernel.org/all/a99a831a-8ad5-4cb0-bff9-be637311f771@podgorny.cz
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-15 19:47:09 +01:00
Linus Torvalds
e5eb28f6d1 - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
heap optimizations".
 
 - Kuan-Wei Chiu has also sped up the library sorting code in the series
   "lib/sort: Optimize the number of swaps and comparisons".
 
 - Alexey Gladkov has added the ability for code running within an IPC
   namespace to alter its IPC and MQ limits.  The series is "Allow to
   change ipc/mq sysctls inside ipc namespace".
 
 - Geert Uytterhoeven has contributed some dhrystone maintenance work in
   the series "lib: dhry: miscellaneous cleanups".
 
 - Ryusuke Konishi continues nilfs2 maintenance work in the series
 
 	"nilfs2: eliminate kmap and kmap_atomic calls"
 	"nilfs2: fix kernel bug at submit_bh_wbc()"
 
 - Nathan Chancellor has updated our build tools requirements in the
   series "Bump the minimum supported version of LLVM to 13.0.1".
 
 - Muhammad Usama Anjum continues with the selftests maintenance work in
   the series "selftests/mm: Improve run_vmtests.sh".
 
 - Oleg Nesterov has done some maintenance work against the signal code
   in the series "get_signal: minor cleanups and fix".
 
 Plus the usual shower of singleton patches in various parts of the tree.
 Please see the individual changelogs for details.
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZfMnvgAKCRDdBJ7gKXxA
 jjKMAP4/Upq07D4wjkMVPb+QrkipbbLpdcgJ++q3z6rba4zhPQD+M3SFriIJk/Xh
 tKVmvihFxfAhdDthseXcIf1nBjMALwY=
 =8rVc
 -----END PGP SIGNATURE-----

Merge tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:

 - Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
   heap optimizations".

 - Kuan-Wei Chiu has also sped up the library sorting code in the series
   "lib/sort: Optimize the number of swaps and comparisons".

 - Alexey Gladkov has added the ability for code running within an IPC
   namespace to alter its IPC and MQ limits. The series is "Allow to
   change ipc/mq sysctls inside ipc namespace".

 - Geert Uytterhoeven has contributed some dhrystone maintenance work in
   the series "lib: dhry: miscellaneous cleanups".

 - Ryusuke Konishi continues nilfs2 maintenance work in the series

	"nilfs2: eliminate kmap and kmap_atomic calls"
	"nilfs2: fix kernel bug at submit_bh_wbc()"

 - Nathan Chancellor has updated our build tools requirements in the
   series "Bump the minimum supported version of LLVM to 13.0.1".

 - Muhammad Usama Anjum continues with the selftests maintenance work in
   the series "selftests/mm: Improve run_vmtests.sh".

 - Oleg Nesterov has done some maintenance work against the signal code
   in the series "get_signal: minor cleanups and fix".

Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.

* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
  nilfs2: prevent kernel bug at submit_bh_wbc()
  nilfs2: fix failure to detect DAT corruption in btree and direct mappings
  ocfs2: enable ocfs2_listxattr for special files
  ocfs2: remove SLAB_MEM_SPREAD flag usage
  assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
  buildid: use kmap_local_page()
  watchdog/core: remove sysctl handlers from public header
  nilfs2: use div64_ul() instead of do_div()
  mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
  kexec: copy only happens before uchunk goes to zero
  get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
  get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
  get_signal: don't abuse ksig->info.si_signo and ksig->sig
  const_structs.checkpatch: add device_type
  Normalise "name (ad@dr)" MODULE_AUTHORs to "name <ad@dr>"
  dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
  list: leverage list_is_head() for list_entry_is_head()
  nilfs2: MAINTAINERS: drop unreachable project mirror site
  smp: make __smp_processor_id() 0-argument macro
  fat: fix uninitialized field in nostale filehandles
  ...
2024-03-14 18:03:09 -07:00
Linus Torvalds
70ef654469 EFI updates for v6.9:
- Measure initrd and command line using the CC protocol if the ordinary
   TCG2 protocol is not implemented, typically on TDX confidential VMs
 
 - Avoid creating mappings that are both writable and executable while
   running in the EFI boot services. This is a prerequisite for getting
   the x86 shim loader signed by MicroSoft again, which allows the
   distros to install on x86 PCs that ship with EFI secure boot enabled.
 
 - API update for struct platform_driver::remove()
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQQm/3uucuRGn1Dmh0wbglWLn0tXAUCZe9ZfQAKCRAwbglWLn0t
 XKA3AQCLEZB8cFifk0pIItUCbSLfplJsS926AgknvwLYSRn8WAEA/WHZ+42TTiPy
 w2U8zmhaqzmqWtwrwjjMUmoap90KYwA=
 =4NVe
 -----END PGP SIGNATURE-----

Merge tag 'efi-next-for-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi

Pull EFI updates from Ard Biesheuvel:

 - Measure initrd and command line using the CC protocol if the ordinary
   TCG2 protocol is not implemented, typically on TDX confidential VMs

 - Avoid creating mappings that are both writable and executable while
   running in the EFI boot services. This is a prerequisite for getting
   the x86 shim loader signed by MicroSoft again, which allows the
   distros to install on x86 PCs that ship with EFI secure boot enabled.

 - API update for struct platform_driver::remove()

* tag 'efi-next-for-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  virt: efi_secret: Convert to platform remove callback returning void
  x86/efistub: Remap kernel text read-only before dropping NX attribute
  efi/libstub: Add get_event_log() support for CC platforms
  efi/libstub: Measure into CC protocol if TCG2 protocol is absent
  efi/libstub: Add Confidential Computing (CC) measurement typedefs
  efi/tpm: Use symbolic GUID name from spec for final events table
  efi/libstub: Use TPM event typedefs from the TCG PC Client spec
2024-03-13 12:37:41 -07:00
Ard Biesheuvel
9c55461040 x86/efistub: Remap kernel text read-only before dropping NX attribute
Currently, the EFI stub invokes the EFI memory attributes protocol to
strip any NX restrictions from the entire loaded kernel, resulting in
all code and data being mapped read-write-execute.

The point of the EFI memory attributes protocol is to remove the need
for all memory allocations to be mapped with both write and execute
permissions by default, and make it the OS loader's responsibility to
transition data mappings to code mappings where appropriate.

Even though the UEFI specification does not appear to leave room for
denying memory attribute changes based on security policy, let's be
cautious and avoid relying on the ability to create read-write-execute
mappings. This is trivially achievable, given that the amount of kernel
code executing via the firmware's 1:1 mapping is rather small and
limited to the .head.text region. So let's drop the NX restrictions only
on that subregion, but not before remapping it as read-only first.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-09 11:37:18 +01:00
Kuppuswamy Sathyanarayanan
d228814b19 efi/libstub: Add get_event_log() support for CC platforms
To allow event log info access after boot, EFI boot stub extracts
the event log information and installs it in an EFI configuration
table. Currently, EFI boot stub only supports installation of event
log only for TPM 1.2 and TPM 2.0 protocols. Extend the same support
for CC protocol. Since CC platform also uses TCG2 format, reuse TPM2
support code as much as possible.

Link: https://uefi.org/specs/UEFI/2.10/38_Confidential_Computing.html#efi-cc-measurement-protocol [1]
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Link: https://lkml.kernel.org/r/0229a87e-fb19-4dad-99fc-4afd7ed4099a%40collabora.com
[ardb: Split out final events table handling to avoid version confusion]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-09 11:37:17 +01:00
Ard Biesheuvel
ac93cbfc2a efi/libstub: Measure into CC protocol if TCG2 protocol is absent
To accommodate confidential compute VMs that expose the simplified CC
measurement protocol instead of the full-blown TCG2 one, fall back to
the former if the latter does not exist.

The CC protocol was designed to be used in this manner, which is why the
types and prototypes have been kept the same where possible. So reuse
the existing code, and only deviate from the TCG2 code path where
needed.

Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-09 11:37:15 +01:00
Kuppuswamy Sathyanarayanan
0bbe5b0ea9 efi/libstub: Add Confidential Computing (CC) measurement typedefs
If the virtual firmware implements TPM support, TCG2 protocol will be
used for kernel measurements and event logging support. But in CC
environment, not all platforms support or enable the TPM feature. UEFI
specification [1] exposes protocol and interfaces used for kernel
measurements in CC platforms without TPM support.

More details about the EFI CC measurements and logging can be found
in [1].

Link: https://uefi.org/specs/UEFI/2.10/38_Confidential_Computing.html#efi-cc-measurement-protocol [1]
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
[ardb: Drop code changes, keep typedefs and #define's only]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-09 11:36:56 +01:00
Ard Biesheuvel
7a1381e831 efi/tpm: Use symbolic GUID name from spec for final events table
The LINUX_EFI_ GUID identifiers are only intended to be used to refer to
GUIDs that are part of the Linux implementation, and are not considered
external ABI. (Famous last words).

GUIDs that already have a symbolic name in the spec should use that
name, to avoid confusion between firmware components. So use the
official name EFI_TCG2_FINAL_EVENTS_TABLE_GUID for the TCG2 'final
events' configuration table.

Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-09 11:36:56 +01:00
Ard Biesheuvel
3e0b0f880e efi/libstub: Use TPM event typedefs from the TCG PC Client spec
Our efi_tcg2_tagged_event is not defined in the EFI spec, but it is not
a local invention either: it was taken from the TCG PC Client spec,
where it is called TCG_PCClientTaggedEvent.

Note that this spec also contains some guidance on how to populate it,
which is not being followed closely at the moment; it claims that the
event size should cover the TCG_PCClientTaggedEvent and its payload
only, but it currently covers the preceding efi_tcg2_event too.

However, this directly contradicts the TCG EFI protocol specification,
which states very clearly that the event size should cover the entire
data structure, including the leading efi_tcg2_event_t struct.

So rename the struct and document its provenance, but retain the
existing logic to populate the size field.

Link: https://lore.kernel.org/all/20240308085754.476197-8-ardb+git@google.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-03-09 11:36:54 +01:00
Ard Biesheuvel
cd0d9d92c8 x86/boot: Move mem_encrypt= parsing to the decompressor
The early SME/SEV code parses the command line very early, in order to
decide whether or not memory encryption should be enabled, which needs
to occur even before the initial page tables are created.

This is problematic for a number of reasons:
- this early code runs from the 1:1 mapping provided by the decompressor
  or firmware, which uses a different translation than the one assumed by
  the linker, and so the code needs to be built in a special way;
- parsing external input while the entire kernel image is still mapped
  writable is a bad idea in general, and really does not belong in
  security minded code;
- the current code ignores the built-in command line entirely (although
  this appears to be the case for the entire decompressor)

Given that the decompressor/EFI stub is an intrinsic part of the x86
bootable kernel image, move the command line parsing there and out of
the core kernel. This removes the need to build lib/cmdline.o in a
special way, or to use RIP-relative LEA instructions in inline asm
blocks.

This involves a new xloadflag in the setup header to indicate
that mem_encrypt=on appeared on the kernel command line.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240227151907.387873-17-ardb+git@google.com
2024-03-04 18:12:28 +01:00
Ard Biesheuvel
7205f06e84 efi/libstub: Add generic support for parsing mem_encrypt=
Parse the mem_encrypt= command line parameter from the EFI stub if
CONFIG_ARCH_HAS_MEM_ENCRYPT=y, so that it can be passed to the early
boot code by the arch code in the stub.

This avoids the need for the core kernel to do any string parsing very
early in the boot.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240227151907.387873-16-ardb+git@google.com
2024-03-04 18:12:24 +01:00
Nathan Chancellor
2947a4567f treewide: update LLVM Bugzilla links
LLVM moved their issue tracker from their own Bugzilla instance to GitHub
issues.  While all of the links are still valid, they may not necessarily
show the most up to date information around the issues, as all updates
will occur on GitHub, not Bugzilla.

Another complication is that the Bugzilla issue number is not always the
same as the GitHub issue number.  Thankfully, LLVM maintains this mapping
through two shortlinks:

  https://llvm.org/bz<num> -> https://bugs.llvm.org/show_bug.cgi?id=<num>
  https://llvm.org/pr<num> -> https://github.com/llvm/llvm-project/issues/<mapped_num>

Switch all "https://bugs.llvm.org/show_bug.cgi?id=<num>" links to the
"https://llvm.org/pr<num>" shortlink so that the links show the most up to
date information.  Each migrated issue links back to the Bugzilla entry,
so there should be no loss of fidelity of information here.

Link: https://lkml.kernel.org/r/20240109-update-llvm-links-v1-3-eb09b59db071@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Fangrui Song <maskray@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:38:51 -08:00
Yang Li
aa0e784dea efi/libstub: Add one kernel-doc comment
Add the description of @memory_type to silence the warning:
drivers/firmware/efi/libstub/alignedmem.c:27: warning: Function parameter or struct member 'memory_type' not described in 'efi_allocate_pages_aligned'

Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
[ardb: tweak comment]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-01-30 21:44:21 +01:00
Ard Biesheuvel
2f77465b05 x86/efistub: Avoid placing the kernel below LOAD_PHYSICAL_ADDR
The EFI stub's kernel placement logic randomizes the physical placement
of the kernel by taking all available memory into account, and picking a
region at random, based on a random seed.

When KASLR is disabled, this seed is set to 0x0, and this results in the
lowest available region of memory to be selected for loading the kernel,
even if this is below LOAD_PHYSICAL_ADDR. Some of this memory is
typically reserved for the GFP_DMA region, to accommodate masters that
can only access the first 16 MiB of system memory.

Even if such devices are rare these days, we may still end up with a
warning in the kernel log, as reported by Tom:

 swapper/0: page allocation failure: order:10, mode:0xcc1(GFP_KERNEL|GFP_DMA), nodemask=(null),cpuset=/,mems_allowed=0

Fix this by tweaking the random allocation logic to accept a low bound
on the placement, and set it to LOAD_PHYSICAL_ADDR.

Fixes: a1b87d54f4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot")
Reported-by: Tom Englund <tomenglund26@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218404
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-01-30 21:44:21 +01:00
Ard Biesheuvel
a7a6a01f88 x86/efistub: Give up if memory attribute protocol returns an error
The recently introduced EFI memory attributes protocol should be used
if it exists to ensure that the memory allocation created for the kernel
permits execution. This is needed for compatibility with tightened
requirements related to Windows logo certification for x86 PCs.

Currently, we simply strip the execute protect (XP) attribute from the
entire range, but this might be rejected under some firmware security
policies, and so in a subsequent patch, this will be changed to only
strip XP from the executable region that runs early, and make it
read-only (RO) as well.

In order to catch any issues early, ensure that the memory attribute
protocol works as intended, and give up if it produces spurious errors.

Note that the DXE services based fallback was always based on best
effort, so don't propagate any errors returned by that API.

Fixes: a1b87d54f4 ("x86/efistub: Avoid legacy decompressor when doing EFI boot")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-01-26 16:58:19 +01:00
Ard Biesheuvel
d2baf8cc82 riscv/efistub: Tighten ELF relocation check
The EFI stub makefile contains logic to ensure that the objects that
make up the stub do not contain relocations that require runtime fixups
(typically to account for the runtime load address of the executable)

On RISC-V, we also avoid GP based relocations, as they require that GP
is assigned the correct base in the startup code, which is not
implemented in the EFI stub.

So add these relocation types to the grep expression that is used to
carry out this check.

Link: https://lkml.kernel.org/r/42c63cb9-87d0-49db-9af8-95771b186684%40siemens.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-01-23 14:31:33 +01:00