[PATCH v2 00/14] stackleak: Support Clang stack depth tracking

Kees Cook
2025-05-23T04:39:38Z

v2:
- rename stackleak to kstack_erase (mingo)
- address __init vs inline with KCOV changes
v1: https://lore.kernel.org/lkml/20250507180852.work.231-kees@kernel.org/
RFC: https://lore.kernel.org/lkml/20250502185834.work.560-kees@kernel.org/

Hi,

As part of looking at what GCC plugins could be replaced with Clang
implementations, this series uses the recently landed stack depth tracking
callback in Clang[1] to implement the stackleak feature. Since the Clang
feature is now landed, I'm moving this out of RFC to a v1.

Since this touches a lot of arch-specific Makefiles, I tried to trim
the CC list down to just mailing lists in those cases, otherwise the CC
was giant.

Thanks!

-Kees

[1] https://clang.llvm.org/docs/SanitizerCoverage.html#tracing-stack-depth

Kees Cook (14):
stackleak: Rename STACKLEAK to KSTACK_ERASE
stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth
stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS
x86: Handle KCOV __init vs inline mismatches
arm: Handle KCOV __init vs inline mismatches
arm64: Handle KCOV __init vs inline mismatches
s390: Handle KCOV __init vs inline mismatches
powerpc: Handle KCOV __init vs inline mismatches
mips: Handle KCOV __init vs inline mismatches
loongarch: Handle KCOV __init vs inline mismatches
init.h: Disable sanitizer coverage for __init and __head
kstack_erase: Support Clang stack depth tracking
configs/hardening: Enable CONFIG_KSTACK_ERASE
configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON

arch/Kconfig | 4 +-
arch/arm/Kconfig | 2 +-
arch/arm64/Kconfig | 2 +-
arch/riscv/Kconfig | 2 +-
arch/s390/Kconfig | 2 +-
arch/x86/Kconfig | 2 +-
security/Kconfig.hardening | 45 +++++++++-------
Makefile | 1 +
arch/arm/boot/compressed/Makefile | 2 +-
arch/arm/vdso/Makefile | 2 +-
arch/arm64/kernel/pi/Makefile | 2 +-
arch/arm64/kernel/vdso/Makefile | 3 +-
arch/arm64/kvm/hyp/nvhe/Makefile | 2 +-
arch/riscv/kernel/pi/Makefile | 2 +-
arch/riscv/purgatory/Makefile | 2 +-
arch/sparc/vdso/Makefile | 3 +-
arch/x86/entry/vdso/Makefile | 3 +-
arch/x86/purgatory/Makefile | 2 +-
drivers/firmware/efi/libstub/Makefile | 8 +--
drivers/misc/lkdtm/Makefile | 2 +-
kernel/Makefile | 10 ++--
lib/Makefile | 2 +-
scripts/Makefile.gcc-plugins | 16 +-----
scripts/Makefile.kstack_erase | 21 ++++++++
scripts/gcc-plugins/stackleak_plugin.c | 52 +++++++++----------
Documentation/admin-guide/sysctl/kernel.rst | 4 +-
Documentation/arch/x86/x86_64/mm.rst | 2 +-
Documentation/security/self-protection.rst | 2 +-
.../zh_CN/security/self-protection.rst | 2 +-
arch/arm64/include/asm/acpi.h | 2 +-
arch/loongarch/include/asm/smp.h | 2 +-
arch/mips/include/asm/time.h | 2 +-
arch/s390/hypfs/hypfs.h | 2 +-
arch/s390/hypfs/hypfs_diag.h | 2 +-
arch/x86/entry/calling.h | 4 +-
arch/x86/include/asm/acpi.h | 4 +-
arch/x86/include/asm/init.h | 2 +-
arch/x86/include/asm/realmode.h | 2 +-
include/linux/acpi.h | 4 +-
include/linux/bootconfig.h | 2 +-
include/linux/efi.h | 2 +-
include/linux/init.h | 4 +-
include/linux/{stackleak.h => kstack_erase.h} | 20 +++----
include/linux/memblock.h | 2 +-
include/linux/mfd/dbx500-prcmu.h | 2 +-
include/linux/sched.h | 4 +-
arch/arm/kernel/entry-common.S | 2 +-
arch/arm64/kernel/entry.S | 2 +-
arch/riscv/kernel/entry.S | 2 +-
arch/s390/kernel/entry.S | 2 +-
arch/arm/mm/cache-feroceon-l2.c | 2 +-
arch/arm/mm/cache-tauros2.c | 2 +-
arch/loongarch/kernel/time.c | 2 +-
arch/loongarch/mm/ioremap.c | 4 +-
arch/powerpc/mm/book3s64/hash_utils.c | 2 +-
arch/powerpc/mm/book3s64/radix_pgtable.c | 2 +-
arch/s390/mm/init.c | 2 +-
arch/x86/kernel/kvm.c | 2 +-
drivers/clocksource/timer-orion.c | 2 +-
.../lkdtm/{stackleak.c => kstack_erase.c} | 26 +++++-----
drivers/platform/x86/thinkpad_acpi.c | 4 +-
drivers/soc/ti/pm33xx.c | 2 +-
fs/proc/base.c | 6 +--
kernel/fork.c | 2 +-
kernel/{stackleak.c => kstack_erase.c} | 22 ++++----
tools/objtool/check.c | 4 +-
tools/testing/selftests/lkdtm/config | 2 +-
MAINTAINERS | 6 ++-
kernel/configs/hardening.config | 6 +++
69 files changed, 203 insertions(+), 171 deletions(-)
create mode 100644 scripts/Makefile.kstack_erase
rename include/linux/{stackleak.h => kstack_erase.h} (81%)
rename drivers/misc/lkdtm/{stackleak.c => kstack_erase.c} (89%)
rename kernel/{stackleak.c => kstack_erase.c} (87%)

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2.34.1