The patch titled Subject: kasan: fix KASAN_STACK dependency for HW_TAGS has been removed from the -mm tree. Its filename was kasan-fix-kasan_stack-dependency-for-hw_tags.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------ From: Andrey Konovalov andreyknvl@google.com Subject: kasan: fix KASAN_STACK dependency for HW_TAGS

There's a runtime failure when running HW_TAGS-enabled kernel built with GCC on hardware that doesn't support MTE. GCC-built kernels always have CONFIG_KASAN_STACK enabled, even though stack instrumentation isn't supported by HW_TAGS. Having that config enabled causes KASAN to issue MTE-only instructions to unpoison kernel stacks, which causes the failure.

Fix the issue by disallowing CONFIG_KASAN_STACK when HW_TAGS is used.

(The commit that introduced CONFIG_KASAN_HW_TAGS specified proper dependency for CONFIG_KASAN_STACK_ENABLE but not for CONFIG_KASAN_STACK.)

Link: https://lkml.kernel.org/r/59e75426241dbb5611277758c8d4d6f5f9298dac.161521544... Fixes: 6a63a63ff1ac ("kasan: introduce CONFIG_KASAN_HW_TAGS") Signed-off-by: Andrey Konovalov andreyknvl@google.com Reported-by: Catalin Marinas catalin.marinas@arm.com Cc: stable@vger.kernel.org Cc: Will Deacon will.deacon@arm.com Cc: Vincenzo Frascino vincenzo.frascino@arm.com Cc: Dmitry Vyukov dvyukov@google.com Cc: Andrey Ryabinin aryabinin@virtuozzo.com Cc: Alexander Potapenko glider@google.com Cc: Marco Elver elver@google.com Cc: Peter Collingbourne pcc@google.com Cc: Evgenii Stepanov eugenis@google.com Cc: Branislav Rankov Branislav.Rankov@arm.com Cc: Kevin Brodsky kevin.brodsky@arm.com Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

lib/Kconfig.kasan | 1 + 1 file changed, 1 insertion(+)

--- a/lib/Kconfig.kasan~kasan-fix-kasan_stack-dependency-for-hw_tags +++ a/lib/Kconfig.kasan @@ -156,6 +156,7 @@ config KASAN_STACK_ENABLE

config KASAN_STACK int + depends on KASAN_GENERIC || KASAN_SW_TAGS default 1 if KASAN_STACK_ENABLE || CC_IS_GCC default 0

_

Patches currently in -mm which might be from andreyknvl@google.com are

kasan-fix-per-page-tags-for-non-page_alloc-pages.patch kasan-initialize-shadow-to-tag_invalid-for-sw_tags.patch mm-kasan-dont-poison-boot-memory-with-tag-based-modes.patch arm64-kasan-allow-to-init-memory-when-setting-tags.patch kasan-init-memory-in-kasan_unpoison-for-hw_tags.patch kasan-mm-integrate-page_alloc-init-with-hw_tags.patch kasan-mm-integrate-slab-init_on_alloc-with-hw_tags.patch kasan-mm-integrate-slab-init_on_free-with-hw_tags.patch kasan-docs-clean-up-sections.patch kasan-docs-update-overview-section.patch kasan-docs-update-usage-section.patch kasan-docs-update-error-reports-section.patch kasan-docs-update-boot-parameters-section.patch kasan-docs-update-generic-implementation-details-section.patch kasan-docs-update-sw_tags-implementation-details-section.patch kasan-docs-update-hw_tags-implementation-details-section.patch kasan-docs-update-shadow-memory-section.patch kasan-docs-update-ignoring-accesses-section.patch kasan-docs-update-tests-section.patch