From: Greg Kroah-Hartman <gre...@linuxfoundation.org> From: Andrey Konovalov <andreyk...@google.com>
commit d9b571c885a8974fbb7d4ee639dbc643fd000f9e upstream. 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.1615215441.git.andreyk...@google.com Fixes: 6a63a63ff1ac ("kasan: introduce CONFIG_KASAN_HW_TAGS") Signed-off-by: Andrey Konovalov <andreyk...@google.com> Reported-by: Catalin Marinas <catalin.mari...@arm.com> Cc: <sta...@vger.kernel.org> Cc: Will Deacon <will.dea...@arm.com> Cc: Vincenzo Frascino <vincenzo.frasc...@arm.com> Cc: Dmitry Vyukov <dvyu...@google.com> Cc: Andrey Ryabinin <aryabi...@virtuozzo.com> Cc: Alexander Potapenko <gli...@google.com> Cc: Marco Elver <el...@google.com> Cc: Peter Collingbourne <p...@google.com> Cc: Evgenii Stepanov <euge...@google.com> Cc: Branislav Rankov <branislav.ran...@arm.com> Cc: Kevin Brodsky <kevin.brod...@arm.com> Signed-off-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Linus Torvalds <torva...@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- lib/Kconfig.kasan | 1 + 1 file changed, 1 insertion(+) --- a/lib/Kconfig.kasan +++ b/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
