This is a note to let you know that I've just added the patch titled
kasan: fix KASAN_STACK dependency for HW_TAGS
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kasan-fix-kasan_stack-dependency-for-hw_tags.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From d9b571c885a8974fbb7d4ee639dbc643fd000f9e Mon Sep 17 00:00:00 2001
From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Date: Fri, 12 Mar 2021 21:08:13 -0800
Subject: kasan: fix KASAN_STACK dependency for HW_TAGS
From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
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.andreyknvl@xxxxxxxxxx
Fixes: 6a63a63ff1ac ("kasan: introduce CONFIG_KASAN_HW_TAGS")
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Reported-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Cc: Peter Collingbourne <pcc@xxxxxxxxxx>
Cc: Evgenii Stepanov <eugenis@xxxxxxxxxx>
Cc: Branislav Rankov <Branislav.Rankov@xxxxxxx>
Cc: Kevin Brodsky <kevin.brodsky@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
Patches currently in stable-queue which might be from andreyknvl@xxxxxxxxxx are
queue-5.11/kasan-mm-fix-crash-with-hw_tags-and-debug_pagealloc.patch
queue-5.11/kasan-fix-memory-corruption-in-kasan_bitops_tags-tes.patch
queue-5.11/kasan-fix-kasan_stack-dependency-for-hw_tags.patch
queue-5.11/arm64-kasan-fix-page_alloc-tagging-with-debug_virtual.patch
