The patch titled
Subject: kasan: add compiler barriers to KUNIT_EXPECT_KASAN_FAIL
has been added to the -mm tree. Its filename is
kasan-add-compiler-barriers-to-kunit_expect_kasan_fail.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/kasan-add-compiler-barriers-to-kunit_expect_kasan_fail.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/kasan-add-compiler-barriers-to-kunit_expect_kasan_fail.patch
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------------------------------------------------------
From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Subject: kasan: add compiler barriers to KUNIT_EXPECT_KASAN_FAIL
It might not be obvious to the compiler that the expression must be
executed between writing and reading to fail_data. In this case, the
compiler might reorder or optimize away some of the accesses, and
the tests will fail.
Add compiler barriers around the expression in KUNIT_EXPECT_KASAN_FAIL.
Link: https://lkml.kernel.org/r/a37dab02f89ad93cc986a87866da74fb8be1850d.1609871239.git.andreyknvl@xxxxxxxxxx
Link: https://linux-review.googlesource.com/id/I046079f48641a1d36fe627fc8827a9249102fd50Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: Branislav Rankov <Branislav.Rankov@xxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Evgenii Stepanov <eugenis@xxxxxxxxxx>
Cc: Kevin Brodsky <kevin.brodsky@xxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/test_kasan.c | 2 ++
1 file changed, 2 insertions(+)
--- a/lib/test_kasan.c~kasan-add-compiler-barriers-to-kunit_expect_kasan_fail
+++ a/lib/test_kasan.c
@@ -79,7 +79,9 @@ static void kasan_test_exit(struct kunit
NULL, \
&resource, \
"kasan_data", &fail_data); \
+ barrier(); \
expression; \
+ barrier(); \
KUNIT_EXPECT_EQ(test, \
fail_data.report_expected, \
fail_data.report_found); \
_
Patches currently in -mm which might be from andreyknvl@xxxxxxxxxx are
kasan-prefix-exported-functions-with-kasan_.patch
kasan-clarify-hw_tags-impact-on-tbi.patch
kasan-clean-up-comments-in-tests.patch
kasan-add-match-all-tag-tests.patch
kasan-arm64-allow-using-kunit-tests-with-hw_tags-mode.patch
kasan-rename-config_test_kasan_module.patch
kasan-add-compiler-barriers-to-kunit_expect_kasan_fail.patch
kasan-adopt-kmalloc_uaf2-test-to-hw_tags-mode.patch
kasan-fix-memory-corruption-in-kasan_bitops_tags-test.patch
kasan-fix-bug-detection-via-ksize-for-hw_tags-mode.patch
kasan-add-proper-page-allocator-tests.patch
