From: Greg Kroah-Hartman <[email protected]> From: Andrey Konovalov <[email protected]>
[ Upstream commit e66e1799a76621003e5b04c9c057826a2152e103 ] Since the hardware tag-based KASAN mode might not have a redzone that comes after an allocated object (when kasan.mode=prod is enabled), the kasan_bitops_tags() test ends up corrupting the next object in memory. Change the test so it always accesses the redzone that lies within the allocated object's boundaries. Link: https://linux-review.googlesource.com/id/I67f51d1ee48f0a8d0fe2658c2a39e4879fe0832a Link: https://lkml.kernel.org/r/7d452ce4ae35bb1988d2c9244dfea56cf2cc9315.1610733117.git.andreyk...@google.com Signed-off-by: Andrey Konovalov <[email protected]> Reviewed-by: Marco Elver <[email protected]> Reviewed-by: Alexander Potapenko <[email protected]> Cc: Andrey Ryabinin <[email protected]> Cc: Branislav Rankov <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Evgenii Stepanov <[email protected]> Cc: Kevin Brodsky <[email protected]> Cc: Peter Collingbourne <[email protected]> Cc: Vincenzo Frascino <[email protected]> Cc: Will Deacon <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- lib/test_kasan.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/lib/test_kasan.c b/lib/test_kasan.c index 2947274cc2d3..5a2f104ca13f 100644 --- a/lib/test_kasan.c +++ b/lib/test_kasan.c @@ -737,13 +737,13 @@ static void kasan_bitops_tags(struct kunit *test) return; } - /* Allocation size will be rounded to up granule size, which is 16. */ - bits = kzalloc(sizeof(*bits), GFP_KERNEL); + /* kmalloc-64 cache will be used and the last 16 bytes will be the redzone. */ + bits = kzalloc(48, GFP_KERNEL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bits); - /* Do the accesses past the 16 allocated bytes. */ - kasan_bitops_modify(test, BITS_PER_LONG, &bits[1]); - kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, &bits[1]); + /* Do the accesses past the 48 allocated bytes, but within the redone. */ + kasan_bitops_modify(test, BITS_PER_LONG, (void *)bits + 48); + kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, (void *)bits + 48); kfree(bits); } -- 2.30.1
