kasan, arm64: tests supports for HW_TAGS async mode

This change adds KASAN-KUnit tests support for the async HW_TAGS mode.

In async mode, tag fault aren't being generated synchronously when a
bad access happens, but are instead explicitly checked for by the kernel.

As each KASAN-KUnit test expect a fault to happen before the test is over,
check for faults as a part of the test handler.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20210315132019.33202-10-vincenzo.frascino@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Andrey Konovalov 2021-03-15 13:20:19 +00:00 committed by Catalin Marinas
parent eab0e6e17d
commit e80a76aa1a
5 changed files with 29 additions and 6 deletions

View file

@ -69,10 +69,10 @@ static void kasan_test_exit(struct kunit *test)
* resource named "kasan_data". Do not use this name for KUnit resources
* outside of KASAN tests.
*
* For hardware tag-based KASAN, when a tag fault happens, tag checking is
* normally auto-disabled. When this happens, this test handler reenables
* tag checking. As tag checking can be only disabled or enabled per CPU, this
* handler disables migration (preemption).
* For hardware tag-based KASAN in sync mode, when a tag fault happens, tag
* checking is auto-disabled. When this happens, this test handler reenables
* tag checking. As tag checking can be only disabled or enabled per CPU,
* this handler disables migration (preemption).
*
* Since the compiler doesn't see that the expression can change the fail_data
* fields, it can reorder or optimize away the accesses to those fields.
@ -80,7 +80,8 @@ static void kasan_test_exit(struct kunit *test)
* expression to prevent that.
*/
#define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \
if (IS_ENABLED(CONFIG_KASAN_HW_TAGS)) \
if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \
!kasan_async_mode_enabled()) \
migrate_disable(); \
WRITE_ONCE(fail_data.report_expected, true); \
WRITE_ONCE(fail_data.report_found, false); \
@ -92,10 +93,14 @@ static void kasan_test_exit(struct kunit *test)
barrier(); \
expression; \
barrier(); \
if (kasan_async_mode_enabled()) \
kasan_force_async_fault(); \
barrier(); \
KUNIT_EXPECT_EQ(test, \
READ_ONCE(fail_data.report_expected), \
READ_ONCE(fail_data.report_found)); \
if (IS_ENABLED(CONFIG_KASAN_HW_TAGS)) { \
if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \
!kasan_async_mode_enabled()) { \
if (READ_ONCE(fail_data.report_found)) \
kasan_enable_tagging_sync(); \
migrate_enable(); \