diff options
| author | Jann Horn <jannh@google.com> | 2025-07-28 22:11:54 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-08-05 13:28:46 -0700 |
| commit | 475356fe2814f2f0b188da8bf0f1fcc579d81272 (patch) | |
| tree | 5f18542afd0279d54c88a8505c6dccac906ede31 | |
| parent | 6bcdbd62bd56e6d7383f9e06d9d148935b3c9b73 (diff) | |
kasan/test: fix protection against compiler elision
The kunit test is using assignments to
"static volatile void *kasan_ptr_result" to prevent elision of memory
loads, but that's not working:
In this variable definition, the "volatile" applies to the "void", not to
the pointer.
To make "volatile" apply to the pointer as intended, it must follow
after the "*".
This makes the kasan_memchr test pass again on my system. The
kasan_strings test is still failing because all the definitions of
load_unaligned_zeropad() are lacking explicit instrumentation hooks and
ASAN does not instrument asm() memory operands.
Link: https://lkml.kernel.org/r/20250728-kasan-kunit-fix-volatile-v1-1-e7157c9af82d@google.com
Fixes: 5f1c8108e7ad ("mm:kasan: fix sparse warnings: Should it be static?")
Signed-off-by: Jann Horn <jannh@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Nihar Chaithanya <niharchaithanya@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/kasan/kasan_test_c.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/kasan/kasan_test_c.c b/mm/kasan/kasan_test_c.c index 2aa12dfa427a..e0968acc03aa 100644 --- a/mm/kasan/kasan_test_c.c +++ b/mm/kasan/kasan_test_c.c @@ -47,7 +47,7 @@ static struct { * Some tests use these global variables to store return values from function * calls that could otherwise be eliminated by the compiler as dead code. */ -static volatile void *kasan_ptr_result; +static void *volatile kasan_ptr_result; static volatile int kasan_int_result; /* Probe for console output: obtains test_status lines of interest. */ |