From d6e5040bd8e53371fafd7e0c7c63b090b3a675db Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Mon, 26 Sep 2022 20:08:47 +0200 Subject: [PATCH] kasan: fix array-bounds warnings in tests GCC's -Warray-bounds option detects out-of-bounds accesses to statically-sized allocations in krealloc out-of-bounds tests. Use OPTIMIZER_HIDE_VAR to suppress the warning. Also change kmalloc_memmove_invalid_size to use OPTIMIZER_HIDE_VAR instead of a volatile variable. Link: https://lkml.kernel.org/r/e94399242d32e00bba6fd0d9ec4c897f188128e8.1664215688.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reported-by: kernel test robot Reviewed-by: Kees Cook Cc: Alexander Potapenko Cc: Andrey Ryabinin Cc: Dmitry Vyukov Cc: Marco Elver Signed-off-by: Andrew Morton --- mm/kasan/kasan_test.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/mm/kasan/kasan_test.c b/mm/kasan/kasan_test.c index f25692d..57e4c72 100644 --- a/mm/kasan/kasan_test.c +++ b/mm/kasan/kasan_test.c @@ -295,6 +295,9 @@ static void krealloc_more_oob_helper(struct kunit *test, ptr2 = krealloc(ptr1, size2, GFP_KERNEL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); + /* Suppress -Warray-bounds warnings. */ + OPTIMIZER_HIDE_VAR(ptr2); + /* All offsets up to size2 must be accessible. */ ptr2[size1 - 1] = 'x'; ptr2[size1] = 'x'; @@ -327,6 +330,9 @@ static void krealloc_less_oob_helper(struct kunit *test, ptr2 = krealloc(ptr1, size2, GFP_KERNEL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); + /* Suppress -Warray-bounds warnings. */ + OPTIMIZER_HIDE_VAR(ptr2); + /* Must be accessible for all modes. */ ptr2[size2 - 1] = 'x'; @@ -540,13 +546,14 @@ static void kmalloc_memmove_invalid_size(struct kunit *test) { char *ptr; size_t size = 64; - volatile size_t invalid_size = size; + size_t invalid_size = size; ptr = kmalloc(size, GFP_KERNEL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); memset((char *)ptr, 0, 64); OPTIMIZER_HIDE_VAR(ptr); + OPTIMIZER_HIDE_VAR(invalid_size); KUNIT_EXPECT_KASAN_FAIL(test, memmove((char *)ptr, (char *)ptr + 4, invalid_size)); kfree(ptr); -- 2.7.4