Commit 2b79cb3e authored by Yeoreum Yun's avatar Yeoreum Yun Committed by Andrew Morton
Browse files

kasan: apply write-only mode in kasan kunit testcases 

When KASAN is configured in write-only mode, fetch/load operations do not
trigger tag check faults.

As a result, the outcome of some test cases may differ compared to when
KASAN is configured without write-only mode.

Therefore, by modifying pre-exist testcases check the write only makes tag
check fault (TCF) where writing is perform in "allocated memory" but tag
is invalid (i.e) redzone write in atomic_set() testcases.  Otherwise check
the invalid fetch/read doesn't generate TCF.

Also, skip some testcases affected by initial value (i.e) atomic_cmpxchg()
testcase maybe successd if it passes valid atomic_t address and invalid
oldaval address.  In this case, if invalid atomic_t doesn't have the same
oldval, it won't trigger write operation so the test will pass.

Link: https://lkml.kernel.org/r/20250916222755.466009-3-yeoreum.yun@arm.com


Signed-off-by: default avatarYeoreum Yun <yeoreum.yun@arm.com>
Reviewed-by: default avatarAndrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: default avatarAndrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Breno Leitao <leitao@debian.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: D Scott Phillips <scott@os.amperecomputing.com>
Cc: Hardevsinh Palaniya <hardevsinh.palaniya@siliconsignals.io>
Cc: James Morse <james.morse@arm.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Pankaj Gupta <pankaj.gupta@amd.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <yang@os.amperecomputing.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 31d8edb5

mm/kasan/kasan_test_c.c

+136 −69
Original line number Diff line number Diff line
@@ -94,11 +94,14 @@ static void kasan_test_exit(struct kunit *test) 
}



/**

 * KUNIT_EXPECT_KASAN_FAIL - check that the executed expression produces a

 * KASAN report; causes a KUnit test failure otherwise.

 * KUNIT_EXPECT_KASAN_RESULT - checks whether the executed expression

 * produces a KASAN report; causes a KUnit test failure when the result

 * is different from @fail.

 *

 * @test: Currently executing KUnit test.

 * @expression: Expression that must produce a KASAN report.

 * @expr: Expression to be tested.

 * @expr_str: Expression to be tested encoded as a string.

 * @fail: Whether expression should produce a KASAN report.

 *

 * For hardware tag-based KASAN, when a synchronous tag fault happens, tag

 * checking is auto-disabled. When this happens, this test handler reenables
@@ -110,25 +113,29 @@ static void kasan_test_exit(struct kunit *test) 
 * Use READ/WRITE_ONCE() for the accesses and compiler barriers around the

 * expression to prevent that.

 *

 * In between KUNIT_EXPECT_KASAN_FAIL checks, test_status.report_found is kept

 * In between KUNIT_EXPECT_KASAN_RESULT checks, test_status.report_found is kept

 * as false. This allows detecting KASAN reports that happen outside of the

 * checks by asserting !test_status.report_found at the start of

 * KUNIT_EXPECT_KASAN_FAIL and in kasan_test_exit.

 * KUNIT_EXPECT_KASAN_RESULT and in kasan_test_exit.

 */

#define KUNIT_EXPECT_KASAN_FAIL(test, expression) do {			\

#define KUNIT_EXPECT_KASAN_RESULT(test, expr, expr_str, fail)		\

do {									\

	if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) &&				\

	    kasan_sync_fault_possible())				\

		migrate_disable();					\

	KUNIT_EXPECT_FALSE(test, READ_ONCE(test_status.report_found));	\

	barrier();							\

	expression;							\

	expr;								\

	barrier();							\

	if (kasan_async_fault_possible())				\

		kasan_force_async_fault();				\

	if (!READ_ONCE(test_status.report_found)) {			\

	if (READ_ONCE(test_status.report_found) != fail) {		\

		KUNIT_FAIL(test, KUNIT_SUBTEST_INDENT "KASAN failure"	\

				"expected in \"" #expression		\

				 "\", but none occurred");		\

				"%sexpected in \"" expr_str		\

				 "\", but %soccurred",			\

				(fail ? " " : " not "),		\

				(test_status.report_found ?		\

				 "" : "none "));			\

	}								\

	if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) &&				\

	    kasan_sync_fault_possible()) {				\
@@ -141,6 +148,34 @@ static void kasan_test_exit(struct kunit *test) 
	WRITE_ONCE(test_status.async_fault, false);			\

} while (0)



/*

 * KUNIT_EXPECT_KASAN_FAIL - check that the executed expression produces a

 * KASAN report; causes a KUnit test failure otherwise.

 *

 * @test: Currently executing KUnit test.

 * @expr: Expression that must produce a KASAN report.

 */

#define KUNIT_EXPECT_KASAN_FAIL(test, expr)			\

	KUNIT_EXPECT_KASAN_RESULT(test, expr, #expr, true)



/*

 * KUNIT_EXPECT_KASAN_FAIL_READ - check that the executed expression

 * produces a KASAN report when the write-only mode is not enabled;

 * causes a KUnit test failure otherwise.

 *

 * Note: At the moment, this macro does not check whether the produced

 * KASAN report is a report about a bad read access. It is only intended

 * for checking the write-only KASAN mode functionality without failing

 * KASAN tests.

 *

 * @test: Currently executing KUnit test.

 * @expr: Expression that must only produce a KASAN report

 *        when the write-only mode is not enabled.

 */

#define KUNIT_EXPECT_KASAN_FAIL_READ(test, expr)			\

	KUNIT_EXPECT_KASAN_RESULT(test, expr, #expr,			\

			!kasan_write_only_enabled())			\



#define KASAN_TEST_NEEDS_CONFIG_ON(test, config) do {			\

	if (!IS_ENABLED(config))					\

		kunit_skip((test), "Test requires " #config "=y");	\
@@ -183,7 +218,7 @@ static void kmalloc_oob_right(struct kunit *test) 
	KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + 5] = 'y');



	/* Out-of-bounds access past the aligned kmalloc object. */

	KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] =

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ptr[0] =

			ptr[size + KASAN_GRANULE_SIZE + 5]);



	kfree(ptr);
@@ -198,7 +233,7 @@ static void kmalloc_oob_left(struct kunit *test) 
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);



	OPTIMIZER_HIDE_VAR(ptr);

	KUNIT_EXPECT_KASAN_FAIL(test, *ptr = *(ptr - 1));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, *ptr = *(ptr - 1));

	kfree(ptr);

}
@@ -211,7 +246,7 @@ static void kmalloc_node_oob_right(struct kunit *test) 
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);



	OPTIMIZER_HIDE_VAR(ptr);

	KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = ptr[size]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ptr[0] = ptr[size]);

	kfree(ptr);

}
@@ -291,7 +326,7 @@ static void kmalloc_large_uaf(struct kunit *test) 
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);

	kfree(ptr);



	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr)[0]);

}



static void kmalloc_large_invalid_free(struct kunit *test)
@@ -323,7 +358,7 @@ static void page_alloc_oob_right(struct kunit *test) 
	ptr = page_address(pages);

	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);



	KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = ptr[size]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ptr[0] = ptr[size]);

	free_pages((unsigned long)ptr, order);

}
@@ -338,7 +373,7 @@ static void page_alloc_uaf(struct kunit *test) 
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);

	free_pages((unsigned long)ptr, order);



	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr)[0]);

}



static void krealloc_more_oob_helper(struct kunit *test,
@@ -458,7 +493,7 @@ static void krealloc_uaf(struct kunit *test) 


	KUNIT_EXPECT_KASAN_FAIL(test, ptr2 = krealloc(ptr1, size2, GFP_KERNEL));

	KUNIT_ASSERT_NULL(test, ptr2);

	KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)ptr1);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, *(volatile char *)ptr1);

}



static void kmalloc_oob_16(struct kunit *test)
@@ -501,7 +536,7 @@ static void kmalloc_uaf_16(struct kunit *test) 
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2);

	kfree(ptr2);



	KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 = *ptr2);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, *ptr1 = *ptr2);

	kfree(ptr1);

}
@@ -640,7 +675,7 @@ static void kmalloc_memmove_invalid_size(struct kunit *test) 
	memset((char *)ptr, 0, 64);

	OPTIMIZER_HIDE_VAR(ptr);

	OPTIMIZER_HIDE_VAR(invalid_size);

	KUNIT_EXPECT_KASAN_FAIL(test,

	KUNIT_EXPECT_KASAN_FAIL_READ(test,

			memmove((char *)ptr, (char *)ptr + 4, invalid_size));

	kfree(ptr);

}
@@ -654,7 +689,7 @@ static void kmalloc_uaf(struct kunit *test) 
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);



	kfree(ptr);

	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[8]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr)[8]);

}



static void kmalloc_uaf_memset(struct kunit *test)
@@ -701,7 +736,7 @@ static void kmalloc_uaf2(struct kunit *test) 
		goto again;

	}



	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr1)[40]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr1)[40]);

	KUNIT_EXPECT_PTR_NE(test, ptr1, ptr2);



	kfree(ptr2);
@@ -727,19 +762,19 @@ static void kmalloc_uaf3(struct kunit *test) 
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2);

	kfree(ptr2);



	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr1)[8]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr1)[8]);

}



static void kasan_atomics_helper(struct kunit *test, void *unsafe, void *safe)

{

	int *i_unsafe = unsafe;



	KUNIT_EXPECT_KASAN_FAIL(test, READ_ONCE(*i_unsafe));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, READ_ONCE(*i_unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, WRITE_ONCE(*i_unsafe, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, smp_load_acquire(i_unsafe));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, smp_load_acquire(i_unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, smp_store_release(i_unsafe, 42));



	KUNIT_EXPECT_KASAN_FAIL(test, atomic_read(unsafe));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, atomic_read(unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_set(unsafe, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_add(42, unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_sub(42, unsafe));
@@ -752,18 +787,31 @@ static void kasan_atomics_helper(struct kunit *test, void *unsafe, void *safe) 
	KUNIT_EXPECT_KASAN_FAIL(test, atomic_xchg(unsafe, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_cmpxchg(unsafe, 21, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_try_cmpxchg(unsafe, safe, 42));

	/*

	 * The result of the test below may vary due to garbage values of

	 * unsafe in write-only mode.

	 * Therefore, skip this test when KASAN is configured in write-only mode.

	 */

	if (!kasan_write_only_enabled())

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_try_cmpxchg(safe, unsafe, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_sub_and_test(42, unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_dec_and_test(unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_inc_and_test(unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_add_negative(42, unsafe));

	/*

	 * The result of the test below may vary due to garbage values of

	 * unsafe in write-only mode.

	 * Therefore, skip this test when KASAN is configured in write-only mode.

	 */

	if (!kasan_write_only_enabled()) {

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_add_unless(unsafe, 21, 42));

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_inc_not_zero(unsafe));

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_inc_unless_negative(unsafe));

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_dec_unless_positive(unsafe));

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_dec_if_positive(unsafe));

	}



	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_read(unsafe));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, atomic_long_read(unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_set(unsafe, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_add(42, unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_sub(42, unsafe));
@@ -776,17 +824,30 @@ static void kasan_atomics_helper(struct kunit *test, void *unsafe, void *safe) 
	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_xchg(unsafe, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_cmpxchg(unsafe, 21, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_try_cmpxchg(unsafe, safe, 42));

	/*

	 * The result of the test below may vary due to garbage values of

	 * unsafe in write-only mode.

	 * Therefore, skip this test when KASAN is configured in write-only mode.

	 */

	if (!kasan_write_only_enabled())

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_try_cmpxchg(safe, unsafe, 42));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_sub_and_test(42, unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_and_test(unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc_and_test(unsafe));

	KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_add_negative(42, unsafe));

	/*

	 * The result of the test below may vary due to garbage values of

	 * unsafe in write-only mode.

	 * Therefore, skip this test when KASAN is configured in write-only mode.

	 */

	if (!kasan_write_only_enabled()) {

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_add_unless(unsafe, 21, 42));

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc_not_zero(unsafe));

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc_unless_negative(unsafe));

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_unless_positive(unsafe));

		KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_if_positive(unsafe));

	}

}



static void kasan_atomics(struct kunit *test)

{
@@ -842,8 +903,8 @@ static void ksize_unpoisons_memory(struct kunit *test) 
	/* These must trigger a KASAN report. */

	if (IS_ENABLED(CONFIG_KASAN_GENERIC))

		KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size]);

	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size + 5]);

	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[real_size - 1]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr)[size + 5]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr)[real_size - 1]);



	kfree(ptr);

}
@@ -863,8 +924,8 @@ static void ksize_uaf(struct kunit *test) 


	OPTIMIZER_HIDE_VAR(ptr);

	KUNIT_EXPECT_KASAN_FAIL(test, ksize(ptr));

	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]);

	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr)[0]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr)[size]);

}



/*
@@ -899,7 +960,7 @@ static void rcu_uaf(struct kunit *test) 
	global_rcu_ptr = rcu_dereference_protected(

				(struct kasan_rcu_info __rcu *)ptr, NULL);



	KUNIT_EXPECT_KASAN_FAIL(test,

	KUNIT_EXPECT_KASAN_FAIL_READ(test,

			call_rcu(&global_rcu_ptr->rcu, rcu_uaf_reclaim);

			rcu_barrier());

}
@@ -924,7 +985,7 @@ static void workqueue_uaf(struct kunit *test) 
	queue_work(workqueue, work);

	destroy_workqueue(workqueue);



	KUNIT_EXPECT_KASAN_FAIL(test,

	KUNIT_EXPECT_KASAN_FAIL_READ(test,

			((volatile struct work_struct *)work)->data);

}
@@ -972,7 +1033,7 @@ static void kmem_cache_oob(struct kunit *test) 
		return;

	}



	KUNIT_EXPECT_KASAN_FAIL(test, *p = p[size + OOB_TAG_OFF]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, *p = p[size + OOB_TAG_OFF]);



	kmem_cache_free(cache, p);

	kmem_cache_destroy(cache);
@@ -1068,7 +1129,7 @@ static void kmem_cache_rcu_uaf(struct kunit *test) 
	 */

	rcu_barrier();



	KUNIT_EXPECT_KASAN_FAIL(test, READ_ONCE(*p));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, READ_ONCE(*p));



	kmem_cache_destroy(cache);

}
@@ -1246,7 +1307,7 @@ static void mempool_oob_right_helper(struct kunit *test, mempool_t *pool, size_t 
		KUNIT_EXPECT_KASAN_FAIL(test,

			((volatile char *)&elem[size])[0]);

	else

		KUNIT_EXPECT_KASAN_FAIL(test,

		KUNIT_EXPECT_KASAN_FAIL_READ(test,

			((volatile char *)&elem[round_up(size, KASAN_GRANULE_SIZE)])[0]);



	mempool_free(elem, pool);
@@ -1312,7 +1373,7 @@ static void mempool_uaf_helper(struct kunit *test, mempool_t *pool, bool page) 
	mempool_free(elem, pool);



	ptr = page ? page_address((struct page *)elem) : elem;

	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)ptr)[0]);

}



static void mempool_kmalloc_uaf(struct kunit *test)
@@ -1571,7 +1632,7 @@ static void kasan_memchr(struct kunit *test) 


	OPTIMIZER_HIDE_VAR(ptr);

	OPTIMIZER_HIDE_VAR(size);

	KUNIT_EXPECT_KASAN_FAIL(test,

	KUNIT_EXPECT_KASAN_FAIL_READ(test,

		kasan_ptr_result = memchr(ptr, '1', size + 1));



	kfree(ptr);
@@ -1598,7 +1659,7 @@ static void kasan_memcmp(struct kunit *test) 


	OPTIMIZER_HIDE_VAR(ptr);

	OPTIMIZER_HIDE_VAR(size);

	KUNIT_EXPECT_KASAN_FAIL(test,

	KUNIT_EXPECT_KASAN_FAIL_READ(test,

		kasan_int_result = memcmp(ptr, arr, size+1));

	kfree(ptr);

}
@@ -1635,7 +1696,7 @@ static void kasan_strings(struct kunit *test) 
			strscpy(ptr, src + 1, KASAN_GRANULE_SIZE));



	/* strscpy should fail if the first byte is unreadable. */

	KUNIT_EXPECT_KASAN_FAIL(test, strscpy(ptr, src + KASAN_GRANULE_SIZE,

	KUNIT_EXPECT_KASAN_FAIL_READ(test, strscpy(ptr, src + KASAN_GRANULE_SIZE,

					      KASAN_GRANULE_SIZE));



	kfree(src);
@@ -1648,17 +1709,17 @@ static void kasan_strings(struct kunit *test) 
	 * will likely point to zeroed byte.

	 */

	ptr += 16;

	KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result = strchr(ptr, '1'));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_ptr_result = strchr(ptr, '1'));



	KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result = strrchr(ptr, '1'));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_ptr_result = strrchr(ptr, '1'));



	KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strcmp(ptr, "2"));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result = strcmp(ptr, "2"));



	KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strncmp(ptr, "2", 1));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result = strncmp(ptr, "2", 1));



	KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strlen(ptr));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result = strlen(ptr));



	KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strnlen(ptr, 1));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result = strnlen(ptr, 1));

}



static void kasan_bitops_modify(struct kunit *test, int nr, void *addr)
@@ -1677,12 +1738,18 @@ static void kasan_bitops_test_and_modify(struct kunit *test, int nr, void *addr) 
{

	KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit(nr, addr));

	KUNIT_EXPECT_KASAN_FAIL(test, __test_and_set_bit(nr, addr));

	/*

	 * When KASAN is running in write-only mode,

	 * a fault won't occur when the bit is set.

	 * Therefore, skip the test_and_set_bit_lock test in write-only mode.

	 */

	if (!kasan_write_only_enabled())

		KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit_lock(nr, addr));

	KUNIT_EXPECT_KASAN_FAIL(test, test_and_clear_bit(nr, addr));

	KUNIT_EXPECT_KASAN_FAIL(test, __test_and_clear_bit(nr, addr));

	KUNIT_EXPECT_KASAN_FAIL(test, test_and_change_bit(nr, addr));

	KUNIT_EXPECT_KASAN_FAIL(test, __test_and_change_bit(nr, addr));

	KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = test_bit(nr, addr));

	KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result = test_bit(nr, addr));

	if (nr < 7)

		KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result =

				xor_unlock_is_negative_byte(1 << nr, addr));
@@ -1806,7 +1873,7 @@ static void vmalloc_oob(struct kunit *test) 
		KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[size]);



	/* An aligned access into the first out-of-bounds granule. */

	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[size + 5]);

	KUNIT_EXPECT_KASAN_FAIL_READ(test, ((volatile char *)v_ptr)[size + 5]);



	/* Check that in-bounds accesses to the physical page are valid. */

	page = vmalloc_to_page(v_ptr);
@@ -2083,15 +2150,15 @@ static void copy_user_test_oob(struct kunit *test) 


	KUNIT_EXPECT_KASAN_FAIL(test,

		unused = copy_from_user(kmem, usermem, size + 1));

	KUNIT_EXPECT_KASAN_FAIL(test,

	KUNIT_EXPECT_KASAN_FAIL_READ(test,

		unused = copy_to_user(usermem, kmem, size + 1));

	KUNIT_EXPECT_KASAN_FAIL(test,

		unused = __copy_from_user(kmem, usermem, size + 1));

	KUNIT_EXPECT_KASAN_FAIL(test,

	KUNIT_EXPECT_KASAN_FAIL_READ(test,

		unused = __copy_to_user(usermem, kmem, size + 1));

	KUNIT_EXPECT_KASAN_FAIL(test,

		unused = __copy_from_user_inatomic(kmem, usermem, size + 1));

	KUNIT_EXPECT_KASAN_FAIL(test,

	KUNIT_EXPECT_KASAN_FAIL_READ(test,

		unused = __copy_to_user_inatomic(usermem, kmem, size + 1));



	/*