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AJvYcCW9cbG8cpv30B0F4Fyyrt6zgCxFmWfGsEX+f+MyqAFm/zfwx0OsBP8IPkkIdaiZRA76Fcs/6tSHFUd1@vger.kernel.org, AJvYcCW9o2sS/s/LYNUIGd+g3CnJOahKHZ5WUu1H5W5rh9ifucpYqmNLjlwHzFsoOYgSfCtpHwf/RwOfzYY=@vger.kernel.org, AJvYcCXCKcKIB86yujMWFW8V7pq6eSq95oo3kEIWd0nS6fIBAHcn/ctxNDUZ0ECGfwUODejx7R8eNAmz9pwl5SuW@vger.kernel.org X-Gm-Message-State: AOJu0YxH77OTNoihH6hcGr1U/QjAs8SmWcB9rktHkEwKGMhoCexTar34 BIJTRwko+icS4Lkw1gTOoF2BXzo2y3H39H1ffPACGmjLRzgFBjBB1q9m0eDx7ExUaPiRJe4djPU 0zDCnwpEGOyLmf1MgcJj4g1ostpK5ZiA= X-Gm-Gg: ASbGncsV7p+V+f5/80o0LTvsmfgLRZF7fIy/e2lCwJH9KYb7CBHpAjrU6QjUkic0zDQ Jh9qUktl+pDYR+YVRtpo/8RiDnB2URxEcqvha+oEsGrkdltw5xHV8sZp0GAApkBBpvSmHoAwG6b NYi1EZ1AkAKysWfn1OtudnZtdwK9ojeul+lBC9JXmS1KIskDZVHzCE/i9hOP5qQ5D2yAVSAi6hJ w5iwm7o X-Google-Smtp-Source: AGHT+IG4+8guXK6dPRv/VXyLxQ/FpO33e3SLX5O7uf6Y+CRIlj9YZLYgvT0PmeUaSWp86M24p22so0J1gqtN5Ff9B7s= X-Received: by 2002:a05:6000:2890:b0:3de:c5b3:dda2 with SMTP id ffacd0b85a97d-3dec5b3e033mr1667450f8f.34.1756903786262; Wed, 03 Sep 2025 05:49:46 -0700 (PDT) Precedence: bulk X-Mailing-List: workflows@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20250901104623.402172-1-yeoreum.yun@arm.com> <20250901104623.402172-3-yeoreum.yun@arm.com> In-Reply-To: <20250901104623.402172-3-yeoreum.yun@arm.com> From: Andrey Konovalov Date: Wed, 3 Sep 2025 14:49:34 +0200 X-Gm-Features: Ac12FXyu_2MW1p9hqzVMXrUjzZRBuRkpC_vIzVYx2h5zKsSvlwoHHiBIosQjurc Message-ID: Subject: Re: [PATCH v6 2/2] kasan: apply write-only mode in kasan kunit testcases To: Yeoreum Yun Cc: ryabinin.a.a@gmail.com, glider@google.com, dvyukov@google.com, vincenzo.frascino@arm.com, corbet@lwn.net, catalin.marinas@arm.com, will@kernel.org, akpm@linux-foundation.org, scott@os.amperecomputing.com, jhubbard@nvidia.com, pankaj.gupta@amd.com, leitao@debian.org, kaleshsingh@google.com, maz@kernel.org, broonie@kernel.org, oliver.upton@linux.dev, james.morse@arm.com, ardb@kernel.org, hardevsinh.palaniya@siliconsignals.io, david@redhat.com, yang@os.amperecomputing.com, kasan-dev@googlegroups.com, workflows@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, Sep 1, 2025 at 12:46=E2=80=AFPM Yeoreum Yun w= rote: > > 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. > > Signed-off-by: Yeoreum Yun > --- > mm/kasan/kasan_test_c.c | 204 ++++++++++++++++++++++++++-------------- > 1 file changed, 135 insertions(+), 69 deletions(-) > > diff --git a/mm/kasan/kasan_test_c.c b/mm/kasan/kasan_test_c.c > index e0968acc03aa..8b3bb33603e1 100644 > --- a/mm/kasan/kasan_test_c.c > +++ b/mm/kasan/kasan_test_c.c > @@ -94,11 +94,13 @@ 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 - check that the executed expression > + * causes a KUnit test failure when the result is different from @fail. What I meant here was: 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, t= ag > * checking is auto-disabled. When this happens, this test handler reena= bles > @@ -110,25 +112,29 @@ static void kasan_test_exit(struct kunit *test) > * Use READ/WRITE_ONCE() for the accesses and compiler barriers around t= he > * expression to prevent that. > * > - * In between KUNIT_EXPECT_KASAN_FAIL checks, test_status.report_found i= s 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)) { \ > - KUNIT_FAIL(test, KUNIT_SUBTEST_INDENT "KASAN failure " \ > - "expected in \"" #expression \ > - "\", but none occurred"); \ > + if (READ_ONCE(test_status.report_found) !=3D fail) { = \ > + KUNIT_FAIL(test, KUNIT_SUBTEST_INDENT "KASAN failure" \ > + "%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 +147,34 @@ 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 "=3Dy"); = \ > @@ -183,8 +217,8 @@ static void kmalloc_oob_right(struct kunit *test) > KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + 5] =3D 'y'); > > /* Out-of-bounds access past the aligned kmalloc object. */ > - KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] =3D > - ptr[size + KASAN_GRANULE_SIZE + 5= ]); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, ptr[0] =3D > + ptr[size + KASAN_GRANULE_SIZE + 5]); > > kfree(ptr); > } > @@ -198,7 +232,7 @@ 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 =3D *(ptr - 1)); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, *ptr =3D *(ptr - 1)); > kfree(ptr); > } > > @@ -211,7 +245,7 @@ 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] =3D ptr[size]); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, ptr[0] =3D ptr[size]); > kfree(ptr); > } > > @@ -291,7 +325,7 @@ 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 +357,7 @@ static void page_alloc_oob_right(struct kunit *test) > ptr =3D page_address(pages); > KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); > > - KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] =3D ptr[size]); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, ptr[0] =3D ptr[size]); > free_pages((unsigned long)ptr, order); > } > > @@ -338,7 +372,7 @@ 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 +492,7 @@ static void krealloc_uaf(struct kunit *test) > > KUNIT_EXPECT_KASAN_FAIL(test, ptr2 =3D 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 +535,7 @@ static void kmalloc_uaf_16(struct kunit *test) > KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); > kfree(ptr2); > > - KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 =3D *ptr2); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, *ptr1 =3D *ptr2); > kfree(ptr1); > } > > @@ -640,8 +674,8 @@ 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, > - memmove((char *)ptr, (char *)ptr + 4, invalid_size)); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, > + memmove((char *)ptr, (char *)ptr + 4, invalid_siz= e)); > kfree(ptr); > } > > @@ -654,7 +688,7 @@ 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 +735,7 @@ 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 +761,19 @@ 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 =3D 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 +786,31 @@ 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= )); > - KUNIT_EXPECT_KASAN_FAIL(test, atomic_try_cmpxchg(safe, unsafe, 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-on= ly mode. > + */ > + if (!kasan_write_only_enabled()) > + KUNIT_EXPECT_KASAN_FAIL(test, atomic_try_cmpxchg(safe, un= safe, 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)); > - 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)); > + /* > + * 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-on= ly mode. > + */ > + if (!kasan_write_only_enabled()) { > + KUNIT_EXPECT_KASAN_FAIL(test, atomic_add_unless(unsafe, 2= 1, 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(unsa= fe)); > + } > > - 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)); > @@ -776,16 +823,29 @@ 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, saf= e, 42)); > - KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_try_cmpxchg(safe, unsaf= e, 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-on= ly mode. > + */ > + if (!kasan_write_only_enabled()) > + KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_try_cmpxchg(saf= e, 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= )); > - 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(uns= afe)); > - KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_unless_positive(uns= afe)); > - KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_if_positive(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-on= ly mode. > + */ > + if (!kasan_write_only_enabled()) { > + KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_add_unless(unsa= fe, 21, 42)); > + KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc_not_zero(un= safe)); > + KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_inc_unless_nega= tive(unsafe)); > + KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_unless_posi= tive(unsafe)); > + KUNIT_EXPECT_KASAN_FAIL(test, atomic_long_dec_if_positive= (unsafe)); > + } > } > > static void kasan_atomics(struct kunit *test) > @@ -842,8 +902,8 @@ 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_si= ze - 1]); > > kfree(ptr); > } > @@ -863,8 +923,8 @@ 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]); > } > > /* > @@ -899,9 +959,9 @@ static void rcu_uaf(struct kunit *test) > global_rcu_ptr =3D rcu_dereference_protected( > (struct kasan_rcu_info __rcu *)ptr, NULL)= ; > > - KUNIT_EXPECT_KASAN_FAIL(test, > - call_rcu(&global_rcu_ptr->rcu, rcu_uaf_reclaim); > - rcu_barrier()); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, > + call_rcu(&global_rcu_ptr->rcu, rcu_uaf_reclaim); > + rcu_barrier()); > } > > static void workqueue_uaf_work(struct work_struct *work) > @@ -924,8 +984,8 @@ static void workqueue_uaf(struct kunit *test) > queue_work(workqueue, work); > destroy_workqueue(workqueue); > > - KUNIT_EXPECT_KASAN_FAIL(test, > - ((volatile struct work_struct *)work)->data); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, > + ((volatile struct work_struct *)work)->data); > } > > static void kfree_via_page(struct kunit *test) > @@ -972,7 +1032,7 @@ static void kmem_cache_oob(struct kunit *test) > return; > } > > - KUNIT_EXPECT_KASAN_FAIL(test, *p =3D p[size + OOB_TAG_OFF]); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, *p =3D p[size + OOB_TAG_OFF]); > > kmem_cache_free(cache, p); > kmem_cache_destroy(cache); > @@ -1068,7 +1128,7 @@ 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); > } > @@ -1207,7 +1267,7 @@ 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_GRAN= ULE_SIZE)])[0]); > > mempool_free(elem, pool); > @@ -1273,7 +1333,7 @@ static void mempool_uaf_helper(struct kunit *test, = mempool_t *pool, bool page) > mempool_free(elem, pool); > > ptr =3D 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) > @@ -1532,7 +1592,7 @@ 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 =3D memchr(ptr, '1', size + 1)); > > kfree(ptr); > @@ -1559,7 +1619,7 @@ 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 =3D memcmp(ptr, arr, size+1)); > kfree(ptr); > } > @@ -1594,7 +1654,7 @@ 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_SI= ZE, > + KUNIT_EXPECT_KASAN_FAIL_READ(test, strscpy(ptr, src + KASAN_GRANU= LE_SIZE, > KASAN_GRANULE_SIZE)); > > kfree(src); > @@ -1607,17 +1667,17 @@ static void kasan_strings(struct kunit *test) > * will likely point to zeroed byte. > */ > ptr +=3D 16; > - KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result =3D strchr(ptr, '1= ')); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_ptr_result =3D strchr(pt= r, '1')); > > - KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result =3D strrchr(ptr, '= 1')); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_ptr_result =3D strrchr(p= tr, '1')); > > - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result =3D strcmp(ptr, "2= ")); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result =3D strcmp(pt= r, "2")); > > - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result =3D strncmp(ptr, "= 2", 1)); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result =3D strncmp(p= tr, "2", 1)); > > - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result =3D strlen(ptr)); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result =3D strlen(pt= r)); > > - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result =3D strnlen(ptr, 1= )); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result =3D strnlen(p= tr, 1)); > } > > static void kasan_bitops_modify(struct kunit *test, int nr, void *addr) > @@ -1636,12 +1696,18 @@ static void kasan_bitops_test_and_modify(struct k= unit *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)); > - KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit_lock(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 m= ode. > + */ > + if (!kasan_write_only_enabled()) > + KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit_lock(nr, a= ddr)); > 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 =3D test_bit(nr, a= ddr)); > + KUNIT_EXPECT_KASAN_FAIL_READ(test, kasan_int_result =3D test_bit(= nr, addr)); > if (nr < 7) > KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result =3D > xor_unlock_is_negative_byte(1 << nr, addr= )); > @@ -1765,7 +1831,7 @@ static void vmalloc_oob(struct kunit *test) > KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[si= ze]); > > /* 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 =3D vmalloc_to_page(v_ptr); > @@ -2042,15 +2108,15 @@ static void copy_user_test_oob(struct kunit *test= ) > > KUNIT_EXPECT_KASAN_FAIL(test, > unused =3D copy_from_user(kmem, usermem, size + 1)); > - KUNIT_EXPECT_KASAN_FAIL(test, > + KUNIT_EXPECT_KASAN_FAIL_READ(test, > unused =3D copy_to_user(usermem, kmem, size + 1)); > KUNIT_EXPECT_KASAN_FAIL(test, > unused =3D __copy_from_user(kmem, usermem, size + 1)); > - KUNIT_EXPECT_KASAN_FAIL(test, > + KUNIT_EXPECT_KASAN_FAIL_READ(test, > unused =3D __copy_to_user(usermem, kmem, size + 1)); > KUNIT_EXPECT_KASAN_FAIL(test, > unused =3D __copy_from_user_inatomic(kmem, usermem, size = + 1)); > - KUNIT_EXPECT_KASAN_FAIL(test, > + KUNIT_EXPECT_KASAN_FAIL_READ(test, > unused =3D __copy_to_user_inatomic(usermem, kmem, size + = 1)); > > /* > -- > LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7} > Reviewed-by: Andrey Konovalov