1 // SPDX-License-Identifier: GPL-2.0-only
4 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
5 * Author: Andrey Ryabinin <a.ryabinin@samsung.com>
8 #include <linux/bitops.h>
9 #include <linux/delay.h>
10 #include <linux/kasan.h>
11 #include <linux/kernel.h>
13 #include <linux/mman.h>
14 #include <linux/module.h>
15 #include <linux/printk.h>
16 #include <linux/random.h>
17 #include <linux/slab.h>
18 #include <linux/string.h>
19 #include <linux/uaccess.h>
21 #include <linux/vmalloc.h>
25 #include <kunit/test.h>
27 #include "../mm/kasan/kasan.h"
29 #define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_GRANULE_SIZE)
32 * Some tests use these global variables to store return values from function
33 * calls that could otherwise be eliminated by the compiler as dead code.
35 void *kasan_ptr_result
;
38 static struct kunit_resource resource
;
39 static struct kunit_kasan_expectation fail_data
;
40 static bool multishot
;
43 * Temporarily enable multi-shot mode. Otherwise, KASAN would only report the
44 * first detected bug and panic the kernel if panic_on_warn is enabled. For
45 * hardware tag-based KASAN also allow tag checking to be reenabled for each
46 * test, see the comment for KUNIT_EXPECT_KASAN_FAIL().
48 static int kasan_test_init(struct kunit
*test
)
50 if (!kasan_enabled()) {
51 kunit_err(test
, "can't run KASAN tests with KASAN disabled");
55 multishot
= kasan_save_enable_multi_shot();
56 fail_data
.report_found
= false;
57 kunit_add_named_resource(test
, NULL
, NULL
, &resource
,
58 "kasan_data", &fail_data
);
62 static void kasan_test_exit(struct kunit
*test
)
64 kasan_restore_multi_shot(multishot
);
65 KUNIT_EXPECT_FALSE(test
, fail_data
.report_found
);
69 * KUNIT_EXPECT_KASAN_FAIL() - check that the executed expression produces a
70 * KASAN report; causes a test failure otherwise. This relies on a KUnit
71 * resource named "kasan_data". Do not use this name for KUnit resources
72 * outside of KASAN tests.
74 * For hardware tag-based KASAN in sync mode, when a tag fault happens, tag
75 * checking is auto-disabled. When this happens, this test handler reenables
76 * tag checking. As tag checking can be only disabled or enabled per CPU,
77 * this handler disables migration (preemption).
79 * Since the compiler doesn't see that the expression can change the fail_data
80 * fields, it can reorder or optimize away the accesses to those fields.
81 * Use READ/WRITE_ONCE() for the accesses and compiler barriers around the
82 * expression to prevent that.
84 * In between KUNIT_EXPECT_KASAN_FAIL checks, fail_data.report_found is kept as
85 * false. This allows detecting KASAN reports that happen outside of the checks
86 * by asserting !fail_data.report_found at the start of KUNIT_EXPECT_KASAN_FAIL
87 * and in kasan_test_exit.
89 #define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \
90 if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \
91 !kasan_async_mode_enabled()) \
93 KUNIT_EXPECT_FALSE(test, READ_ONCE(fail_data.report_found)); \
97 if (!READ_ONCE(fail_data.report_found)) { \
98 KUNIT_FAIL(test, KUNIT_SUBTEST_INDENT "KASAN failure " \
99 "expected in \"" #expression \
100 "\", but none occurred"); \
102 if (IS_ENABLED(CONFIG_KASAN_HW_TAGS)) { \
103 if (READ_ONCE(fail_data.report_found)) \
104 kasan_enable_tagging_sync(); \
107 WRITE_ONCE(fail_data.report_found, false); \
110 #define KASAN_TEST_NEEDS_CONFIG_ON(test, config) do { \
111 if (!IS_ENABLED(config)) \
112 kunit_skip((test), "Test requires " #config "=y"); \
115 #define KASAN_TEST_NEEDS_CONFIG_OFF(test, config) do { \
116 if (IS_ENABLED(config)) \
117 kunit_skip((test), "Test requires " #config "=n"); \
120 static void kmalloc_oob_right(struct kunit
*test
)
123 size_t size
= 128 - KASAN_GRANULE_SIZE
- 5;
125 ptr
= kmalloc(size
, GFP_KERNEL
);
126 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
129 * An unaligned access past the requested kmalloc size.
130 * Only generic KASAN can precisely detect these.
132 if (IS_ENABLED(CONFIG_KASAN_GENERIC
))
133 KUNIT_EXPECT_KASAN_FAIL(test
, ptr
[size
] = 'x');
136 * An aligned access into the first out-of-bounds granule that falls
137 * within the aligned kmalloc object.
139 KUNIT_EXPECT_KASAN_FAIL(test
, ptr
[size
+ 5] = 'y');
141 /* Out-of-bounds access past the aligned kmalloc object. */
142 KUNIT_EXPECT_KASAN_FAIL(test
, ptr
[0] =
143 ptr
[size
+ KASAN_GRANULE_SIZE
+ 5]);
148 static void kmalloc_oob_left(struct kunit
*test
)
153 ptr
= kmalloc(size
, GFP_KERNEL
);
154 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
156 KUNIT_EXPECT_KASAN_FAIL(test
, *ptr
= *(ptr
- 1));
160 static void kmalloc_node_oob_right(struct kunit
*test
)
165 ptr
= kmalloc_node(size
, GFP_KERNEL
, 0);
166 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
168 KUNIT_EXPECT_KASAN_FAIL(test
, ptr
[0] = ptr
[size
]);
173 * These kmalloc_pagealloc_* tests try allocating a memory chunk that doesn't
174 * fit into a slab cache and therefore is allocated via the page allocator
175 * fallback. Since this kind of fallback is only implemented for SLUB, these
176 * tests are limited to that allocator.
178 static void kmalloc_pagealloc_oob_right(struct kunit
*test
)
181 size_t size
= KMALLOC_MAX_CACHE_SIZE
+ 10;
183 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_SLUB
);
185 ptr
= kmalloc(size
, GFP_KERNEL
);
186 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
188 KUNIT_EXPECT_KASAN_FAIL(test
, ptr
[size
+ OOB_TAG_OFF
] = 0);
193 static void kmalloc_pagealloc_uaf(struct kunit
*test
)
196 size_t size
= KMALLOC_MAX_CACHE_SIZE
+ 10;
198 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_SLUB
);
200 ptr
= kmalloc(size
, GFP_KERNEL
);
201 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
204 KUNIT_EXPECT_KASAN_FAIL(test
, ((volatile char *)ptr
)[0]);
207 static void kmalloc_pagealloc_invalid_free(struct kunit
*test
)
210 size_t size
= KMALLOC_MAX_CACHE_SIZE
+ 10;
212 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_SLUB
);
214 ptr
= kmalloc(size
, GFP_KERNEL
);
215 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
217 KUNIT_EXPECT_KASAN_FAIL(test
, kfree(ptr
+ 1));
220 static void pagealloc_oob_right(struct kunit
*test
)
225 size_t size
= (1UL << (PAGE_SHIFT
+ order
));
228 * With generic KASAN page allocations have no redzones, thus
229 * out-of-bounds detection is not guaranteed.
230 * See https://bugzilla.kernel.org/show_bug.cgi?id=210503.
232 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_KASAN_GENERIC
);
234 pages
= alloc_pages(GFP_KERNEL
, order
);
235 ptr
= page_address(pages
);
236 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
238 KUNIT_EXPECT_KASAN_FAIL(test
, ptr
[0] = ptr
[size
]);
239 free_pages((unsigned long)ptr
, order
);
242 static void pagealloc_uaf(struct kunit
*test
)
248 pages
= alloc_pages(GFP_KERNEL
, order
);
249 ptr
= page_address(pages
);
250 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
251 free_pages((unsigned long)ptr
, order
);
253 KUNIT_EXPECT_KASAN_FAIL(test
, ((volatile char *)ptr
)[0]);
256 static void kmalloc_large_oob_right(struct kunit
*test
)
259 size_t size
= KMALLOC_MAX_CACHE_SIZE
- 256;
262 * Allocate a chunk that is large enough, but still fits into a slab
263 * and does not trigger the page allocator fallback in SLUB.
265 ptr
= kmalloc(size
, GFP_KERNEL
);
266 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
268 KUNIT_EXPECT_KASAN_FAIL(test
, ptr
[size
] = 0);
272 static void krealloc_more_oob_helper(struct kunit
*test
,
273 size_t size1
, size_t size2
)
278 KUNIT_ASSERT_LT(test
, size1
, size2
);
279 middle
= size1
+ (size2
- size1
) / 2;
281 ptr1
= kmalloc(size1
, GFP_KERNEL
);
282 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr1
);
284 ptr2
= krealloc(ptr1
, size2
, GFP_KERNEL
);
285 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr2
);
287 /* All offsets up to size2 must be accessible. */
288 ptr2
[size1
- 1] = 'x';
291 ptr2
[size2
- 1] = 'x';
293 /* Generic mode is precise, so unaligned size2 must be inaccessible. */
294 if (IS_ENABLED(CONFIG_KASAN_GENERIC
))
295 KUNIT_EXPECT_KASAN_FAIL(test
, ptr2
[size2
] = 'x');
297 /* For all modes first aligned offset after size2 must be inaccessible. */
298 KUNIT_EXPECT_KASAN_FAIL(test
,
299 ptr2
[round_up(size2
, KASAN_GRANULE_SIZE
)] = 'x');
304 static void krealloc_less_oob_helper(struct kunit
*test
,
305 size_t size1
, size_t size2
)
310 KUNIT_ASSERT_LT(test
, size2
, size1
);
311 middle
= size2
+ (size1
- size2
) / 2;
313 ptr1
= kmalloc(size1
, GFP_KERNEL
);
314 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr1
);
316 ptr2
= krealloc(ptr1
, size2
, GFP_KERNEL
);
317 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr2
);
319 /* Must be accessible for all modes. */
320 ptr2
[size2
- 1] = 'x';
322 /* Generic mode is precise, so unaligned size2 must be inaccessible. */
323 if (IS_ENABLED(CONFIG_KASAN_GENERIC
))
324 KUNIT_EXPECT_KASAN_FAIL(test
, ptr2
[size2
] = 'x');
326 /* For all modes first aligned offset after size2 must be inaccessible. */
327 KUNIT_EXPECT_KASAN_FAIL(test
,
328 ptr2
[round_up(size2
, KASAN_GRANULE_SIZE
)] = 'x');
331 * For all modes all size2, middle, and size1 should land in separate
332 * granules and thus the latter two offsets should be inaccessible.
334 KUNIT_EXPECT_LE(test
, round_up(size2
, KASAN_GRANULE_SIZE
),
335 round_down(middle
, KASAN_GRANULE_SIZE
));
336 KUNIT_EXPECT_LE(test
, round_up(middle
, KASAN_GRANULE_SIZE
),
337 round_down(size1
, KASAN_GRANULE_SIZE
));
338 KUNIT_EXPECT_KASAN_FAIL(test
, ptr2
[middle
] = 'x');
339 KUNIT_EXPECT_KASAN_FAIL(test
, ptr2
[size1
- 1] = 'x');
340 KUNIT_EXPECT_KASAN_FAIL(test
, ptr2
[size1
] = 'x');
345 static void krealloc_more_oob(struct kunit
*test
)
347 krealloc_more_oob_helper(test
, 201, 235);
350 static void krealloc_less_oob(struct kunit
*test
)
352 krealloc_less_oob_helper(test
, 235, 201);
355 static void krealloc_pagealloc_more_oob(struct kunit
*test
)
357 /* page_alloc fallback in only implemented for SLUB. */
358 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_SLUB
);
360 krealloc_more_oob_helper(test
, KMALLOC_MAX_CACHE_SIZE
+ 201,
361 KMALLOC_MAX_CACHE_SIZE
+ 235);
364 static void krealloc_pagealloc_less_oob(struct kunit
*test
)
366 /* page_alloc fallback in only implemented for SLUB. */
367 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_SLUB
);
369 krealloc_less_oob_helper(test
, KMALLOC_MAX_CACHE_SIZE
+ 235,
370 KMALLOC_MAX_CACHE_SIZE
+ 201);
374 * Check that krealloc() detects a use-after-free, returns NULL,
375 * and doesn't unpoison the freed object.
377 static void krealloc_uaf(struct kunit
*test
)
383 ptr1
= kmalloc(size1
, GFP_KERNEL
);
384 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr1
);
387 KUNIT_EXPECT_KASAN_FAIL(test
, ptr2
= krealloc(ptr1
, size2
, GFP_KERNEL
));
388 KUNIT_ASSERT_PTR_EQ(test
, (void *)ptr2
, NULL
);
389 KUNIT_EXPECT_KASAN_FAIL(test
, *(volatile char *)ptr1
);
392 static void kmalloc_oob_16(struct kunit
*test
)
398 /* This test is specifically crafted for the generic mode. */
399 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_GENERIC
);
401 ptr1
= kmalloc(sizeof(*ptr1
) - 3, GFP_KERNEL
);
402 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr1
);
404 ptr2
= kmalloc(sizeof(*ptr2
), GFP_KERNEL
);
405 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr2
);
407 KUNIT_EXPECT_KASAN_FAIL(test
, *ptr1
= *ptr2
);
412 static void kmalloc_uaf_16(struct kunit
*test
)
418 ptr1
= kmalloc(sizeof(*ptr1
), GFP_KERNEL
);
419 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr1
);
421 ptr2
= kmalloc(sizeof(*ptr2
), GFP_KERNEL
);
422 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr2
);
425 KUNIT_EXPECT_KASAN_FAIL(test
, *ptr1
= *ptr2
);
430 * Note: in the memset tests below, the written range touches both valid and
431 * invalid memory. This makes sure that the instrumentation does not only check
432 * the starting address but the whole range.
435 static void kmalloc_oob_memset_2(struct kunit
*test
)
438 size_t size
= 128 - KASAN_GRANULE_SIZE
;
440 ptr
= kmalloc(size
, GFP_KERNEL
);
441 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
443 KUNIT_EXPECT_KASAN_FAIL(test
, memset(ptr
+ size
- 1, 0, 2));
447 static void kmalloc_oob_memset_4(struct kunit
*test
)
450 size_t size
= 128 - KASAN_GRANULE_SIZE
;
452 ptr
= kmalloc(size
, GFP_KERNEL
);
453 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
455 KUNIT_EXPECT_KASAN_FAIL(test
, memset(ptr
+ size
- 3, 0, 4));
459 static void kmalloc_oob_memset_8(struct kunit
*test
)
462 size_t size
= 128 - KASAN_GRANULE_SIZE
;
464 ptr
= kmalloc(size
, GFP_KERNEL
);
465 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
467 KUNIT_EXPECT_KASAN_FAIL(test
, memset(ptr
+ size
- 7, 0, 8));
471 static void kmalloc_oob_memset_16(struct kunit
*test
)
474 size_t size
= 128 - KASAN_GRANULE_SIZE
;
476 ptr
= kmalloc(size
, GFP_KERNEL
);
477 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
479 KUNIT_EXPECT_KASAN_FAIL(test
, memset(ptr
+ size
- 15, 0, 16));
483 static void kmalloc_oob_in_memset(struct kunit
*test
)
486 size_t size
= 128 - KASAN_GRANULE_SIZE
;
488 ptr
= kmalloc(size
, GFP_KERNEL
);
489 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
491 KUNIT_EXPECT_KASAN_FAIL(test
,
492 memset(ptr
, 0, size
+ KASAN_GRANULE_SIZE
));
496 static void kmalloc_memmove_invalid_size(struct kunit
*test
)
500 volatile size_t invalid_size
= -2;
503 * Hardware tag-based mode doesn't check memmove for negative size.
504 * As a result, this test introduces a side-effect memory corruption,
505 * which can result in a crash.
507 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_KASAN_HW_TAGS
);
509 ptr
= kmalloc(size
, GFP_KERNEL
);
510 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
512 memset((char *)ptr
, 0, 64);
513 KUNIT_EXPECT_KASAN_FAIL(test
,
514 memmove((char *)ptr
, (char *)ptr
+ 4, invalid_size
));
518 static void kmalloc_uaf(struct kunit
*test
)
523 ptr
= kmalloc(size
, GFP_KERNEL
);
524 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
527 KUNIT_EXPECT_KASAN_FAIL(test
, ((volatile char *)ptr
)[8]);
530 static void kmalloc_uaf_memset(struct kunit
*test
)
536 * Only generic KASAN uses quarantine, which is required to avoid a
537 * kernel memory corruption this test causes.
539 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_GENERIC
);
541 ptr
= kmalloc(size
, GFP_KERNEL
);
542 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
545 KUNIT_EXPECT_KASAN_FAIL(test
, memset(ptr
, 0, size
));
548 static void kmalloc_uaf2(struct kunit
*test
)
555 ptr1
= kmalloc(size
, GFP_KERNEL
);
556 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr1
);
560 ptr2
= kmalloc(size
, GFP_KERNEL
);
561 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr2
);
564 * For tag-based KASAN ptr1 and ptr2 tags might happen to be the same.
565 * Allow up to 16 attempts at generating different tags.
567 if (!IS_ENABLED(CONFIG_KASAN_GENERIC
) && ptr1
== ptr2
&& counter
++ < 16) {
572 KUNIT_EXPECT_KASAN_FAIL(test
, ((volatile char *)ptr1
)[40]);
573 KUNIT_EXPECT_PTR_NE(test
, ptr1
, ptr2
);
578 static void kfree_via_page(struct kunit
*test
)
583 unsigned long offset
;
585 ptr
= kmalloc(size
, GFP_KERNEL
);
586 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
588 page
= virt_to_page(ptr
);
589 offset
= offset_in_page(ptr
);
590 kfree(page_address(page
) + offset
);
593 static void kfree_via_phys(struct kunit
*test
)
599 ptr
= kmalloc(size
, GFP_KERNEL
);
600 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
602 phys
= virt_to_phys(ptr
);
603 kfree(phys_to_virt(phys
));
606 static void kmem_cache_oob(struct kunit
*test
)
610 struct kmem_cache
*cache
;
612 cache
= kmem_cache_create("test_cache", size
, 0, 0, NULL
);
613 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, cache
);
615 p
= kmem_cache_alloc(cache
, GFP_KERNEL
);
617 kunit_err(test
, "Allocation failed: %s\n", __func__
);
618 kmem_cache_destroy(cache
);
622 KUNIT_EXPECT_KASAN_FAIL(test
, *p
= p
[size
+ OOB_TAG_OFF
]);
624 kmem_cache_free(cache
, p
);
625 kmem_cache_destroy(cache
);
628 static void kmem_cache_accounted(struct kunit
*test
)
633 struct kmem_cache
*cache
;
635 cache
= kmem_cache_create("test_cache", size
, 0, SLAB_ACCOUNT
, NULL
);
636 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, cache
);
639 * Several allocations with a delay to allow for lazy per memcg kmem
642 for (i
= 0; i
< 5; i
++) {
643 p
= kmem_cache_alloc(cache
, GFP_KERNEL
);
647 kmem_cache_free(cache
, p
);
652 kmem_cache_destroy(cache
);
655 static void kmem_cache_bulk(struct kunit
*test
)
657 struct kmem_cache
*cache
;
663 cache
= kmem_cache_create("test_cache", size
, 0, 0, NULL
);
664 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, cache
);
666 ret
= kmem_cache_alloc_bulk(cache
, GFP_KERNEL
, ARRAY_SIZE(p
), (void **)&p
);
668 kunit_err(test
, "Allocation failed: %s\n", __func__
);
669 kmem_cache_destroy(cache
);
673 for (i
= 0; i
< ARRAY_SIZE(p
); i
++)
674 p
[i
][0] = p
[i
][size
- 1] = 42;
676 kmem_cache_free_bulk(cache
, ARRAY_SIZE(p
), (void **)&p
);
677 kmem_cache_destroy(cache
);
680 static char global_array
[10];
682 static void kasan_global_oob(struct kunit
*test
)
685 * Deliberate out-of-bounds access. To prevent CONFIG_UBSAN_LOCAL_BOUNDS
686 * from failing here and panicking the kernel, access the array via a
687 * volatile pointer, which will prevent the compiler from being able to
688 * determine the array bounds.
690 * This access uses a volatile pointer to char (char *volatile) rather
691 * than the more conventional pointer to volatile char (volatile char *)
692 * because we want to prevent the compiler from making inferences about
693 * the pointer itself (i.e. its array bounds), not the data that it
696 char *volatile array
= global_array
;
697 char *p
= &array
[ARRAY_SIZE(global_array
) + 3];
699 /* Only generic mode instruments globals. */
700 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_GENERIC
);
702 KUNIT_EXPECT_KASAN_FAIL(test
, *(volatile char *)p
);
705 /* Check that ksize() makes the whole object accessible. */
706 static void ksize_unpoisons_memory(struct kunit
*test
)
709 size_t size
= 123, real_size
;
711 ptr
= kmalloc(size
, GFP_KERNEL
);
712 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
713 real_size
= ksize(ptr
);
715 /* This access shouldn't trigger a KASAN report. */
719 KUNIT_EXPECT_KASAN_FAIL(test
, ((volatile char *)ptr
)[real_size
]);
725 * Check that a use-after-free is detected by ksize() and via normal accesses
728 static void ksize_uaf(struct kunit
*test
)
731 int size
= 128 - KASAN_GRANULE_SIZE
;
733 ptr
= kmalloc(size
, GFP_KERNEL
);
734 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
737 KUNIT_EXPECT_KASAN_FAIL(test
, ksize(ptr
));
738 KUNIT_EXPECT_KASAN_FAIL(test
, ((volatile char *)ptr
)[0]);
739 KUNIT_EXPECT_KASAN_FAIL(test
, ((volatile char *)ptr
)[size
]);
742 static void kasan_stack_oob(struct kunit
*test
)
744 char stack_array
[10];
745 /* See comment in kasan_global_oob. */
746 char *volatile array
= stack_array
;
747 char *p
= &array
[ARRAY_SIZE(stack_array
) + OOB_TAG_OFF
];
749 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_STACK
);
751 KUNIT_EXPECT_KASAN_FAIL(test
, *(volatile char *)p
);
754 static void kasan_alloca_oob_left(struct kunit
*test
)
757 char alloca_array
[i
];
758 /* See comment in kasan_global_oob. */
759 char *volatile array
= alloca_array
;
762 /* Only generic mode instruments dynamic allocas. */
763 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_GENERIC
);
764 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_STACK
);
766 KUNIT_EXPECT_KASAN_FAIL(test
, *(volatile char *)p
);
769 static void kasan_alloca_oob_right(struct kunit
*test
)
772 char alloca_array
[i
];
773 /* See comment in kasan_global_oob. */
774 char *volatile array
= alloca_array
;
777 /* Only generic mode instruments dynamic allocas. */
778 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_GENERIC
);
779 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_STACK
);
781 KUNIT_EXPECT_KASAN_FAIL(test
, *(volatile char *)p
);
784 static void kmem_cache_double_free(struct kunit
*test
)
788 struct kmem_cache
*cache
;
790 cache
= kmem_cache_create("test_cache", size
, 0, 0, NULL
);
791 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, cache
);
793 p
= kmem_cache_alloc(cache
, GFP_KERNEL
);
795 kunit_err(test
, "Allocation failed: %s\n", __func__
);
796 kmem_cache_destroy(cache
);
800 kmem_cache_free(cache
, p
);
801 KUNIT_EXPECT_KASAN_FAIL(test
, kmem_cache_free(cache
, p
));
802 kmem_cache_destroy(cache
);
805 static void kmem_cache_invalid_free(struct kunit
*test
)
809 struct kmem_cache
*cache
;
811 cache
= kmem_cache_create("test_cache", size
, 0, SLAB_TYPESAFE_BY_RCU
,
813 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, cache
);
815 p
= kmem_cache_alloc(cache
, GFP_KERNEL
);
817 kunit_err(test
, "Allocation failed: %s\n", __func__
);
818 kmem_cache_destroy(cache
);
822 /* Trigger invalid free, the object doesn't get freed. */
823 KUNIT_EXPECT_KASAN_FAIL(test
, kmem_cache_free(cache
, p
+ 1));
826 * Properly free the object to prevent the "Objects remaining in
827 * test_cache on __kmem_cache_shutdown" BUG failure.
829 kmem_cache_free(cache
, p
);
831 kmem_cache_destroy(cache
);
834 static void kasan_memchr(struct kunit
*test
)
840 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT.
841 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details.
843 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_AMD_MEM_ENCRYPT
);
846 size
= round_up(size
, OOB_TAG_OFF
);
848 ptr
= kmalloc(size
, GFP_KERNEL
| __GFP_ZERO
);
849 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
851 KUNIT_EXPECT_KASAN_FAIL(test
,
852 kasan_ptr_result
= memchr(ptr
, '1', size
+ 1));
857 static void kasan_memcmp(struct kunit
*test
)
864 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT.
865 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details.
867 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_AMD_MEM_ENCRYPT
);
870 size
= round_up(size
, OOB_TAG_OFF
);
872 ptr
= kmalloc(size
, GFP_KERNEL
| __GFP_ZERO
);
873 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
874 memset(arr
, 0, sizeof(arr
));
876 KUNIT_EXPECT_KASAN_FAIL(test
,
877 kasan_int_result
= memcmp(ptr
, arr
, size
+1));
881 static void kasan_strings(struct kunit
*test
)
887 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT.
888 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details.
890 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_AMD_MEM_ENCRYPT
);
892 ptr
= kmalloc(size
, GFP_KERNEL
| __GFP_ZERO
);
893 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
898 * Try to cause only 1 invalid access (less spam in dmesg).
899 * For that we need ptr to point to zeroed byte.
900 * Skip metadata that could be stored in freed object so ptr
901 * will likely point to zeroed byte.
904 KUNIT_EXPECT_KASAN_FAIL(test
, kasan_ptr_result
= strchr(ptr
, '1'));
906 KUNIT_EXPECT_KASAN_FAIL(test
, kasan_ptr_result
= strrchr(ptr
, '1'));
908 KUNIT_EXPECT_KASAN_FAIL(test
, kasan_int_result
= strcmp(ptr
, "2"));
910 KUNIT_EXPECT_KASAN_FAIL(test
, kasan_int_result
= strncmp(ptr
, "2", 1));
912 KUNIT_EXPECT_KASAN_FAIL(test
, kasan_int_result
= strlen(ptr
));
914 KUNIT_EXPECT_KASAN_FAIL(test
, kasan_int_result
= strnlen(ptr
, 1));
917 static void kasan_bitops_modify(struct kunit
*test
, int nr
, void *addr
)
919 KUNIT_EXPECT_KASAN_FAIL(test
, set_bit(nr
, addr
));
920 KUNIT_EXPECT_KASAN_FAIL(test
, __set_bit(nr
, addr
));
921 KUNIT_EXPECT_KASAN_FAIL(test
, clear_bit(nr
, addr
));
922 KUNIT_EXPECT_KASAN_FAIL(test
, __clear_bit(nr
, addr
));
923 KUNIT_EXPECT_KASAN_FAIL(test
, clear_bit_unlock(nr
, addr
));
924 KUNIT_EXPECT_KASAN_FAIL(test
, __clear_bit_unlock(nr
, addr
));
925 KUNIT_EXPECT_KASAN_FAIL(test
, change_bit(nr
, addr
));
926 KUNIT_EXPECT_KASAN_FAIL(test
, __change_bit(nr
, addr
));
929 static void kasan_bitops_test_and_modify(struct kunit
*test
, int nr
, void *addr
)
931 KUNIT_EXPECT_KASAN_FAIL(test
, test_and_set_bit(nr
, addr
));
932 KUNIT_EXPECT_KASAN_FAIL(test
, __test_and_set_bit(nr
, addr
));
933 KUNIT_EXPECT_KASAN_FAIL(test
, test_and_set_bit_lock(nr
, addr
));
934 KUNIT_EXPECT_KASAN_FAIL(test
, test_and_clear_bit(nr
, addr
));
935 KUNIT_EXPECT_KASAN_FAIL(test
, __test_and_clear_bit(nr
, addr
));
936 KUNIT_EXPECT_KASAN_FAIL(test
, test_and_change_bit(nr
, addr
));
937 KUNIT_EXPECT_KASAN_FAIL(test
, __test_and_change_bit(nr
, addr
));
938 KUNIT_EXPECT_KASAN_FAIL(test
, kasan_int_result
= test_bit(nr
, addr
));
940 #if defined(clear_bit_unlock_is_negative_byte)
941 KUNIT_EXPECT_KASAN_FAIL(test
, kasan_int_result
=
942 clear_bit_unlock_is_negative_byte(nr
, addr
));
946 static void kasan_bitops_generic(struct kunit
*test
)
950 /* This test is specifically crafted for the generic mode. */
951 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_GENERIC
);
954 * Allocate 1 more byte, which causes kzalloc to round up to 16 bytes;
955 * this way we do not actually corrupt other memory.
957 bits
= kzalloc(sizeof(*bits
) + 1, GFP_KERNEL
);
958 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, bits
);
961 * Below calls try to access bit within allocated memory; however, the
962 * below accesses are still out-of-bounds, since bitops are defined to
963 * operate on the whole long the bit is in.
965 kasan_bitops_modify(test
, BITS_PER_LONG
, bits
);
968 * Below calls try to access bit beyond allocated memory.
970 kasan_bitops_test_and_modify(test
, BITS_PER_LONG
+ BITS_PER_BYTE
, bits
);
975 static void kasan_bitops_tags(struct kunit
*test
)
979 /* This test is specifically crafted for tag-based modes. */
980 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_KASAN_GENERIC
);
982 /* kmalloc-64 cache will be used and the last 16 bytes will be the redzone. */
983 bits
= kzalloc(48, GFP_KERNEL
);
984 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, bits
);
986 /* Do the accesses past the 48 allocated bytes, but within the redone. */
987 kasan_bitops_modify(test
, BITS_PER_LONG
, (void *)bits
+ 48);
988 kasan_bitops_test_and_modify(test
, BITS_PER_LONG
+ BITS_PER_BYTE
, (void *)bits
+ 48);
993 static void kmalloc_double_kzfree(struct kunit
*test
)
998 ptr
= kmalloc(size
, GFP_KERNEL
);
999 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
1001 kfree_sensitive(ptr
);
1002 KUNIT_EXPECT_KASAN_FAIL(test
, kfree_sensitive(ptr
));
1005 static void vmalloc_oob(struct kunit
*test
)
1009 KASAN_TEST_NEEDS_CONFIG_ON(test
, CONFIG_KASAN_VMALLOC
);
1012 * We have to be careful not to hit the guard page.
1013 * The MMU will catch that and crash us.
1015 area
= vmalloc(3000);
1016 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, area
);
1018 KUNIT_EXPECT_KASAN_FAIL(test
, ((volatile char *)area
)[3100]);
1023 * Check that the assigned pointer tag falls within the [KASAN_TAG_MIN,
1024 * KASAN_TAG_KERNEL) range (note: excluding the match-all tag) for tag-based
1027 static void match_all_not_assigned(struct kunit
*test
)
1033 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_KASAN_GENERIC
);
1035 for (i
= 0; i
< 256; i
++) {
1036 size
= (get_random_int() % 1024) + 1;
1037 ptr
= kmalloc(size
, GFP_KERNEL
);
1038 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
1039 KUNIT_EXPECT_GE(test
, (u8
)get_tag(ptr
), (u8
)KASAN_TAG_MIN
);
1040 KUNIT_EXPECT_LT(test
, (u8
)get_tag(ptr
), (u8
)KASAN_TAG_KERNEL
);
1044 for (i
= 0; i
< 256; i
++) {
1045 order
= (get_random_int() % 4) + 1;
1046 pages
= alloc_pages(GFP_KERNEL
, order
);
1047 ptr
= page_address(pages
);
1048 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
1049 KUNIT_EXPECT_GE(test
, (u8
)get_tag(ptr
), (u8
)KASAN_TAG_MIN
);
1050 KUNIT_EXPECT_LT(test
, (u8
)get_tag(ptr
), (u8
)KASAN_TAG_KERNEL
);
1051 free_pages((unsigned long)ptr
, order
);
1055 /* Check that 0xff works as a match-all pointer tag for tag-based modes. */
1056 static void match_all_ptr_tag(struct kunit
*test
)
1061 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_KASAN_GENERIC
);
1063 ptr
= kmalloc(128, GFP_KERNEL
);
1064 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
1066 /* Backup the assigned tag. */
1068 KUNIT_EXPECT_NE(test
, tag
, (u8
)KASAN_TAG_KERNEL
);
1070 /* Reset the tag to 0xff.*/
1071 ptr
= set_tag(ptr
, KASAN_TAG_KERNEL
);
1073 /* This access shouldn't trigger a KASAN report. */
1076 /* Recover the pointer tag and free. */
1077 ptr
= set_tag(ptr
, tag
);
1081 /* Check that there are no match-all memory tags for tag-based modes. */
1082 static void match_all_mem_tag(struct kunit
*test
)
1087 KASAN_TEST_NEEDS_CONFIG_OFF(test
, CONFIG_KASAN_GENERIC
);
1089 ptr
= kmalloc(128, GFP_KERNEL
);
1090 KUNIT_ASSERT_NOT_ERR_OR_NULL(test
, ptr
);
1091 KUNIT_EXPECT_NE(test
, (u8
)get_tag(ptr
), (u8
)KASAN_TAG_KERNEL
);
1093 /* For each possible tag value not matching the pointer tag. */
1094 for (tag
= KASAN_TAG_MIN
; tag
<= KASAN_TAG_KERNEL
; tag
++) {
1095 if (tag
== get_tag(ptr
))
1098 /* Mark the first memory granule with the chosen memory tag. */
1099 kasan_poison(ptr
, KASAN_GRANULE_SIZE
, (u8
)tag
, false);
1101 /* This access must cause a KASAN report. */
1102 KUNIT_EXPECT_KASAN_FAIL(test
, *ptr
= 0);
1105 /* Recover the memory tag and free. */
1106 kasan_poison(ptr
, KASAN_GRANULE_SIZE
, get_tag(ptr
), false);
1110 static struct kunit_case kasan_kunit_test_cases
[] = {
1111 KUNIT_CASE(kmalloc_oob_right
),
1112 KUNIT_CASE(kmalloc_oob_left
),
1113 KUNIT_CASE(kmalloc_node_oob_right
),
1114 KUNIT_CASE(kmalloc_pagealloc_oob_right
),
1115 KUNIT_CASE(kmalloc_pagealloc_uaf
),
1116 KUNIT_CASE(kmalloc_pagealloc_invalid_free
),
1117 KUNIT_CASE(pagealloc_oob_right
),
1118 KUNIT_CASE(pagealloc_uaf
),
1119 KUNIT_CASE(kmalloc_large_oob_right
),
1120 KUNIT_CASE(krealloc_more_oob
),
1121 KUNIT_CASE(krealloc_less_oob
),
1122 KUNIT_CASE(krealloc_pagealloc_more_oob
),
1123 KUNIT_CASE(krealloc_pagealloc_less_oob
),
1124 KUNIT_CASE(krealloc_uaf
),
1125 KUNIT_CASE(kmalloc_oob_16
),
1126 KUNIT_CASE(kmalloc_uaf_16
),
1127 KUNIT_CASE(kmalloc_oob_in_memset
),
1128 KUNIT_CASE(kmalloc_oob_memset_2
),
1129 KUNIT_CASE(kmalloc_oob_memset_4
),
1130 KUNIT_CASE(kmalloc_oob_memset_8
),
1131 KUNIT_CASE(kmalloc_oob_memset_16
),
1132 KUNIT_CASE(kmalloc_memmove_invalid_size
),
1133 KUNIT_CASE(kmalloc_uaf
),
1134 KUNIT_CASE(kmalloc_uaf_memset
),
1135 KUNIT_CASE(kmalloc_uaf2
),
1136 KUNIT_CASE(kfree_via_page
),
1137 KUNIT_CASE(kfree_via_phys
),
1138 KUNIT_CASE(kmem_cache_oob
),
1139 KUNIT_CASE(kmem_cache_accounted
),
1140 KUNIT_CASE(kmem_cache_bulk
),
1141 KUNIT_CASE(kasan_global_oob
),
1142 KUNIT_CASE(kasan_stack_oob
),
1143 KUNIT_CASE(kasan_alloca_oob_left
),
1144 KUNIT_CASE(kasan_alloca_oob_right
),
1145 KUNIT_CASE(ksize_unpoisons_memory
),
1146 KUNIT_CASE(ksize_uaf
),
1147 KUNIT_CASE(kmem_cache_double_free
),
1148 KUNIT_CASE(kmem_cache_invalid_free
),
1149 KUNIT_CASE(kasan_memchr
),
1150 KUNIT_CASE(kasan_memcmp
),
1151 KUNIT_CASE(kasan_strings
),
1152 KUNIT_CASE(kasan_bitops_generic
),
1153 KUNIT_CASE(kasan_bitops_tags
),
1154 KUNIT_CASE(kmalloc_double_kzfree
),
1155 KUNIT_CASE(vmalloc_oob
),
1156 KUNIT_CASE(match_all_not_assigned
),
1157 KUNIT_CASE(match_all_ptr_tag
),
1158 KUNIT_CASE(match_all_mem_tag
),
1162 static struct kunit_suite kasan_kunit_test_suite
= {
1164 .init
= kasan_test_init
,
1165 .test_cases
= kasan_kunit_test_cases
,
1166 .exit
= kasan_test_exit
,
1169 kunit_test_suite(kasan_kunit_test_suite
);
1171 MODULE_LICENSE("GPL");