]>
git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blob - lib/test_kasan.c
3 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
4 * Author: Andrey Ryabinin <a.ryabinin@samsung.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
12 #define pr_fmt(fmt) "kasan test: %s " fmt, __func__
14 #include <linux/delay.h>
15 #include <linux/kernel.h>
16 #include <linux/mman.h>
18 #include <linux/printk.h>
19 #include <linux/slab.h>
20 #include <linux/string.h>
21 #include <linux/uaccess.h>
22 #include <linux/module.h>
23 #include <linux/kasan.h>
26 * Note: test functions are marked noinline so that their names appear in
30 static noinline
void __init
kmalloc_oob_right(void)
35 pr_info("out-of-bounds to right\n");
36 ptr
= kmalloc(size
, GFP_KERNEL
);
38 pr_err("Allocation failed\n");
46 static noinline
void __init
kmalloc_oob_left(void)
51 pr_info("out-of-bounds to left\n");
52 ptr
= kmalloc(size
, GFP_KERNEL
);
54 pr_err("Allocation failed\n");
62 static noinline
void __init
kmalloc_node_oob_right(void)
67 pr_info("kmalloc_node(): out-of-bounds to right\n");
68 ptr
= kmalloc_node(size
, GFP_KERNEL
, 0);
70 pr_err("Allocation failed\n");
79 static noinline
void __init
kmalloc_pagealloc_oob_right(void)
82 size_t size
= KMALLOC_MAX_CACHE_SIZE
+ 10;
84 /* Allocate a chunk that does not fit into a SLUB cache to trigger
85 * the page allocator fallback.
87 pr_info("kmalloc pagealloc allocation: out-of-bounds to right\n");
88 ptr
= kmalloc(size
, GFP_KERNEL
);
90 pr_err("Allocation failed\n");
98 static noinline
void __init
kmalloc_pagealloc_uaf(void)
101 size_t size
= KMALLOC_MAX_CACHE_SIZE
+ 10;
103 pr_info("kmalloc pagealloc allocation: use-after-free\n");
104 ptr
= kmalloc(size
, GFP_KERNEL
);
106 pr_err("Allocation failed\n");
114 static noinline
void __init
kmalloc_pagealloc_invalid_free(void)
117 size_t size
= KMALLOC_MAX_CACHE_SIZE
+ 10;
119 pr_info("kmalloc pagealloc allocation: invalid-free\n");
120 ptr
= kmalloc(size
, GFP_KERNEL
);
122 pr_err("Allocation failed\n");
130 static noinline
void __init
kmalloc_large_oob_right(void)
133 size_t size
= KMALLOC_MAX_CACHE_SIZE
- 256;
134 /* Allocate a chunk that is large enough, but still fits into a slab
135 * and does not trigger the page allocator fallback in SLUB.
137 pr_info("kmalloc large allocation: out-of-bounds to right\n");
138 ptr
= kmalloc(size
, GFP_KERNEL
);
140 pr_err("Allocation failed\n");
148 static noinline
void __init
kmalloc_oob_krealloc_more(void)
154 pr_info("out-of-bounds after krealloc more\n");
155 ptr1
= kmalloc(size1
, GFP_KERNEL
);
156 ptr2
= krealloc(ptr1
, size2
, GFP_KERNEL
);
157 if (!ptr1
|| !ptr2
) {
158 pr_err("Allocation failed\n");
167 static noinline
void __init
kmalloc_oob_krealloc_less(void)
173 pr_info("out-of-bounds after krealloc less\n");
174 ptr1
= kmalloc(size1
, GFP_KERNEL
);
175 ptr2
= krealloc(ptr1
, size2
, GFP_KERNEL
);
176 if (!ptr1
|| !ptr2
) {
177 pr_err("Allocation failed\n");
185 static noinline
void __init
kmalloc_oob_16(void)
191 pr_info("kmalloc out-of-bounds for 16-bytes access\n");
192 ptr1
= kmalloc(sizeof(*ptr1
) - 3, GFP_KERNEL
);
193 ptr2
= kmalloc(sizeof(*ptr2
), GFP_KERNEL
);
194 if (!ptr1
|| !ptr2
) {
195 pr_err("Allocation failed\n");
205 static noinline
void __init
kmalloc_oob_memset_2(void)
210 pr_info("out-of-bounds in memset2\n");
211 ptr
= kmalloc(size
, GFP_KERNEL
);
213 pr_err("Allocation failed\n");
221 static noinline
void __init
kmalloc_oob_memset_4(void)
226 pr_info("out-of-bounds in memset4\n");
227 ptr
= kmalloc(size
, GFP_KERNEL
);
229 pr_err("Allocation failed\n");
238 static noinline
void __init
kmalloc_oob_memset_8(void)
243 pr_info("out-of-bounds in memset8\n");
244 ptr
= kmalloc(size
, GFP_KERNEL
);
246 pr_err("Allocation failed\n");
254 static noinline
void __init
kmalloc_oob_memset_16(void)
259 pr_info("out-of-bounds in memset16\n");
260 ptr
= kmalloc(size
, GFP_KERNEL
);
262 pr_err("Allocation failed\n");
266 memset(ptr
+1, 0, 16);
270 static noinline
void __init
kmalloc_oob_in_memset(void)
275 pr_info("out-of-bounds in memset\n");
276 ptr
= kmalloc(size
, GFP_KERNEL
);
278 pr_err("Allocation failed\n");
282 memset(ptr
, 0, size
+5);
286 static noinline
void __init
kmalloc_uaf(void)
291 pr_info("use-after-free\n");
292 ptr
= kmalloc(size
, GFP_KERNEL
);
294 pr_err("Allocation failed\n");
302 static noinline
void __init
kmalloc_uaf_memset(void)
307 pr_info("use-after-free in memset\n");
308 ptr
= kmalloc(size
, GFP_KERNEL
);
310 pr_err("Allocation failed\n");
315 memset(ptr
, 0, size
);
318 static noinline
void __init
kmalloc_uaf2(void)
323 pr_info("use-after-free after another kmalloc\n");
324 ptr1
= kmalloc(size
, GFP_KERNEL
);
326 pr_err("Allocation failed\n");
331 ptr2
= kmalloc(size
, GFP_KERNEL
);
333 pr_err("Allocation failed\n");
339 pr_err("Could not detect use-after-free: ptr1 == ptr2\n");
343 static noinline
void __init
kmem_cache_oob(void)
347 struct kmem_cache
*cache
= kmem_cache_create("test_cache",
351 pr_err("Cache allocation failed\n");
354 pr_info("out-of-bounds in kmem_cache_alloc\n");
355 p
= kmem_cache_alloc(cache
, GFP_KERNEL
);
357 pr_err("Allocation failed\n");
358 kmem_cache_destroy(cache
);
363 kmem_cache_free(cache
, p
);
364 kmem_cache_destroy(cache
);
367 static noinline
void __init
memcg_accounted_kmem_cache(void)
372 struct kmem_cache
*cache
;
374 cache
= kmem_cache_create("test_cache", size
, 0, SLAB_ACCOUNT
, NULL
);
376 pr_err("Cache allocation failed\n");
380 pr_info("allocate memcg accounted object\n");
382 * Several allocations with a delay to allow for lazy per memcg kmem
385 for (i
= 0; i
< 5; i
++) {
386 p
= kmem_cache_alloc(cache
, GFP_KERNEL
);
390 kmem_cache_free(cache
, p
);
395 kmem_cache_destroy(cache
);
398 static char global_array
[10];
400 static noinline
void __init
kasan_global_oob(void)
403 char *p
= &global_array
[ARRAY_SIZE(global_array
) + i
];
405 pr_info("out-of-bounds global variable\n");
409 static noinline
void __init
kasan_stack_oob(void)
411 char stack_array
[10];
413 char *p
= &stack_array
[ARRAY_SIZE(stack_array
) + i
];
415 pr_info("out-of-bounds on stack\n");
419 static noinline
void __init
ksize_unpoisons_memory(void)
422 size_t size
= 123, real_size
;
424 pr_info("ksize() unpoisons the whole allocated chunk\n");
425 ptr
= kmalloc(size
, GFP_KERNEL
);
427 pr_err("Allocation failed\n");
430 real_size
= ksize(ptr
);
431 /* This access doesn't trigger an error. */
434 ptr
[real_size
] = 'y';
438 static noinline
void __init
copy_user_test(void)
441 char __user
*usermem
;
445 kmem
= kmalloc(size
, GFP_KERNEL
);
449 usermem
= (char __user
*)vm_mmap(NULL
, 0, PAGE_SIZE
,
450 PROT_READ
| PROT_WRITE
| PROT_EXEC
,
451 MAP_ANONYMOUS
| MAP_PRIVATE
, 0);
452 if (IS_ERR(usermem
)) {
453 pr_err("Failed to allocate user memory\n");
458 pr_info("out-of-bounds in copy_from_user()\n");
459 unused
= copy_from_user(kmem
, usermem
, size
+ 1);
461 pr_info("out-of-bounds in copy_to_user()\n");
462 unused
= copy_to_user(usermem
, kmem
, size
+ 1);
464 pr_info("out-of-bounds in __copy_from_user()\n");
465 unused
= __copy_from_user(kmem
, usermem
, size
+ 1);
467 pr_info("out-of-bounds in __copy_to_user()\n");
468 unused
= __copy_to_user(usermem
, kmem
, size
+ 1);
470 pr_info("out-of-bounds in __copy_from_user_inatomic()\n");
471 unused
= __copy_from_user_inatomic(kmem
, usermem
, size
+ 1);
473 pr_info("out-of-bounds in __copy_to_user_inatomic()\n");
474 unused
= __copy_to_user_inatomic(usermem
, kmem
, size
+ 1);
476 pr_info("out-of-bounds in strncpy_from_user()\n");
477 unused
= strncpy_from_user(kmem
, usermem
, size
+ 1);
479 vm_munmap((unsigned long)usermem
, PAGE_SIZE
);
483 static noinline
void __init
kasan_alloca_oob_left(void)
486 char alloca_array
[i
];
487 char *p
= alloca_array
- 1;
489 pr_info("out-of-bounds to left on alloca\n");
493 static noinline
void __init
kasan_alloca_oob_right(void)
496 char alloca_array
[i
];
497 char *p
= alloca_array
+ i
;
499 pr_info("out-of-bounds to right on alloca\n");
503 static noinline
void __init
kmem_cache_double_free(void)
507 struct kmem_cache
*cache
;
509 cache
= kmem_cache_create("test_cache", size
, 0, 0, NULL
);
511 pr_err("Cache allocation failed\n");
514 pr_info("double-free on heap object\n");
515 p
= kmem_cache_alloc(cache
, GFP_KERNEL
);
517 pr_err("Allocation failed\n");
518 kmem_cache_destroy(cache
);
522 kmem_cache_free(cache
, p
);
523 kmem_cache_free(cache
, p
);
524 kmem_cache_destroy(cache
);
527 static noinline
void __init
kmem_cache_invalid_free(void)
531 struct kmem_cache
*cache
;
533 cache
= kmem_cache_create("test_cache", size
, 0, SLAB_TYPESAFE_BY_RCU
,
536 pr_err("Cache allocation failed\n");
539 pr_info("invalid-free of heap object\n");
540 p
= kmem_cache_alloc(cache
, GFP_KERNEL
);
542 pr_err("Allocation failed\n");
543 kmem_cache_destroy(cache
);
547 /* Trigger invalid free, the object doesn't get freed */
548 kmem_cache_free(cache
, p
+ 1);
551 * Properly free the object to prevent the "Objects remaining in
552 * test_cache on __kmem_cache_shutdown" BUG failure.
554 kmem_cache_free(cache
, p
);
556 kmem_cache_destroy(cache
);
559 static noinline
void __init
kasan_memchr(void)
564 pr_info("out-of-bounds in memchr\n");
565 ptr
= kmalloc(size
, GFP_KERNEL
| __GFP_ZERO
);
569 memchr(ptr
, '1', size
+ 1);
573 static noinline
void __init
kasan_memcmp(void)
579 pr_info("out-of-bounds in memcmp\n");
580 ptr
= kmalloc(size
, GFP_KERNEL
| __GFP_ZERO
);
584 memset(arr
, 0, sizeof(arr
));
585 memcmp(ptr
, arr
, size
+1);
589 static noinline
void __init
kasan_strings(void)
594 pr_info("use-after-free in strchr\n");
595 ptr
= kmalloc(size
, GFP_KERNEL
| __GFP_ZERO
);
602 * Try to cause only 1 invalid access (less spam in dmesg).
603 * For that we need ptr to point to zeroed byte.
604 * Skip metadata that could be stored in freed object so ptr
605 * will likely point to zeroed byte.
610 pr_info("use-after-free in strrchr\n");
613 pr_info("use-after-free in strcmp\n");
616 pr_info("use-after-free in strncmp\n");
617 strncmp(ptr
, "2", 1);
619 pr_info("use-after-free in strlen\n");
622 pr_info("use-after-free in strnlen\n");
626 static int __init
kmalloc_tests_init(void)
629 * Temporarily enable multi-shot mode. Otherwise, we'd only get a
630 * report for the first case.
632 bool multishot
= kasan_save_enable_multi_shot();
636 kmalloc_node_oob_right();
638 kmalloc_pagealloc_oob_right();
639 kmalloc_pagealloc_uaf();
640 kmalloc_pagealloc_invalid_free();
642 kmalloc_large_oob_right();
643 kmalloc_oob_krealloc_more();
644 kmalloc_oob_krealloc_less();
646 kmalloc_oob_in_memset();
647 kmalloc_oob_memset_2();
648 kmalloc_oob_memset_4();
649 kmalloc_oob_memset_8();
650 kmalloc_oob_memset_16();
652 kmalloc_uaf_memset();
655 memcg_accounted_kmem_cache();
658 kasan_alloca_oob_left();
659 kasan_alloca_oob_right();
660 ksize_unpoisons_memory();
662 kmem_cache_double_free();
663 kmem_cache_invalid_free();
668 kasan_restore_multi_shot(multishot
);
673 module_init(kmalloc_tests_init
);
674 MODULE_LICENSE("GPL");