blob: 098c08eddfab715e98a0c428ef69f3012b58d5d0 [file] [log] [blame]
Andrey Ryabinin3f158012015-02-13 14:39:53 -08001/*
2 *
3 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
4 * Author: Andrey Ryabinin <a.ryabinin@samsung.com>
5 *
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.
9 *
10 */
11
12#define pr_fmt(fmt) "kasan test: %s " fmt, __func__
13
14#include <linux/kernel.h>
15#include <linux/printk.h>
16#include <linux/slab.h>
17#include <linux/string.h>
18#include <linux/module.h>
19
20static noinline void __init kmalloc_oob_right(void)
21{
22 char *ptr;
23 size_t size = 123;
24
25 pr_info("out-of-bounds to right\n");
26 ptr = kmalloc(size, GFP_KERNEL);
27 if (!ptr) {
28 pr_err("Allocation failed\n");
29 return;
30 }
31
32 ptr[size] = 'x';
33 kfree(ptr);
34}
35
36static noinline void __init kmalloc_oob_left(void)
37{
38 char *ptr;
39 size_t size = 15;
40
41 pr_info("out-of-bounds to left\n");
42 ptr = kmalloc(size, GFP_KERNEL);
43 if (!ptr) {
44 pr_err("Allocation failed\n");
45 return;
46 }
47
48 *ptr = *(ptr - 1);
49 kfree(ptr);
50}
51
52static noinline void __init kmalloc_node_oob_right(void)
53{
54 char *ptr;
55 size_t size = 4096;
56
57 pr_info("kmalloc_node(): out-of-bounds to right\n");
58 ptr = kmalloc_node(size, GFP_KERNEL, 0);
59 if (!ptr) {
60 pr_err("Allocation failed\n");
61 return;
62 }
63
64 ptr[size] = 0;
65 kfree(ptr);
66}
67
68static noinline void __init kmalloc_large_oob_rigth(void)
69{
70 char *ptr;
71 size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
72
73 pr_info("kmalloc large allocation: out-of-bounds to right\n");
74 ptr = kmalloc(size, GFP_KERNEL);
75 if (!ptr) {
76 pr_err("Allocation failed\n");
77 return;
78 }
79
80 ptr[size] = 0;
81 kfree(ptr);
82}
83
84static noinline void __init kmalloc_oob_krealloc_more(void)
85{
86 char *ptr1, *ptr2;
87 size_t size1 = 17;
88 size_t size2 = 19;
89
90 pr_info("out-of-bounds after krealloc more\n");
91 ptr1 = kmalloc(size1, GFP_KERNEL);
92 ptr2 = krealloc(ptr1, size2, GFP_KERNEL);
93 if (!ptr1 || !ptr2) {
94 pr_err("Allocation failed\n");
95 kfree(ptr1);
96 return;
97 }
98
99 ptr2[size2] = 'x';
100 kfree(ptr2);
101}
102
103static noinline void __init kmalloc_oob_krealloc_less(void)
104{
105 char *ptr1, *ptr2;
106 size_t size1 = 17;
107 size_t size2 = 15;
108
109 pr_info("out-of-bounds after krealloc less\n");
110 ptr1 = kmalloc(size1, GFP_KERNEL);
111 ptr2 = krealloc(ptr1, size2, GFP_KERNEL);
112 if (!ptr1 || !ptr2) {
113 pr_err("Allocation failed\n");
114 kfree(ptr1);
115 return;
116 }
117 ptr2[size1] = 'x';
118 kfree(ptr2);
119}
120
121static noinline void __init kmalloc_oob_16(void)
122{
123 struct {
124 u64 words[2];
125 } *ptr1, *ptr2;
126
127 pr_info("kmalloc out-of-bounds for 16-bytes access\n");
128 ptr1 = kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL);
129 ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL);
130 if (!ptr1 || !ptr2) {
131 pr_err("Allocation failed\n");
132 kfree(ptr1);
133 kfree(ptr2);
134 return;
135 }
136 *ptr1 = *ptr2;
137 kfree(ptr1);
138 kfree(ptr2);
139}
140
141static noinline void __init kmalloc_oob_in_memset(void)
142{
143 char *ptr;
144 size_t size = 666;
145
146 pr_info("out-of-bounds in memset\n");
147 ptr = kmalloc(size, GFP_KERNEL);
148 if (!ptr) {
149 pr_err("Allocation failed\n");
150 return;
151 }
152
153 memset(ptr, 0, size+5);
154 kfree(ptr);
155}
156
157static noinline void __init kmalloc_uaf(void)
158{
159 char *ptr;
160 size_t size = 10;
161
162 pr_info("use-after-free\n");
163 ptr = kmalloc(size, GFP_KERNEL);
164 if (!ptr) {
165 pr_err("Allocation failed\n");
166 return;
167 }
168
169 kfree(ptr);
170 *(ptr + 8) = 'x';
171}
172
173static noinline void __init kmalloc_uaf_memset(void)
174{
175 char *ptr;
176 size_t size = 33;
177
178 pr_info("use-after-free in memset\n");
179 ptr = kmalloc(size, GFP_KERNEL);
180 if (!ptr) {
181 pr_err("Allocation failed\n");
182 return;
183 }
184
185 kfree(ptr);
186 memset(ptr, 0, size);
187}
188
189static noinline void __init kmalloc_uaf2(void)
190{
191 char *ptr1, *ptr2;
192 size_t size = 43;
193
194 pr_info("use-after-free after another kmalloc\n");
195 ptr1 = kmalloc(size, GFP_KERNEL);
196 if (!ptr1) {
197 pr_err("Allocation failed\n");
198 return;
199 }
200
201 kfree(ptr1);
202 ptr2 = kmalloc(size, GFP_KERNEL);
203 if (!ptr2) {
204 pr_err("Allocation failed\n");
205 return;
206 }
207
208 ptr1[40] = 'x';
209 kfree(ptr2);
210}
211
212static noinline void __init kmem_cache_oob(void)
213{
214 char *p;
215 size_t size = 200;
216 struct kmem_cache *cache = kmem_cache_create("test_cache",
217 size, 0,
218 0, NULL);
219 if (!cache) {
220 pr_err("Cache allocation failed\n");
221 return;
222 }
223 pr_info("out-of-bounds in kmem_cache_alloc\n");
224 p = kmem_cache_alloc(cache, GFP_KERNEL);
225 if (!p) {
226 pr_err("Allocation failed\n");
227 kmem_cache_destroy(cache);
228 return;
229 }
230
231 *p = p[size];
232 kmem_cache_free(cache, p);
233 kmem_cache_destroy(cache);
234}
235
236static char global_array[10];
237
238static noinline void __init kasan_global_oob(void)
239{
240 volatile int i = 3;
241 char *p = &global_array[ARRAY_SIZE(global_array) + i];
242
243 pr_info("out-of-bounds global variable\n");
244 *(volatile char *)p;
245}
246
247static noinline void __init kasan_stack_oob(void)
248{
249 char stack_array[10];
250 volatile int i = 0;
251 char *p = &stack_array[ARRAY_SIZE(stack_array) + i];
252
253 pr_info("out-of-bounds on stack\n");
254 *(volatile char *)p;
255}
256
257static int __init kmalloc_tests_init(void)
258{
259 kmalloc_oob_right();
260 kmalloc_oob_left();
261 kmalloc_node_oob_right();
262 kmalloc_large_oob_rigth();
263 kmalloc_oob_krealloc_more();
264 kmalloc_oob_krealloc_less();
265 kmalloc_oob_16();
266 kmalloc_oob_in_memset();
267 kmalloc_uaf();
268 kmalloc_uaf_memset();
269 kmalloc_uaf2();
270 kmem_cache_oob();
271 kasan_stack_oob();
272 kasan_global_oob();
273 return -EAGAIN;
274}
275
276module_init(kmalloc_tests_init);
277MODULE_LICENSE("GPL");