1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 *
4 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
5 * Author: Andrey Ryabinin <a.ryabinin@samsung.com>
6 */
7
8 #define pr_fmt(fmt) "kasan: test: " fmt
9
10 #include <linux/mman.h>
11 #include <linux/module.h>
12 #include <linux/printk.h>
13 #include <linux/slab.h>
14 #include <linux/uaccess.h>
15
16 #include "kasan.h"
17
18 static noinline void __init copy_user_test(void)
19 {
20 char *kmem;
21 char __user *usermem;
22 size_t size = 128 - KASAN_GRANULE_SIZE;
23 int __maybe_unused unused;
24
25 kmem = kmalloc(size, GFP_KERNEL);
26 if (!kmem)
27 return;
28
29 usermem = (char __user *)vm_mmap(NULL, 0, PAGE_SIZE,
30 PROT_READ | PROT_WRITE | PROT_EXEC,
31 MAP_ANONYMOUS | MAP_PRIVATE, 0);
32 if (IS_ERR(usermem)) {
33 pr_err("Failed to allocate user memory\n");
34 kfree(kmem);
35 return;
36 }
37
38 OPTIMIZER_HIDE_VAR(size);
39
40 pr_info("out-of-bounds in copy_from_user()\n");
41 unused = copy_from_user(kmem, usermem, size + 1);
42
43 pr_info("out-of-bounds in copy_to_user()\n");
44 unused = copy_to_user(usermem, kmem, size + 1);
45
46 pr_info("out-of-bounds in __copy_from_user()\n");
47 unused = __copy_from_user(kmem, usermem, size + 1);
48
49 pr_info("out-of-bounds in __copy_to_user()\n");
50 unused = __copy_to_user(usermem, kmem, size + 1);
51
52 pr_info("out-of-bounds in __copy_from_user_inatomic()\n");
53 unused = __copy_from_user_inatomic(kmem, usermem, size + 1);
54
55 pr_info("out-of-bounds in __copy_to_user_inatomic()\n");
56 unused = __copy_to_user_inatomic(usermem, kmem, size + 1);
57
58 pr_info("out-of-bounds in strncpy_from_user()\n");
59 unused = strncpy_from_user(kmem, usermem, size + 1);
60
61 vm_munmap((unsigned long)usermem, PAGE_SIZE);
62 kfree(kmem);
63 }
64
65 static int __init kasan_test_module_init(void)
66 {
67 /*
68 * Temporarily enable multi-shot mode. Otherwise, KASAN would only
69 * report the first detected bug and panic the kernel if panic_on_warn
70 * is enabled.
71 */
72 bool multishot = kasan_save_enable_multi_shot();
73
74 copy_user_test();
75
76 kasan_restore_multi_shot(multishot);
77 return -EAGAIN;
78 }
79
80 module_init(kasan_test_module_init);
81 MODULE_LICENSE("GPL");
82
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