drm/amdgpu: set adev->num_vmhubs for gmc6,7,8
[linux-2.6-block.git] / lib / test_user_copy.c
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9c92ab61 1// SPDX-License-Identifier: GPL-2.0-only
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2/*
3 * Kernel module for testing copy_to/from_user infrastructure.
4 *
5 * Copyright 2013 Google Inc. All Rights Reserved
6 *
7 * Authors:
8 * Kees Cook <keescook@chromium.org>
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9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/mman.h>
14#include <linux/module.h>
15#include <linux/sched.h>
16#include <linux/slab.h>
17#include <linux/uaccess.h>
18#include <linux/vmalloc.h>
19
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20/*
21 * Several 32-bit architectures support 64-bit {get,put}_user() calls.
22 * As there doesn't appear to be anything that can safely determine
23 * their capability at compile-time, we just have to opt-out certain archs.
24 */
4deaa6fd 25#if BITS_PER_LONG == 64 || (!(defined(CONFIG_ARM) && !defined(MMU)) && \
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26 !defined(CONFIG_M68K) && \
27 !defined(CONFIG_MICROBLAZE) && \
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28 !defined(CONFIG_NIOS2) && \
29 !defined(CONFIG_PPC32) && \
30 !defined(CONFIG_SUPERH))
31# define TEST_U64
32#endif
33
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34#define test(condition, msg) \
35({ \
36 int cond = (condition); \
37 if (cond) \
38 pr_warn("%s\n", msg); \
39 cond; \
40})
41
42static int __init test_user_copy_init(void)
43{
44 int ret = 0;
45 char *kmem;
46 char __user *usermem;
47 char *bad_usermem;
48 unsigned long user_addr;
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49 u8 val_u8;
50 u16 val_u16;
51 u32 val_u32;
52#ifdef TEST_U64
53 u64 val_u64;
54#endif
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55
56 kmem = kmalloc(PAGE_SIZE * 2, GFP_KERNEL);
57 if (!kmem)
58 return -ENOMEM;
59
60 user_addr = vm_mmap(NULL, 0, PAGE_SIZE * 2,
61 PROT_READ | PROT_WRITE | PROT_EXEC,
62 MAP_ANONYMOUS | MAP_PRIVATE, 0);
63 if (user_addr >= (unsigned long)(TASK_SIZE)) {
64 pr_warn("Failed to allocate user memory\n");
65 kfree(kmem);
66 return -ENOMEM;
67 }
68
69 usermem = (char __user *)user_addr;
70 bad_usermem = (char *)user_addr;
71
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72 /*
73 * Legitimate usage: none of these copies should fail.
74 */
4c5d7bc6 75 memset(kmem, 0x3a, PAGE_SIZE * 2);
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76 ret |= test(copy_to_user(usermem, kmem, PAGE_SIZE),
77 "legitimate copy_to_user failed");
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78 memset(kmem, 0x0, PAGE_SIZE);
79 ret |= test(copy_from_user(kmem, usermem, PAGE_SIZE),
80 "legitimate copy_from_user failed");
81 ret |= test(memcmp(kmem, kmem + PAGE_SIZE, PAGE_SIZE),
82 "legitimate usercopy failed to copy data");
83
84#define test_legit(size, check) \
85 do { \
86 val_##size = check; \
87 ret |= test(put_user(val_##size, (size __user *)usermem), \
88 "legitimate put_user (" #size ") failed"); \
89 val_##size = 0; \
90 ret |= test(get_user(val_##size, (size __user *)usermem), \
91 "legitimate get_user (" #size ") failed"); \
92 ret |= test(val_##size != check, \
93 "legitimate get_user (" #size ") failed to do copy"); \
94 if (val_##size != check) { \
95 pr_info("0x%llx != 0x%llx\n", \
96 (unsigned long long)val_##size, \
97 (unsigned long long)check); \
98 } \
99 } while (0)
100
101 test_legit(u8, 0x5a);
102 test_legit(u16, 0x5a5b);
103 test_legit(u32, 0x5a5b5c5d);
104#ifdef TEST_U64
105 test_legit(u64, 0x5a5b5c5d6a6b6c6d);
106#endif
107#undef test_legit
3e2a4c18 108
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109 /*
110 * Invalid usage: none of these copies should succeed.
111 */
112
113 /* Prepare kernel memory with check values. */
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114 memset(kmem, 0x5a, PAGE_SIZE);
115 memset(kmem + PAGE_SIZE, 0, PAGE_SIZE);
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116
117 /* Reject kernel-to-kernel copies through copy_from_user(). */
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118 ret |= test(!copy_from_user(kmem, (char __user *)(kmem + PAGE_SIZE),
119 PAGE_SIZE),
120 "illegal all-kernel copy_from_user passed");
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121
122 /* Destination half of buffer should have been zeroed. */
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123 ret |= test(memcmp(kmem + PAGE_SIZE, kmem, PAGE_SIZE),
124 "zeroing failure for illegal all-kernel copy_from_user");
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125
126#if 0
127 /*
128 * When running with SMAP/PAN/etc, this will Oops the kernel
129 * due to the zeroing of userspace memory on failure. This needs
130 * to be tested in LKDTM instead, since this test module does not
131 * expect to explode.
132 */
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133 ret |= test(!copy_from_user(bad_usermem, (char __user *)kmem,
134 PAGE_SIZE),
135 "illegal reversed copy_from_user passed");
f5f893c5 136#endif
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137 ret |= test(!copy_to_user((char __user *)kmem, kmem + PAGE_SIZE,
138 PAGE_SIZE),
139 "illegal all-kernel copy_to_user passed");
140 ret |= test(!copy_to_user((char __user *)kmem, bad_usermem,
141 PAGE_SIZE),
142 "illegal reversed copy_to_user passed");
f5f893c5 143
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144#define test_illegal(size, check) \
145 do { \
146 val_##size = (check); \
147 ret |= test(!get_user(val_##size, (size __user *)kmem), \
148 "illegal get_user (" #size ") passed"); \
149 ret |= test(val_##size != (size)0, \
150 "zeroing failure for illegal get_user (" #size ")"); \
151 if (val_##size != (size)0) { \
152 pr_info("0x%llx != 0\n", \
153 (unsigned long long)val_##size); \
154 } \
155 ret |= test(!put_user(val_##size, (size __user *)kmem), \
156 "illegal put_user (" #size ") passed"); \
157 } while (0)
158
159 test_illegal(u8, 0x5a);
160 test_illegal(u16, 0x5a5b);
161 test_illegal(u32, 0x5a5b5c5d);
162#ifdef TEST_U64
163 test_illegal(u64, 0x5a5b5c5d6a6b6c6d);
164#endif
165#undef test_illegal
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166
167 vm_munmap(user_addr, PAGE_SIZE * 2);
168 kfree(kmem);
169
170 if (ret == 0) {
171 pr_info("tests passed.\n");
172 return 0;
173 }
174
175 return -EINVAL;
176}
177
178module_init(test_user_copy_init);
179
180static void __exit test_user_copy_exit(void)
181{
182 pr_info("unloaded.\n");
183}
184
185module_exit(test_user_copy_exit);
186
187MODULE_AUTHOR("Kees Cook <keescook@chromium.org>");
188MODULE_LICENSE("GPL");