1 /*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <dlfcn.h>
18 #include <gtest/gtest.h>
19 #include <sys/stat.h>
20
21 #include "BionicDeathTest.h"
22 #include "gtest_globals.h"
23 #include "utils.h"
24
25 #if defined(__BIONIC__)
26 #include "private/CFIShadow.h"
27 #endif
28
29 // Private libdl interface.
30 extern "C" {
31 void __cfi_slowpath(uint64_t CallSiteTypeId, void* Ptr);
32 void __cfi_slowpath_diag(uint64_t CallSiteTypeId, void* Ptr, void* DiagData);
33 size_t __cfi_shadow_size();
34 }
35
f()36 static void f() {}
37
TEST(cfi_test,basic)38 TEST(cfi_test, basic) {
39 #if defined(__BIONIC__)
40 void* handle;
41 handle = dlopen("libcfi-test.so", RTLD_NOW | RTLD_LOCAL);
42 ASSERT_TRUE(handle != nullptr) << dlerror();
43
44 EXPECT_NE(0U, __cfi_shadow_size());
45
46 #define SYM(type, name) auto name = reinterpret_cast<type>(dlsym(handle, #name))
47 SYM(size_t (*)(), get_count);
48 SYM(uint64_t(*)(), get_last_type_id);
49 SYM(void* (*)(), get_last_address);
50 SYM(void* (*)(), get_last_diag);
51 SYM(void* (*)(), get_global_address);
52 SYM(void (*)(uint64_t, void*, void*), __cfi_check);
53 SYM(char*, bss);
54 #undef SYM
55
56 size_t c = get_count();
57
58 // CFI check for code inside the DSO. Can't use just any function address - this is only
59 // guaranteed to work for code addresses above __cfi_check.
60 void* code_ptr = reinterpret_cast<char*>(__cfi_check) + 1234;
61 void* diag_ptr = reinterpret_cast<void*>(5678);
62 __cfi_slowpath_diag(42, code_ptr, diag_ptr);
63 EXPECT_EQ(42U, get_last_type_id());
64 EXPECT_EQ(code_ptr, get_last_address());
65 EXPECT_EQ(diag_ptr, get_last_diag());
66 EXPECT_EQ(++c, get_count());
67
68 // __cfi_slowpath passes nullptr for the Diag argument.
69 __cfi_slowpath(42, code_ptr);
70 EXPECT_EQ(42U, get_last_type_id());
71 EXPECT_EQ(code_ptr, get_last_address());
72 EXPECT_EQ(nullptr, get_last_diag());
73 EXPECT_EQ(++c, get_count());
74
75 // CFI check for a data address inside the DSO.
76 __cfi_slowpath(43, get_global_address());
77 EXPECT_EQ(43U, get_last_type_id());
78 EXPECT_EQ(get_global_address(), get_last_address());
79 EXPECT_EQ(++c, get_count());
80
81 // CFI check for a function inside _this_ DSO. It either goes to this DSO's __cfi_check,
82 // or (if missing) is simply ignored. Any way, it does not affect the test lib's counters.
83 __cfi_slowpath(44, reinterpret_cast<void*>(&f));
84 EXPECT_EQ(43U, get_last_type_id());
85 EXPECT_EQ(get_global_address(), get_last_address());
86 EXPECT_EQ(c, get_count());
87
88 // CFI check for a stack address. This is always invalid and gets the process killed.
89 EXPECT_DEATH(__cfi_slowpath(45, reinterpret_cast<void*>(&c)), "");
90
91 // CFI check for a heap address. This is always invalid and gets the process killed.
92 void* p = malloc(4096);
93 EXPECT_DEATH(__cfi_slowpath(46, p), "");
94 free(p);
95
96 // Check all the addresses.
97 const size_t bss_size = 1024 * 1024;
98 static_assert(bss_size >= kLibraryAlignment * 2, "test range not big enough");
99 for (size_t i = 0; i < bss_size; ++i) {
100 __cfi_slowpath(47, bss + i);
101 EXPECT_EQ(++c, get_count());
102 }
103
104 // Load the same library again.
105 void* handle2 = dlopen("libcfi-test.so", RTLD_NOW | RTLD_LOCAL);
106 ASSERT_TRUE(handle2 != nullptr) << dlerror();
107 EXPECT_EQ(handle2, handle);
108
109 // Check that it is still there.
110 __cfi_slowpath(43, get_global_address());
111 EXPECT_EQ(43U, get_last_type_id());
112 EXPECT_EQ(get_global_address(), get_last_address());
113 EXPECT_EQ(++c, get_count());
114
115 dlclose(handle);
116 dlclose(handle2);
117
118 // CFI check for a function inside the unloaded DSO. This is always invalid and gets the process
119 // killed.
120 EXPECT_DEATH(__cfi_slowpath(45, reinterpret_cast<void*>(code_ptr)), "");
121 #endif
122 }
123
TEST(cfi_test,invalid)124 TEST(cfi_test, invalid) {
125 #if defined(__BIONIC__)
126 void* handle;
127 handle = dlopen("libcfi-test-bad.so", RTLD_NOW | RTLD_LOCAL);
128 ASSERT_FALSE(handle != nullptr) << dlerror();
129
130 handle = dlopen("libcfi-test-bad.so", RTLD_NOW | RTLD_LOCAL);
131 ASSERT_FALSE(handle != nullptr) << dlerror();
132 #endif
133 }
134
135 // cfi_test_helper exports __cfi_check, which triggers CFI initialization at startup.
TEST(cfi_test,early_init)136 TEST(cfi_test, early_init) {
137 #if defined(__BIONIC__)
138 std::string helper = GetTestlibRoot() + "/cfi_test_helper/cfi_test_helper";
139 chmod(helper.c_str(), 0755); // TODO: "x" lost in CTS, b/34945607
140 ExecTestHelper eth;
141 eth.SetArgs({ helper.c_str(), nullptr });
142 eth.Run([&]() { execve(helper.c_str(), eth.GetArgs(), eth.GetEnv()); }, 0, nullptr);
143 #endif
144 }
145
146 // cfi_test_helper2 depends on a library that exports __cfi_check, which triggers CFI initialization
147 // at startup.
TEST(cfi_test,early_init2)148 TEST(cfi_test, early_init2) {
149 #if defined(__BIONIC__)
150 std::string helper = GetTestlibRoot() + "/cfi_test_helper2/cfi_test_helper2";
151 chmod(helper.c_str(), 0755); // TODO: "x" lost in CTS, b/34945607
152 ExecTestHelper eth;
153 eth.SetArgs({ helper.c_str(), nullptr });
154 eth.Run([&]() { execve(helper.c_str(), eth.GetArgs(), eth.GetEnv()); }, 0, nullptr);
155 #endif
156 }
157