cfi_test.cpp revision beb3eb1790dffc6e2f57a670aec89364944f66c4 
1#include <gtest/gtest.h>
2#include <dlfcn.h>
3
4#include "BionicDeathTest.h"
5
6// Private libdl interface.
7extern "C" {
8void __cfi_slowpath(uint64_t CallSiteTypeId, void* Ptr);
9void __cfi_slowpath_diag(uint64_t CallSiteTypeId, void* Ptr, void* DiagData);
10}
11
12static void f() {}
13
14TEST(cfi_test, basic) {
15  void* handle;
16  handle = dlopen("libcfi-test.so", RTLD_NOW | RTLD_LOCAL);
17  ASSERT_TRUE(handle != nullptr) << dlerror();
18
19#define SYM(type, name) auto name = reinterpret_cast<type>(dlsym(handle, #name))
20  SYM(int (*)(), get_count);
21  SYM(uint64_t(*)(), get_last_type_id);
22  SYM(void* (*)(), get_last_address);
23  SYM(void* (*)(), get_last_diag);
24  SYM(void* (*)(), get_global_address);
25  SYM(void (*)(uint64_t, void*, void*), __cfi_check);
26#undef SYM
27
28  int c = get_count();
29
30  // CFI check for code inside the DSO. Can't use just any function address - this is only
31  // guaranteed to work for code addresses above __cfi_check.
32  void* code_ptr = reinterpret_cast<char*>(__cfi_check) + 1234;
33  void* diag_ptr = reinterpret_cast<void*>(5678);
34  __cfi_slowpath_diag(42, code_ptr, diag_ptr);
35  EXPECT_EQ(42U, get_last_type_id());
36  EXPECT_EQ(code_ptr, get_last_address());
37  EXPECT_EQ(diag_ptr, get_last_diag());
38  EXPECT_EQ(++c, get_count());
39
40  // __cfi_slowpath passes nullptr for the Diag argument.
41  __cfi_slowpath(42, code_ptr);
42  EXPECT_EQ(42U, get_last_type_id());
43  EXPECT_EQ(code_ptr, get_last_address());
44  EXPECT_EQ(nullptr, get_last_diag());
45  EXPECT_EQ(++c, get_count());
46
47  // CFI check for a data address inside the DSO.
48  __cfi_slowpath(43, get_global_address());
49  EXPECT_EQ(43U, get_last_type_id());
50  EXPECT_EQ(get_global_address(), get_last_address());
51  EXPECT_EQ(++c, get_count());
52
53  // CFI check for a function inside _this_ DSO. It either goes to this DSO's __cfi_check,
54  // or (if missing) is simply ignored. Any way, it does not affect the test lib's counters.
55  __cfi_slowpath(44, reinterpret_cast<void*>(&f));
56  EXPECT_EQ(43U, get_last_type_id());
57  EXPECT_EQ(get_global_address(), get_last_address());
58  EXPECT_EQ(c, get_count());
59
60  // CFI check for a stack address. This is always invalid and gets the process killed.
61  EXPECT_DEATH(__cfi_slowpath(45, reinterpret_cast<void*>(&c)), "");
62
63  // CFI check for a heap address. This is always invalid and gets the process killed.
64  void* p = malloc(4096);
65  EXPECT_DEATH(__cfi_slowpath(46, p), "");
66  free(p);
67
68  // Load the same library again.
69  void* handle2 = dlopen("libcfi-test.so", RTLD_NOW | RTLD_LOCAL);
70  ASSERT_TRUE(handle2 != nullptr) << dlerror();
71  EXPECT_EQ(handle2, handle);
72
73  // Check that it is still there.
74  __cfi_slowpath(43, get_global_address());
75  EXPECT_EQ(43U, get_last_type_id());
76  EXPECT_EQ(get_global_address(), get_last_address());
77  EXPECT_EQ(++c, get_count());
78
79  dlclose(handle);
80  dlclose(handle2);
81
82  // CFI check for a function inside the unloaded DSO. This is always invalid and gets the process
83  // killed.
84  EXPECT_DEATH(__cfi_slowpath(45, reinterpret_cast<void*>(code_ptr)), "");
85}
86
87TEST(cfi_test, invalid) {
88  void* handle;
89  handle = dlopen("libcfi-test-bad.so", RTLD_NOW | RTLD_LOCAL);
90  ASSERT_FALSE(handle != nullptr) << dlerror();
91
92  handle = dlopen("libcfi-test-bad.so", RTLD_NOW | RTLD_LOCAL);
93  ASSERT_FALSE(handle != nullptr) << dlerror();
94}
95