1 //===-- sanitizer_wrappers.cpp ----------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Redirect some functions to sanitizer interceptors.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include <dlfcn.h>
14 #include <errno.h>
15 #include <fcntl.h>
16 #include <inttypes.h>
17 #include <stdarg.h>
18 #include <stdio.h>
19 #include <unistd.h>
20
21 #include <tuple>
22
23 namespace __sanitizer {
24 unsigned long internal_open(const char *filename, int flags);
25 unsigned long internal_open(const char *filename, int flags, unsigned mode);
26 unsigned long internal_close(int fd);
27 unsigned long internal_stat(const char *path, void *buf);
28 unsigned long internal_lstat(const char *path, void *buf);
29 unsigned long internal_fstat(int fd, void *buf);
30 size_t internal_strlen(const char *s);
31 unsigned long internal_mmap(void *addr, uintptr_t length, int prot, int flags,
32 int fd, unsigned long long offset);
33 void *internal_memcpy(void *dest, const void *src, unsigned long n);
34 // Used to propagate errno.
35 bool internal_iserror(uintptr_t retval, int *rverrno = 0);
36 } // namespace __sanitizer
37
38 namespace {
39
40 template <typename T>
41 struct GetTypes;
42
43 template <typename R, typename... Args>
44 struct GetTypes<R(Args...)> {
45 using Result = R;
46 template <size_t i>
47 struct Arg {
48 using Type = typename std::tuple_element<i, std::tuple<Args...>>::type;
49 };
50 };
51
52 #define LLVM_SYMBOLIZER_GET_FUNC(Function) \
53 ((__interceptor_##Function) \
54 ? (__interceptor_##Function) \
55 : reinterpret_cast<decltype(&Function)>(dlsym(RTLD_NEXT, #Function)))
56
57 #define LLVM_SYMBOLIZER_INTERCEPTOR1(Function, ...) \
58 GetTypes<__VA_ARGS__>::Result __interceptor_##Function( \
59 GetTypes<__VA_ARGS__>::Arg<0>::Type) __attribute__((weak)); \
60 GetTypes<__VA_ARGS__>::Result Function( \
61 GetTypes<__VA_ARGS__>::Arg<0>::Type arg0) { \
62 return LLVM_SYMBOLIZER_GET_FUNC(Function)(arg0); \
63 }
64
65 #define LLVM_SYMBOLIZER_INTERCEPTOR2(Function, ...) \
66 GetTypes<__VA_ARGS__>::Result __interceptor_##Function( \
67 GetTypes<__VA_ARGS__>::Arg<0>::Type, \
68 GetTypes<__VA_ARGS__>::Arg<1>::Type) __attribute__((weak)); \
69 GetTypes<__VA_ARGS__>::Result Function( \
70 GetTypes<__VA_ARGS__>::Arg<0>::Type arg0, \
71 GetTypes<__VA_ARGS__>::Arg<1>::Type arg1) { \
72 return LLVM_SYMBOLIZER_GET_FUNC(Function)(arg0, arg1); \
73 }
74
75 #define LLVM_SYMBOLIZER_INTERCEPTOR3(Function, ...) \
76 GetTypes<__VA_ARGS__>::Result __interceptor_##Function( \
77 GetTypes<__VA_ARGS__>::Arg<0>::Type, \
78 GetTypes<__VA_ARGS__>::Arg<1>::Type, \
79 GetTypes<__VA_ARGS__>::Arg<2>::Type) __attribute__((weak)); \
80 GetTypes<__VA_ARGS__>::Result Function( \
81 GetTypes<__VA_ARGS__>::Arg<0>::Type arg0, \
82 GetTypes<__VA_ARGS__>::Arg<1>::Type arg1, \
83 GetTypes<__VA_ARGS__>::Arg<2>::Type arg2) { \
84 return LLVM_SYMBOLIZER_GET_FUNC(Function)(arg0, arg1, arg2); \
85 }
86
87 #define LLVM_SYMBOLIZER_INTERCEPTOR4(Function, ...) \
88 GetTypes<__VA_ARGS__>::Result __interceptor_##Function( \
89 GetTypes<__VA_ARGS__>::Arg<0>::Type, \
90 GetTypes<__VA_ARGS__>::Arg<1>::Type, \
91 GetTypes<__VA_ARGS__>::Arg<2>::Type, \
92 GetTypes<__VA_ARGS__>::Arg<3>::Type) __attribute__((weak)); \
93 GetTypes<__VA_ARGS__>::Result Function( \
94 GetTypes<__VA_ARGS__>::Arg<0>::Type arg0, \
95 GetTypes<__VA_ARGS__>::Arg<1>::Type arg1, \
96 GetTypes<__VA_ARGS__>::Arg<2>::Type arg2, \
97 GetTypes<__VA_ARGS__>::Arg<3>::Type arg3) { \
98 return LLVM_SYMBOLIZER_GET_FUNC(Function)(arg0, arg1, arg2, arg3); \
99 }
100
101 } // namespace
102
103 // C-style interface around internal sanitizer libc functions.
104 extern "C" {
105
106 #define RETURN_OR_SET_ERRNO(T, res) \
107 int rverrno; \
108 if (__sanitizer::internal_iserror(res, &rverrno)) { \
109 errno = rverrno; \
110 return (T)-1; \
111 } \
112 return (T)res;
113
open(const char * filename,int flags,...)114 int open(const char *filename, int flags, ...) {
115 unsigned long res;
116 if (flags | O_CREAT) {
117 va_list va;
118 va_start(va, flags);
119 unsigned mode = va_arg(va, unsigned);
120 va_end(va);
121 res = __sanitizer::internal_open(filename, flags, mode);
122 } else {
123 res = __sanitizer::internal_open(filename, flags);
124 }
125 RETURN_OR_SET_ERRNO(int, res);
126 }
127
close(int fd)128 int close(int fd) {
129 unsigned long res = __sanitizer::internal_close(fd);
130 RETURN_OR_SET_ERRNO(int, res);
131 }
132
133 #define STAT(func, arg, buf) \
134 unsigned long res = __sanitizer::internal_##func(arg, buf); \
135 RETURN_OR_SET_ERRNO(int, res);
136
stat(const char * path,struct stat * buf)137 int stat(const char *path, struct stat *buf) { STAT(stat, path, buf); }
138
lstat(const char * path,struct stat * buf)139 int lstat(const char *path, struct stat *buf) { STAT(lstat, path, buf); }
140
fstat(int fd,struct stat * buf)141 int fstat(int fd, struct stat *buf) { STAT(fstat, fd, buf); }
142
143 // Redirect versioned stat functions to the __sanitizer::internal() as well.
__xstat(int version,const char * path,struct stat * buf)144 int __xstat(int version, const char *path, struct stat *buf) {
145 STAT(stat, path, buf);
146 }
147
__lxstat(int version,const char * path,struct stat * buf)148 int __lxstat(int version, const char *path, struct stat *buf) {
149 STAT(lstat, path, buf);
150 }
151
__fxstat(int version,int fd,struct stat * buf)152 int __fxstat(int version, int fd, struct stat *buf) { STAT(fstat, fd, buf); }
153
strlen(const char * s)154 size_t strlen(const char *s) { return __sanitizer::internal_strlen(s); }
155
mmap(void * addr,size_t length,int prot,int flags,int fd,off_t offset)156 void *mmap(void *addr, size_t length, int prot, int flags, int fd,
157 off_t offset) {
158 unsigned long res =
159 __sanitizer::internal_mmap(addr, length, prot, flags, fd, offset);
160 RETURN_OR_SET_ERRNO(void *, res);
161 }
162
163 LLVM_SYMBOLIZER_INTERCEPTOR3(read, ssize_t(int, void *, size_t))
164 LLVM_SYMBOLIZER_INTERCEPTOR4(pread, ssize_t(int, void *, size_t, off_t))
165 LLVM_SYMBOLIZER_INTERCEPTOR4(pread64, ssize_t(int, void *, size_t, off64_t))
166 LLVM_SYMBOLIZER_INTERCEPTOR2(realpath, char *(const char *, char *))
167
168 LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_cond_broadcast, int(pthread_cond_t *))
169 LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_cond_wait,
170 int(pthread_cond_t *, pthread_mutex_t *))
171 LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutex_lock, int(pthread_mutex_t *))
172 LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutex_unlock, int(pthread_mutex_t *))
173 LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutex_destroy, int(pthread_mutex_t *))
174 LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_mutex_init,
175 int(pthread_mutex_t *,
176 const pthread_mutexattr_t *))
177 LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutexattr_destroy,
178 int(pthread_mutexattr_t *))
179 LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutexattr_init, int(pthread_mutexattr_t *))
180 LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_mutexattr_settype,
181 int(pthread_mutexattr_t *, int))
182 LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_getspecific, void *(pthread_key_t))
183 LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_key_create,
184 int(pthread_key_t *, void (*)(void *)))
185 LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_once,
186 int(pthread_once_t *, void (*)(void)))
187 LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_setspecific,
188 int(pthread_key_t, const void *))
189 LLVM_SYMBOLIZER_INTERCEPTOR3(pthread_sigmask,
190 int(int, const sigset_t *, sigset_t *))
191
192 } // extern "C"
193