1 //===-- memprof_interceptors.cpp -----------------------------------------===// 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 // This file is a part of MemProfiler, a memory profiler. 10 // 11 // Intercept various libc functions. 12 //===----------------------------------------------------------------------===// 13 14 #include "memprof_interceptors.h" 15 #include "memprof_allocator.h" 16 #include "memprof_internal.h" 17 #include "memprof_mapping.h" 18 #include "memprof_stack.h" 19 #include "memprof_stats.h" 20 #include "sanitizer_common/sanitizer_libc.h" 21 #include "sanitizer_common/sanitizer_posix.h" 22 23 namespace __memprof { 24 25 #define MEMPROF_READ_STRING(s, n) MEMPROF_READ_RANGE((s), (n)) 26 27 static inline uptr MaybeRealStrnlen(const char *s, uptr maxlen) { 28 #if SANITIZER_INTERCEPT_STRNLEN 29 if (REAL(strnlen)) { 30 return REAL(strnlen)(s, maxlen); 31 } 32 #endif 33 return internal_strnlen(s, maxlen); 34 } 35 36 void SetThreadName(const char *name) { 37 MemprofThread *t = GetCurrentThread(); 38 if (t) 39 memprofThreadRegistry().SetThreadName(t->tid(), name); 40 } 41 42 int OnExit() { 43 // FIXME: ask frontend whether we need to return failure. 44 return 0; 45 } 46 47 } // namespace __memprof 48 49 // ---------------------- Wrappers ---------------- {{{1 50 using namespace __memprof; 51 52 DECLARE_REAL_AND_INTERCEPTOR(void *, malloc, uptr) 53 DECLARE_REAL_AND_INTERCEPTOR(void, free, void *) 54 55 #define COMMON_INTERCEPT_FUNCTION_VER(name, ver) \ 56 MEMPROF_INTERCEPT_FUNC_VER(name, ver) 57 #define COMMON_INTERCEPT_FUNCTION_VER_UNVERSIONED_FALLBACK(name, ver) \ 58 MEMPROF_INTERCEPT_FUNC_VER_UNVERSIONED_FALLBACK(name, ver) 59 #define COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ptr, size) \ 60 MEMPROF_WRITE_RANGE(ptr, size) 61 #define COMMON_INTERCEPTOR_READ_RANGE(ctx, ptr, size) \ 62 MEMPROF_READ_RANGE(ptr, size) 63 #define COMMON_INTERCEPTOR_ENTER(ctx, func, ...) \ 64 MEMPROF_INTERCEPTOR_ENTER(ctx, func); \ 65 do { \ 66 if (memprof_init_is_running) \ 67 return REAL(func)(__VA_ARGS__); \ 68 ENSURE_MEMPROF_INITED(); \ 69 } while (false) 70 #define COMMON_INTERCEPTOR_DIR_ACQUIRE(ctx, path) \ 71 do { \ 72 } while (false) 73 #define COMMON_INTERCEPTOR_FD_ACQUIRE(ctx, fd) \ 74 do { \ 75 } while (false) 76 #define COMMON_INTERCEPTOR_FD_RELEASE(ctx, fd) \ 77 do { \ 78 } while (false) 79 #define COMMON_INTERCEPTOR_FD_SOCKET_ACCEPT(ctx, fd, newfd) \ 80 do { \ 81 } while (false) 82 #define COMMON_INTERCEPTOR_SET_THREAD_NAME(ctx, name) SetThreadName(name) 83 // Should be memprofThreadRegistry().SetThreadNameByUserId(thread, name) 84 // But memprof does not remember UserId's for threads (pthread_t); 85 // and remembers all ever existed threads, so the linear search by UserId 86 // can be slow. 87 #define COMMON_INTERCEPTOR_SET_PTHREAD_NAME(ctx, thread, name) \ 88 do { \ 89 } while (false) 90 #define COMMON_INTERCEPTOR_BLOCK_REAL(name) REAL(name) 91 #define COMMON_INTERCEPTOR_ON_EXIT(ctx) OnExit() 92 #define COMMON_INTERCEPTOR_LIBRARY_LOADED(filename, handle) 93 #define COMMON_INTERCEPTOR_LIBRARY_UNLOADED() 94 #define COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED (!memprof_inited) 95 #define COMMON_INTERCEPTOR_GET_TLS_RANGE(begin, end) \ 96 if (MemprofThread *t = GetCurrentThread()) { \ 97 *begin = t->tls_begin(); \ 98 *end = t->tls_end(); \ 99 } else { \ 100 *begin = *end = 0; \ 101 } 102 103 #include "sanitizer_common/sanitizer_common_interceptors.inc" 104 105 #define COMMON_SYSCALL_PRE_READ_RANGE(p, s) MEMPROF_READ_RANGE(p, s) 106 #define COMMON_SYSCALL_PRE_WRITE_RANGE(p, s) MEMPROF_WRITE_RANGE(p, s) 107 #define COMMON_SYSCALL_POST_READ_RANGE(p, s) \ 108 do { \ 109 (void)(p); \ 110 (void)(s); \ 111 } while (false) 112 #define COMMON_SYSCALL_POST_WRITE_RANGE(p, s) \ 113 do { \ 114 (void)(p); \ 115 (void)(s); \ 116 } while (false) 117 #include "sanitizer_common/sanitizer_common_syscalls.inc" 118 119 struct ThreadStartParam { 120 atomic_uintptr_t t; 121 atomic_uintptr_t is_registered; 122 }; 123 124 static thread_return_t THREAD_CALLING_CONV memprof_thread_start(void *arg) { 125 ThreadStartParam *param = reinterpret_cast<ThreadStartParam *>(arg); 126 MemprofThread *t = nullptr; 127 while ((t = reinterpret_cast<MemprofThread *>( 128 atomic_load(¶m->t, memory_order_acquire))) == nullptr) 129 internal_sched_yield(); 130 SetCurrentThread(t); 131 return t->ThreadStart(GetTid(), ¶m->is_registered); 132 } 133 134 INTERCEPTOR(int, pthread_create, void *thread, void *attr, 135 void *(*start_routine)(void *), void *arg) { 136 EnsureMainThreadIDIsCorrect(); 137 GET_STACK_TRACE_THREAD; 138 int detached = 0; 139 if (attr) 140 REAL(pthread_attr_getdetachstate)(attr, &detached); 141 ThreadStartParam param; 142 atomic_store(¶m.t, 0, memory_order_relaxed); 143 atomic_store(¶m.is_registered, 0, memory_order_relaxed); 144 int result; 145 { 146 // Ignore all allocations made by pthread_create: thread stack/TLS may be 147 // stored by pthread for future reuse even after thread destruction, and 148 // the linked list it's stored in doesn't even hold valid pointers to the 149 // objects, the latter are calculated by obscure pointer arithmetic. 150 result = REAL(pthread_create)(thread, attr, memprof_thread_start, ¶m); 151 } 152 if (result == 0) { 153 u32 current_tid = GetCurrentTidOrInvalid(); 154 MemprofThread *t = MemprofThread::Create(start_routine, arg, current_tid, 155 &stack, detached); 156 atomic_store(¶m.t, reinterpret_cast<uptr>(t), memory_order_release); 157 // Wait until the MemprofThread object is initialized and the 158 // ThreadRegistry entry is in "started" state. 159 while (atomic_load(¶m.is_registered, memory_order_acquire) == 0) 160 internal_sched_yield(); 161 } 162 return result; 163 } 164 165 INTERCEPTOR(int, pthread_join, void *t, void **arg) { 166 return real_pthread_join(t, arg); 167 } 168 169 DEFINE_REAL_PTHREAD_FUNCTIONS 170 171 INTERCEPTOR(char *, index, const char *string, int c) 172 ALIAS(WRAP(strchr)); 173 174 // For both strcat() and strncat() we need to check the validity of |to| 175 // argument irrespective of the |from| length. 176 INTERCEPTOR(char *, strcat, char *to, const char *from) { 177 void *ctx; 178 MEMPROF_INTERCEPTOR_ENTER(ctx, strcat); 179 ENSURE_MEMPROF_INITED(); 180 uptr from_length = internal_strlen(from); 181 MEMPROF_READ_RANGE(from, from_length + 1); 182 uptr to_length = internal_strlen(to); 183 MEMPROF_READ_STRING(to, to_length); 184 MEMPROF_WRITE_RANGE(to + to_length, from_length + 1); 185 return REAL(strcat)(to, from); 186 } 187 188 INTERCEPTOR(char *, strncat, char *to, const char *from, uptr size) { 189 void *ctx; 190 MEMPROF_INTERCEPTOR_ENTER(ctx, strncat); 191 ENSURE_MEMPROF_INITED(); 192 uptr from_length = MaybeRealStrnlen(from, size); 193 uptr copy_length = Min(size, from_length + 1); 194 MEMPROF_READ_RANGE(from, copy_length); 195 uptr to_length = internal_strlen(to); 196 MEMPROF_READ_STRING(to, to_length); 197 MEMPROF_WRITE_RANGE(to + to_length, from_length + 1); 198 return REAL(strncat)(to, from, size); 199 } 200 201 INTERCEPTOR(char *, strcpy, char *to, const char *from) { 202 void *ctx; 203 MEMPROF_INTERCEPTOR_ENTER(ctx, strcpy); 204 if (memprof_init_is_running) { 205 return REAL(strcpy)(to, from); 206 } 207 ENSURE_MEMPROF_INITED(); 208 uptr from_size = internal_strlen(from) + 1; 209 MEMPROF_READ_RANGE(from, from_size); 210 MEMPROF_WRITE_RANGE(to, from_size); 211 return REAL(strcpy)(to, from); 212 } 213 214 INTERCEPTOR(char *, strdup, const char *s) { 215 void *ctx; 216 MEMPROF_INTERCEPTOR_ENTER(ctx, strdup); 217 if (UNLIKELY(!memprof_inited)) 218 return internal_strdup(s); 219 ENSURE_MEMPROF_INITED(); 220 uptr length = internal_strlen(s); 221 MEMPROF_READ_RANGE(s, length + 1); 222 GET_STACK_TRACE_MALLOC; 223 void *new_mem = memprof_malloc(length + 1, &stack); 224 REAL(memcpy)(new_mem, s, length + 1); 225 return reinterpret_cast<char *>(new_mem); 226 } 227 228 INTERCEPTOR(char *, __strdup, const char *s) { 229 void *ctx; 230 MEMPROF_INTERCEPTOR_ENTER(ctx, strdup); 231 if (UNLIKELY(!memprof_inited)) 232 return internal_strdup(s); 233 ENSURE_MEMPROF_INITED(); 234 uptr length = internal_strlen(s); 235 MEMPROF_READ_RANGE(s, length + 1); 236 GET_STACK_TRACE_MALLOC; 237 void *new_mem = memprof_malloc(length + 1, &stack); 238 REAL(memcpy)(new_mem, s, length + 1); 239 return reinterpret_cast<char *>(new_mem); 240 } 241 242 INTERCEPTOR(char *, strncpy, char *to, const char *from, uptr size) { 243 void *ctx; 244 MEMPROF_INTERCEPTOR_ENTER(ctx, strncpy); 245 ENSURE_MEMPROF_INITED(); 246 uptr from_size = Min(size, MaybeRealStrnlen(from, size) + 1); 247 MEMPROF_READ_RANGE(from, from_size); 248 MEMPROF_WRITE_RANGE(to, size); 249 return REAL(strncpy)(to, from, size); 250 } 251 252 INTERCEPTOR(long, strtol, const char *nptr, char **endptr, int base) { 253 void *ctx; 254 MEMPROF_INTERCEPTOR_ENTER(ctx, strtol); 255 ENSURE_MEMPROF_INITED(); 256 char *real_endptr; 257 long result = REAL(strtol)(nptr, &real_endptr, base); 258 StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base); 259 return result; 260 } 261 262 INTERCEPTOR(int, atoi, const char *nptr) { 263 void *ctx; 264 MEMPROF_INTERCEPTOR_ENTER(ctx, atoi); 265 ENSURE_MEMPROF_INITED(); 266 char *real_endptr; 267 // "man atoi" tells that behavior of atoi(nptr) is the same as 268 // strtol(nptr, 0, 10), i.e. it sets errno to ERANGE if the 269 // parsed integer can't be stored in *long* type (even if it's 270 // different from int). So, we just imitate this behavior. 271 int result = REAL(strtol)(nptr, &real_endptr, 10); 272 FixRealStrtolEndptr(nptr, &real_endptr); 273 MEMPROF_READ_STRING(nptr, (real_endptr - nptr) + 1); 274 return result; 275 } 276 277 INTERCEPTOR(long, atol, const char *nptr) { 278 void *ctx; 279 MEMPROF_INTERCEPTOR_ENTER(ctx, atol); 280 ENSURE_MEMPROF_INITED(); 281 char *real_endptr; 282 long result = REAL(strtol)(nptr, &real_endptr, 10); 283 FixRealStrtolEndptr(nptr, &real_endptr); 284 MEMPROF_READ_STRING(nptr, (real_endptr - nptr) + 1); 285 return result; 286 } 287 288 INTERCEPTOR(long long, strtoll, const char *nptr, char **endptr, int base) { 289 void *ctx; 290 MEMPROF_INTERCEPTOR_ENTER(ctx, strtoll); 291 ENSURE_MEMPROF_INITED(); 292 char *real_endptr; 293 long long result = REAL(strtoll)(nptr, &real_endptr, base); 294 StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base); 295 return result; 296 } 297 298 INTERCEPTOR(long long, atoll, const char *nptr) { 299 void *ctx; 300 MEMPROF_INTERCEPTOR_ENTER(ctx, atoll); 301 ENSURE_MEMPROF_INITED(); 302 char *real_endptr; 303 long long result = REAL(strtoll)(nptr, &real_endptr, 10); 304 FixRealStrtolEndptr(nptr, &real_endptr); 305 MEMPROF_READ_STRING(nptr, (real_endptr - nptr) + 1); 306 return result; 307 } 308 309 // ---------------------- InitializeMemprofInterceptors ---------------- {{{1 310 namespace __memprof { 311 void InitializeMemprofInterceptors() { 312 static bool was_called_once; 313 CHECK(!was_called_once); 314 was_called_once = true; 315 InitializeCommonInterceptors(); 316 317 // Intercept str* functions. 318 MEMPROF_INTERCEPT_FUNC(strcat); 319 MEMPROF_INTERCEPT_FUNC(strcpy); 320 MEMPROF_INTERCEPT_FUNC(strncat); 321 MEMPROF_INTERCEPT_FUNC(strncpy); 322 MEMPROF_INTERCEPT_FUNC(strdup); 323 MEMPROF_INTERCEPT_FUNC(__strdup); 324 MEMPROF_INTERCEPT_FUNC(index); 325 326 MEMPROF_INTERCEPT_FUNC(atoi); 327 MEMPROF_INTERCEPT_FUNC(atol); 328 MEMPROF_INTERCEPT_FUNC(strtol); 329 MEMPROF_INTERCEPT_FUNC(atoll); 330 MEMPROF_INTERCEPT_FUNC(strtoll); 331 332 // Intercept threading-related functions 333 MEMPROF_INTERCEPT_FUNC(pthread_create); 334 MEMPROF_INTERCEPT_FUNC(pthread_join); 335 336 InitializePlatformInterceptors(); 337 338 VReport(1, "MemProfiler: libc interceptors initialized\n"); 339 } 340 341 } // namespace __memprof 342