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
MaybeRealStrnlen(const char * s,uptr maxlen)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
SetThreadName(const char * name)36 void SetThreadName(const char *name) {
37 MemprofThread *t = GetCurrentThread();
38 if (t)
39 memprofThreadRegistry().SetThreadName(t->tid(), name);
40 }
41
OnExit()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 MEMPROF_INTERCEPTOR_ENTER(ctx, func) \
56 ctx = 0; \
57 (void)ctx;
58
59 #define COMMON_INTERCEPT_FUNCTION(name) MEMPROF_INTERCEPT_FUNC(name)
60 #define COMMON_INTERCEPT_FUNCTION_VER(name, ver) \
61 MEMPROF_INTERCEPT_FUNC_VER(name, ver)
62 #define COMMON_INTERCEPT_FUNCTION_VER_UNVERSIONED_FALLBACK(name, ver) \
63 MEMPROF_INTERCEPT_FUNC_VER_UNVERSIONED_FALLBACK(name, ver)
64 #define COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ptr, size) \
65 MEMPROF_WRITE_RANGE(ptr, size)
66 #define COMMON_INTERCEPTOR_READ_RANGE(ctx, ptr, size) \
67 MEMPROF_READ_RANGE(ptr, size)
68 #define COMMON_INTERCEPTOR_ENTER(ctx, func, ...) \
69 MEMPROF_INTERCEPTOR_ENTER(ctx, func); \
70 do { \
71 if (memprof_init_is_running) \
72 return REAL(func)(__VA_ARGS__); \
73 ENSURE_MEMPROF_INITED(); \
74 } while (false)
75 #define COMMON_INTERCEPTOR_DIR_ACQUIRE(ctx, path) \
76 do { \
77 } while (false)
78 #define COMMON_INTERCEPTOR_FD_ACQUIRE(ctx, fd) \
79 do { \
80 } while (false)
81 #define COMMON_INTERCEPTOR_FD_RELEASE(ctx, fd) \
82 do { \
83 } while (false)
84 #define COMMON_INTERCEPTOR_FD_SOCKET_ACCEPT(ctx, fd, newfd) \
85 do { \
86 } while (false)
87 #define COMMON_INTERCEPTOR_SET_THREAD_NAME(ctx, name) SetThreadName(name)
88 // Should be memprofThreadRegistry().SetThreadNameByUserId(thread, name)
89 // But memprof does not remember UserId's for threads (pthread_t);
90 // and remembers all ever existed threads, so the linear search by UserId
91 // can be slow.
92 #define COMMON_INTERCEPTOR_SET_PTHREAD_NAME(ctx, thread, name) \
93 do { \
94 } while (false)
95 #define COMMON_INTERCEPTOR_BLOCK_REAL(name) REAL(name)
96 #define COMMON_INTERCEPTOR_ON_EXIT(ctx) OnExit()
97 #define COMMON_INTERCEPTOR_LIBRARY_LOADED(filename, handle)
98 #define COMMON_INTERCEPTOR_LIBRARY_UNLOADED()
99 #define COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED (!memprof_inited)
100 #define COMMON_INTERCEPTOR_GET_TLS_RANGE(begin, end) \
101 if (MemprofThread *t = GetCurrentThread()) { \
102 *begin = t->tls_begin(); \
103 *end = t->tls_end(); \
104 } else { \
105 *begin = *end = 0; \
106 }
107
108 #define COMMON_INTERCEPTOR_MEMMOVE_IMPL(ctx, to, from, size) \
109 do { \
110 MEMPROF_INTERCEPTOR_ENTER(ctx, memmove); \
111 MEMPROF_MEMMOVE_IMPL(to, from, size); \
112 } while (false)
113
114 #define COMMON_INTERCEPTOR_MEMCPY_IMPL(ctx, to, from, size) \
115 do { \
116 MEMPROF_INTERCEPTOR_ENTER(ctx, memcpy); \
117 MEMPROF_MEMCPY_IMPL(to, from, size); \
118 } while (false)
119
120 #define COMMON_INTERCEPTOR_MEMSET_IMPL(ctx, block, c, size) \
121 do { \
122 MEMPROF_INTERCEPTOR_ENTER(ctx, memset); \
123 MEMPROF_MEMSET_IMPL(block, c, size); \
124 } while (false)
125
126 #include "sanitizer_common/sanitizer_common_interceptors.inc"
127
128 #define COMMON_SYSCALL_PRE_READ_RANGE(p, s) MEMPROF_READ_RANGE(p, s)
129 #define COMMON_SYSCALL_PRE_WRITE_RANGE(p, s) MEMPROF_WRITE_RANGE(p, s)
130 #define COMMON_SYSCALL_POST_READ_RANGE(p, s) \
131 do { \
132 (void)(p); \
133 (void)(s); \
134 } while (false)
135 #define COMMON_SYSCALL_POST_WRITE_RANGE(p, s) \
136 do { \
137 (void)(p); \
138 (void)(s); \
139 } while (false)
140 #include "sanitizer_common/sanitizer_common_syscalls.inc"
141
142 struct ThreadStartParam {
143 atomic_uintptr_t t;
144 atomic_uintptr_t is_registered;
145 };
146
memprof_thread_start(void * arg)147 static thread_return_t THREAD_CALLING_CONV memprof_thread_start(void *arg) {
148 ThreadStartParam *param = reinterpret_cast<ThreadStartParam *>(arg);
149 MemprofThread *t = nullptr;
150 while ((t = reinterpret_cast<MemprofThread *>(
151 atomic_load(¶m->t, memory_order_acquire))) == nullptr)
152 internal_sched_yield();
153 SetCurrentThread(t);
154 return t->ThreadStart(GetTid(), ¶m->is_registered);
155 }
156
INTERCEPTOR(int,pthread_create,void * thread,void * attr,void * (* start_routine)(void *),void * arg)157 INTERCEPTOR(int, pthread_create, void *thread, void *attr,
158 void *(*start_routine)(void *), void *arg) {
159 EnsureMainThreadIDIsCorrect();
160 GET_STACK_TRACE_THREAD;
161 int detached = 0;
162 if (attr)
163 REAL(pthread_attr_getdetachstate)(attr, &detached);
164 ThreadStartParam param;
165 atomic_store(¶m.t, 0, memory_order_relaxed);
166 atomic_store(¶m.is_registered, 0, memory_order_relaxed);
167 int result;
168 {
169 // Ignore all allocations made by pthread_create: thread stack/TLS may be
170 // stored by pthread for future reuse even after thread destruction, and
171 // the linked list it's stored in doesn't even hold valid pointers to the
172 // objects, the latter are calculated by obscure pointer arithmetic.
173 result = REAL(pthread_create)(thread, attr, memprof_thread_start, ¶m);
174 }
175 if (result == 0) {
176 u32 current_tid = GetCurrentTidOrInvalid();
177 MemprofThread *t = MemprofThread::Create(start_routine, arg, current_tid,
178 &stack, detached);
179 atomic_store(¶m.t, reinterpret_cast<uptr>(t), memory_order_release);
180 // Wait until the MemprofThread object is initialized and the
181 // ThreadRegistry entry is in "started" state.
182 while (atomic_load(¶m.is_registered, memory_order_acquire) == 0)
183 internal_sched_yield();
184 }
185 return result;
186 }
187
INTERCEPTOR(int,pthread_join,void * t,void ** arg)188 INTERCEPTOR(int, pthread_join, void *t, void **arg) {
189 return real_pthread_join(t, arg);
190 }
191
192 DEFINE_REAL_PTHREAD_FUNCTIONS
193
194 INTERCEPTOR(char *, index, const char *string, int c)
195 ALIAS(WRAPPER_NAME(strchr));
196
197 // For both strcat() and strncat() we need to check the validity of |to|
198 // argument irrespective of the |from| length.
INTERCEPTOR(char *,strcat,char * to,const char * from)199 INTERCEPTOR(char *, strcat, char *to, const char *from) {
200 void *ctx;
201 MEMPROF_INTERCEPTOR_ENTER(ctx, strcat);
202 ENSURE_MEMPROF_INITED();
203 uptr from_length = internal_strlen(from);
204 MEMPROF_READ_RANGE(from, from_length + 1);
205 uptr to_length = internal_strlen(to);
206 MEMPROF_READ_STRING(to, to_length);
207 MEMPROF_WRITE_RANGE(to + to_length, from_length + 1);
208 return REAL(strcat)(to, from);
209 }
210
INTERCEPTOR(char *,strncat,char * to,const char * from,uptr size)211 INTERCEPTOR(char *, strncat, char *to, const char *from, uptr size) {
212 void *ctx;
213 MEMPROF_INTERCEPTOR_ENTER(ctx, strncat);
214 ENSURE_MEMPROF_INITED();
215 uptr from_length = MaybeRealStrnlen(from, size);
216 uptr copy_length = Min(size, from_length + 1);
217 MEMPROF_READ_RANGE(from, copy_length);
218 uptr to_length = internal_strlen(to);
219 MEMPROF_READ_STRING(to, to_length);
220 MEMPROF_WRITE_RANGE(to + to_length, from_length + 1);
221 return REAL(strncat)(to, from, size);
222 }
223
INTERCEPTOR(char *,strcpy,char * to,const char * from)224 INTERCEPTOR(char *, strcpy, char *to, const char *from) {
225 void *ctx;
226 MEMPROF_INTERCEPTOR_ENTER(ctx, strcpy);
227 if (memprof_init_is_running) {
228 return REAL(strcpy)(to, from);
229 }
230 ENSURE_MEMPROF_INITED();
231 uptr from_size = internal_strlen(from) + 1;
232 MEMPROF_READ_RANGE(from, from_size);
233 MEMPROF_WRITE_RANGE(to, from_size);
234 return REAL(strcpy)(to, from);
235 }
236
INTERCEPTOR(char *,strdup,const char * s)237 INTERCEPTOR(char *, strdup, const char *s) {
238 void *ctx;
239 MEMPROF_INTERCEPTOR_ENTER(ctx, strdup);
240 if (UNLIKELY(!memprof_inited))
241 return internal_strdup(s);
242 ENSURE_MEMPROF_INITED();
243 uptr length = internal_strlen(s);
244 MEMPROF_READ_RANGE(s, length + 1);
245 GET_STACK_TRACE_MALLOC;
246 void *new_mem = memprof_malloc(length + 1, &stack);
247 REAL(memcpy)(new_mem, s, length + 1);
248 return reinterpret_cast<char *>(new_mem);
249 }
250
INTERCEPTOR(char *,__strdup,const char * s)251 INTERCEPTOR(char *, __strdup, const char *s) {
252 void *ctx;
253 MEMPROF_INTERCEPTOR_ENTER(ctx, strdup);
254 if (UNLIKELY(!memprof_inited))
255 return internal_strdup(s);
256 ENSURE_MEMPROF_INITED();
257 uptr length = internal_strlen(s);
258 MEMPROF_READ_RANGE(s, length + 1);
259 GET_STACK_TRACE_MALLOC;
260 void *new_mem = memprof_malloc(length + 1, &stack);
261 REAL(memcpy)(new_mem, s, length + 1);
262 return reinterpret_cast<char *>(new_mem);
263 }
264
INTERCEPTOR(char *,strncpy,char * to,const char * from,uptr size)265 INTERCEPTOR(char *, strncpy, char *to, const char *from, uptr size) {
266 void *ctx;
267 MEMPROF_INTERCEPTOR_ENTER(ctx, strncpy);
268 ENSURE_MEMPROF_INITED();
269 uptr from_size = Min(size, MaybeRealStrnlen(from, size) + 1);
270 MEMPROF_READ_RANGE(from, from_size);
271 MEMPROF_WRITE_RANGE(to, size);
272 return REAL(strncpy)(to, from, size);
273 }
274
INTERCEPTOR(long,strtol,const char * nptr,char ** endptr,int base)275 INTERCEPTOR(long, strtol, const char *nptr, char **endptr, int base) {
276 void *ctx;
277 MEMPROF_INTERCEPTOR_ENTER(ctx, strtol);
278 ENSURE_MEMPROF_INITED();
279 char *real_endptr;
280 long result = REAL(strtol)(nptr, &real_endptr, base);
281 StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base);
282 return result;
283 }
284
INTERCEPTOR(int,atoi,const char * nptr)285 INTERCEPTOR(int, atoi, const char *nptr) {
286 void *ctx;
287 MEMPROF_INTERCEPTOR_ENTER(ctx, atoi);
288 ENSURE_MEMPROF_INITED();
289 char *real_endptr;
290 // "man atoi" tells that behavior of atoi(nptr) is the same as
291 // strtol(nptr, 0, 10), i.e. it sets errno to ERANGE if the
292 // parsed integer can't be stored in *long* type (even if it's
293 // different from int). So, we just imitate this behavior.
294 int result = REAL(strtol)(nptr, &real_endptr, 10);
295 FixRealStrtolEndptr(nptr, &real_endptr);
296 MEMPROF_READ_STRING(nptr, (real_endptr - nptr) + 1);
297 return result;
298 }
299
INTERCEPTOR(long,atol,const char * nptr)300 INTERCEPTOR(long, atol, const char *nptr) {
301 void *ctx;
302 MEMPROF_INTERCEPTOR_ENTER(ctx, atol);
303 ENSURE_MEMPROF_INITED();
304 char *real_endptr;
305 long result = REAL(strtol)(nptr, &real_endptr, 10);
306 FixRealStrtolEndptr(nptr, &real_endptr);
307 MEMPROF_READ_STRING(nptr, (real_endptr - nptr) + 1);
308 return result;
309 }
310
INTERCEPTOR(long long,strtoll,const char * nptr,char ** endptr,int base)311 INTERCEPTOR(long long, strtoll, const char *nptr, char **endptr, int base) {
312 void *ctx;
313 MEMPROF_INTERCEPTOR_ENTER(ctx, strtoll);
314 ENSURE_MEMPROF_INITED();
315 char *real_endptr;
316 long long result = REAL(strtoll)(nptr, &real_endptr, base);
317 StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base);
318 return result;
319 }
320
INTERCEPTOR(long long,atoll,const char * nptr)321 INTERCEPTOR(long long, atoll, const char *nptr) {
322 void *ctx;
323 MEMPROF_INTERCEPTOR_ENTER(ctx, atoll);
324 ENSURE_MEMPROF_INITED();
325 char *real_endptr;
326 long long result = REAL(strtoll)(nptr, &real_endptr, 10);
327 FixRealStrtolEndptr(nptr, &real_endptr);
328 MEMPROF_READ_STRING(nptr, (real_endptr - nptr) + 1);
329 return result;
330 }
331
332 // ---------------------- InitializeMemprofInterceptors ---------------- {{{1
333 namespace __memprof {
InitializeMemprofInterceptors()334 void InitializeMemprofInterceptors() {
335 static bool was_called_once;
336 CHECK(!was_called_once);
337 was_called_once = true;
338 InitializeCommonInterceptors();
339
340 // Intercept str* functions.
341 MEMPROF_INTERCEPT_FUNC(strcat);
342 MEMPROF_INTERCEPT_FUNC(strcpy);
343 MEMPROF_INTERCEPT_FUNC(strncat);
344 MEMPROF_INTERCEPT_FUNC(strncpy);
345 MEMPROF_INTERCEPT_FUNC(strdup);
346 MEMPROF_INTERCEPT_FUNC(__strdup);
347 MEMPROF_INTERCEPT_FUNC(index);
348
349 MEMPROF_INTERCEPT_FUNC(atoi);
350 MEMPROF_INTERCEPT_FUNC(atol);
351 MEMPROF_INTERCEPT_FUNC(strtol);
352 MEMPROF_INTERCEPT_FUNC(atoll);
353 MEMPROF_INTERCEPT_FUNC(strtoll);
354
355 // Intercept threading-related functions
356 MEMPROF_INTERCEPT_FUNC(pthread_create);
357 MEMPROF_INTERCEPT_FUNC(pthread_join);
358
359 InitializePlatformInterceptors();
360
361 VReport(1, "MemProfiler: libc interceptors initialized\n");
362 }
363
364 } // namespace __memprof
365