1//===-- tsan_platform_mac.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 ThreadSanitizer (TSan), a race detector.
10//
11// Mac-specific code.
12//===----------------------------------------------------------------------===//
13
14#include "sanitizer_common/sanitizer_platform.h"
15#if SANITIZER_APPLE
16
17#include "sanitizer_common/sanitizer_atomic.h"
18#include "sanitizer_common/sanitizer_common.h"
19#include "sanitizer_common/sanitizer_libc.h"
20#include "sanitizer_common/sanitizer_posix.h"
21#include "sanitizer_common/sanitizer_procmaps.h"
22#include "sanitizer_common/sanitizer_ptrauth.h"
23#include "sanitizer_common/sanitizer_stackdepot.h"
24#include "tsan_platform.h"
25#include "tsan_rtl.h"
26#include "tsan_flags.h"
27
28#include <limits.h>
29#include <mach/mach.h>
30#include <pthread.h>
31#include <signal.h>
32#include <stdio.h>
33#include <stdlib.h>
34#include <string.h>
35#include <stdarg.h>
36#include <sys/mman.h>
37#include <sys/syscall.h>
38#include <sys/time.h>
39#include <sys/types.h>
40#include <sys/resource.h>
41#include <sys/stat.h>
42#include <unistd.h>
43#include <errno.h>
44#include <sched.h>
45
46namespace __tsan {
47
48#if !SANITIZER_GO
49alignas(SANITIZER_CACHE_LINE_SIZE) static char main_thread_state[sizeof(
50 ThreadState)];
51static ThreadState *dead_thread_state;
52static pthread_key_t thread_state_key;
53
54// We rely on the following documented, but Darwin-specific behavior to keep the
55// reference to the ThreadState object alive in TLS:
56// pthread_key_create man page:
57// If, after all the destructors have been called for all non-NULL values with
58// associated destructors, there are still some non-NULL values with
59// associated destructors, then the process is repeated. If, after at least
60// [PTHREAD_DESTRUCTOR_ITERATIONS] iterations of destructor calls for
61// outstanding non-NULL values, there are still some non-NULL values with
62// associated destructors, the implementation stops calling destructors.
63static_assert(PTHREAD_DESTRUCTOR_ITERATIONS == 4, "Small number of iterations");
64static void ThreadStateDestructor(void *thr) {
65 int res = pthread_setspecific(thread_state_key, thr);
66 CHECK_EQ(res, 0);
67}
68
69static void InitializeThreadStateStorage() {
70 int res;
71 CHECK_EQ(thread_state_key, 0);
72 res = pthread_key_create(&thread_state_key, ThreadStateDestructor);
73 CHECK_EQ(res, 0);
74 res = pthread_setspecific(thread_state_key, main_thread_state);
75 CHECK_EQ(res, 0);
76
77 auto dts = (ThreadState *)MmapOrDie(sizeof(ThreadState), "ThreadState");
78 dts->fast_state.SetIgnoreBit();
79 dts->ignore_interceptors = 1;
80 dts->is_dead = true;
81 const_cast<Tid &>(dts->tid) = kInvalidTid;
82 res = internal_mprotect(dts, sizeof(ThreadState), PROT_READ); // immutable
83 CHECK_EQ(res, 0);
84 dead_thread_state = dts;
85}
86
87ThreadState *cur_thread() {
88 // Some interceptors get called before libpthread has been initialized and in
89 // these cases we must avoid calling any pthread APIs.
90 if (UNLIKELY(!thread_state_key)) {
91 return (ThreadState *)main_thread_state;
92 }
93
94 // We only reach this line after InitializeThreadStateStorage() ran, i.e,
95 // after TSan (and therefore libpthread) have been initialized.
96 ThreadState *thr = (ThreadState *)pthread_getspecific(thread_state_key);
97 if (UNLIKELY(!thr)) {
98 thr = (ThreadState *)MmapOrDie(sizeof(ThreadState), "ThreadState");
99 int res = pthread_setspecific(thread_state_key, thr);
100 CHECK_EQ(res, 0);
101 }
102 return thr;
103}
104
105void set_cur_thread(ThreadState *thr) {
106 int res = pthread_setspecific(thread_state_key, thr);
107 CHECK_EQ(res, 0);
108}
109
110void cur_thread_finalize() {
111 ThreadState *thr = (ThreadState *)pthread_getspecific(thread_state_key);
112 CHECK(thr);
113 if (thr == (ThreadState *)main_thread_state) {
114 // Calling dispatch_main() or xpc_main() actually invokes pthread_exit to
115 // exit the main thread. Let's keep the main thread's ThreadState.
116 return;
117 }
118 // Intercepted functions can still get called after cur_thread_finalize()
119 // (called from DestroyThreadState()), so put a fake thread state for "dead"
120 // threads. An alternative solution would be to release the ThreadState
121 // object from THREAD_DESTROY (which is delivered later and on the parent
122 // thread) instead of THREAD_TERMINATE.
123 int res = pthread_setspecific(thread_state_key, dead_thread_state);
124 CHECK_EQ(res, 0);
125 UnmapOrDie(thr, sizeof(ThreadState));
126}
127#endif
128
129static void RegionMemUsage(uptr start, uptr end, uptr *res, uptr *dirty) {
130 vm_address_t address = start;
131 vm_address_t end_address = end;
132 uptr resident_pages = 0;
133 uptr dirty_pages = 0;
134 while (address < end_address) {
135 vm_size_t vm_region_size;
136 mach_msg_type_number_t count = VM_REGION_EXTENDED_INFO_COUNT;
137 vm_region_extended_info_data_t vm_region_info;
138 mach_port_t object_name;
139 kern_return_t ret = vm_region_64(
140 mach_task_self(), &address, &vm_region_size, VM_REGION_EXTENDED_INFO,
141 (vm_region_info_t)&vm_region_info, &count, &object_name);
142 if (ret != KERN_SUCCESS) break;
143
144 resident_pages += vm_region_info.pages_resident;
145 dirty_pages += vm_region_info.pages_dirtied;
146
147 address += vm_region_size;
148 }
149 *res = resident_pages * GetPageSizeCached();
150 *dirty = dirty_pages * GetPageSizeCached();
151}
152
153void WriteMemoryProfile(char *buf, uptr buf_size, u64 uptime_ns) {
154 uptr shadow_res, shadow_dirty;
155 uptr meta_res, meta_dirty;
156 RegionMemUsage(ShadowBeg(), ShadowEnd(), &shadow_res, &shadow_dirty);
157 RegionMemUsage(MetaShadowBeg(), MetaShadowEnd(), &meta_res, &meta_dirty);
158
159# if !SANITIZER_GO
160 uptr low_res, low_dirty;
161 uptr high_res, high_dirty;
162 uptr heap_res, heap_dirty;
163 RegionMemUsage(LoAppMemBeg(), LoAppMemEnd(), &low_res, &low_dirty);
164 RegionMemUsage(HiAppMemBeg(), HiAppMemEnd(), &high_res, &high_dirty);
165 RegionMemUsage(HeapMemBeg(), HeapMemEnd(), &heap_res, &heap_dirty);
166#else // !SANITIZER_GO
167 uptr app_res, app_dirty;
168 RegionMemUsage(LoAppMemBeg(), LoAppMemEnd(), &app_res, &app_dirty);
169#endif
170
171 StackDepotStats stacks = StackDepotGetStats();
172 uptr nthread, nlive;
173 ctx->thread_registry.GetNumberOfThreads(&nthread, &nlive);
174 internal_snprintf(
175 buf, buf_size,
176 "shadow (0x%016zx-0x%016zx): resident %zd kB, dirty %zd kB\n"
177 "meta (0x%016zx-0x%016zx): resident %zd kB, dirty %zd kB\n"
178# if !SANITIZER_GO
179 "low app (0x%016zx-0x%016zx): resident %zd kB, dirty %zd kB\n"
180 "high app (0x%016zx-0x%016zx): resident %zd kB, dirty %zd kB\n"
181 "heap (0x%016zx-0x%016zx): resident %zd kB, dirty %zd kB\n"
182# else // !SANITIZER_GO
183 "app (0x%016zx-0x%016zx): resident %zd kB, dirty %zd kB\n"
184# endif
185 "stacks: %zd unique IDs, %zd kB allocated\n"
186 "threads: %zd total, %zd live\n"
187 "------------------------------\n",
188 ShadowBeg(), ShadowEnd(), shadow_res / 1024, shadow_dirty / 1024,
189 MetaShadowBeg(), MetaShadowEnd(), meta_res / 1024, meta_dirty / 1024,
190# if !SANITIZER_GO
191 LoAppMemBeg(), LoAppMemEnd(), low_res / 1024, low_dirty / 1024,
192 HiAppMemBeg(), HiAppMemEnd(), high_res / 1024, high_dirty / 1024,
193 HeapMemBeg(), HeapMemEnd(), heap_res / 1024, heap_dirty / 1024,
194# else // !SANITIZER_GO
195 LoAppMemBeg(), LoAppMemEnd(), app_res / 1024, app_dirty / 1024,
196# endif
197 stacks.n_uniq_ids, stacks.allocated / 1024, nthread, nlive);
198}
199
200# if !SANITIZER_GO
201void InitializeShadowMemoryPlatform() { }
202
203// Register GCD worker threads, which are created without an observable call to
204// pthread_create().
205static void ThreadCreateCallback(uptr thread, bool gcd_worker) {
206 if (gcd_worker) {
207 ThreadState *thr = cur_thread();
208 Processor *proc = ProcCreate();
209 ProcWire(proc, thr);
210 ThreadState *parent_thread_state = nullptr; // No parent.
211 Tid tid = ThreadCreate(parent_thread_state, 0, (uptr)thread, true);
212 CHECK_NE(tid, kMainTid);
213 ThreadStart(thr, tid, GetTid(), ThreadType::Worker);
214 }
215}
216
217// Destroy thread state for *all* threads.
218static void ThreadTerminateCallback(uptr thread) {
219 ThreadState *thr = cur_thread();
220 if (thr->tctx) {
221 DestroyThreadState();
222 }
223}
224#endif
225
226void InitializePlatformEarly() {
227# if !SANITIZER_GO && SANITIZER_IOS
228 uptr max_vm = GetMaxUserVirtualAddress() + 1;
229 if (max_vm != HiAppMemEnd()) {
230 Printf("ThreadSanitizer: unsupported vm address limit %p, expected %p.\n",
231 (void *)max_vm, (void *)HiAppMemEnd());
232 Die();
233 }
234#endif
235}
236
237static uptr longjmp_xor_key = 0;
238
239void InitializePlatform() {
240 DisableCoreDumperIfNecessary();
241#if !SANITIZER_GO
242 if (!CheckAndProtect(true, true, true)) {
243 Printf("FATAL: ThreadSanitizer: found incompatible memory layout.\n");
244 Die();
245 }
246
247 InitializeThreadStateStorage();
248
249 ThreadEventCallbacks callbacks = {
250 .create = ThreadCreateCallback,
251 .terminate = ThreadTerminateCallback,
252 };
253 InstallPthreadIntrospectionHook(callbacks);
254#endif
255
256 if (GetMacosAlignedVersion() >= MacosVersion(10, 14)) {
257 // Libsystem currently uses a process-global key; this might change.
258 const unsigned kTLSLongjmpXorKeySlot = 0x7;
259 longjmp_xor_key = (uptr)pthread_getspecific(kTLSLongjmpXorKeySlot);
260 }
261}
262
263#ifdef __aarch64__
264# define LONG_JMP_SP_ENV_SLOT \
265 ((GetMacosAlignedVersion() >= MacosVersion(10, 14)) ? 12 : 13)
266#else
267# define LONG_JMP_SP_ENV_SLOT 2
268#endif
269
270uptr ExtractLongJmpSp(uptr *env) {
271 uptr mangled_sp = env[LONG_JMP_SP_ENV_SLOT];
272 uptr sp = mangled_sp ^ longjmp_xor_key;
273 sp = (uptr)ptrauth_auth_data((void *)sp, ptrauth_key_asdb,
274 ptrauth_string_discriminator("sp"));
275 return sp;
276}
277
278#if !SANITIZER_GO
279extern "C" void __tsan_tls_initialization() {}
280
281void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size) {
282 const uptr pc = StackTrace::GetNextInstructionPc(
283 reinterpret_cast<uptr>(__tsan_tls_initialization));
284 // Unlike Linux, we only store a pointer to the ThreadState object in TLS;
285 // just mark the entire range as written to.
286 MemoryRangeImitateWrite(thr, pc, tls_addr, tls_size);
287}
288#endif
289
290#if !SANITIZER_GO
291// Note: this function runs with async signals enabled,
292// so it must not touch any tsan state.
293int call_pthread_cancel_with_cleanup(int (*fn)(void *arg),
294 void (*cleanup)(void *arg), void *arg) {
295 // pthread_cleanup_push/pop are hardcore macros mess.
296 // We can't intercept nor call them w/o including pthread.h.
297 int res;
298 pthread_cleanup_push(cleanup, arg);
299 res = fn(arg);
300 pthread_cleanup_pop(0);
301 return res;
302}
303#endif
304
305} // namespace __tsan
306
307#endif // SANITIZER_APPLE
308

source code of compiler-rt/lib/tsan/rtl/tsan_platform_mac.cpp