1//===-- tsan_platform_linux.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// Linux- and BSD-specific code.
12//===----------------------------------------------------------------------===//
13
14#include "sanitizer_common/sanitizer_platform.h"
15#if SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD
16
17#include "sanitizer_common/sanitizer_common.h"
18#include "sanitizer_common/sanitizer_libc.h"
19#include "sanitizer_common/sanitizer_linux.h"
20#include "sanitizer_common/sanitizer_platform_limits_netbsd.h"
21#include "sanitizer_common/sanitizer_platform_limits_posix.h"
22#include "sanitizer_common/sanitizer_posix.h"
23#include "sanitizer_common/sanitizer_procmaps.h"
24#include "sanitizer_common/sanitizer_stackdepot.h"
25#include "sanitizer_common/sanitizer_stoptheworld.h"
26#include "tsan_flags.h"
27#include "tsan_platform.h"
28#include "tsan_rtl.h"
29
30#include <fcntl.h>
31#include <pthread.h>
32#include <signal.h>
33#include <stdio.h>
34#include <stdlib.h>
35#include <string.h>
36#include <stdarg.h>
37#include <sys/mman.h>
38#if SANITIZER_LINUX
39#include <sys/personality.h>
40#include <setjmp.h>
41#endif
42#include <sys/syscall.h>
43#include <sys/socket.h>
44#include <sys/time.h>
45#include <sys/types.h>
46#include <sys/resource.h>
47#include <sys/stat.h>
48#include <unistd.h>
49#include <sched.h>
50#include <dlfcn.h>
51#if SANITIZER_LINUX
52#define __need_res_state
53#include <resolv.h>
54#endif
55
56#ifdef sa_handler
57# undef sa_handler
58#endif
59
60#ifdef sa_sigaction
61# undef sa_sigaction
62#endif
63
64#if SANITIZER_FREEBSD
65extern "C" void *__libc_stack_end;
66void *__libc_stack_end = 0;
67#endif
68
69#if SANITIZER_LINUX && (defined(__aarch64__) || defined(__loongarch_lp64)) && \
70 !SANITIZER_GO
71# define INIT_LONGJMP_XOR_KEY 1
72#else
73# define INIT_LONGJMP_XOR_KEY 0
74#endif
75
76#if INIT_LONGJMP_XOR_KEY
77#include "interception/interception.h"
78// Must be declared outside of other namespaces.
79DECLARE_REAL(int, _setjmp, void *env)
80#endif
81
82namespace __tsan {
83
84#if INIT_LONGJMP_XOR_KEY
85static void InitializeLongjmpXorKey();
86static uptr longjmp_xor_key;
87#endif
88
89// Runtime detected VMA size.
90uptr vmaSize;
91
92enum {
93 MemTotal,
94 MemShadow,
95 MemMeta,
96 MemFile,
97 MemMmap,
98 MemHeap,
99 MemOther,
100 MemCount,
101};
102
103void FillProfileCallback(uptr p, uptr rss, bool file, uptr *mem) {
104 mem[MemTotal] += rss;
105 if (p >= ShadowBeg() && p < ShadowEnd())
106 mem[MemShadow] += rss;
107 else if (p >= MetaShadowBeg() && p < MetaShadowEnd())
108 mem[MemMeta] += rss;
109 else if ((p >= LoAppMemBeg() && p < LoAppMemEnd()) ||
110 (p >= MidAppMemBeg() && p < MidAppMemEnd()) ||
111 (p >= HiAppMemBeg() && p < HiAppMemEnd()))
112 mem[file ? MemFile : MemMmap] += rss;
113 else if (p >= HeapMemBeg() && p < HeapMemEnd())
114 mem[MemHeap] += rss;
115 else
116 mem[MemOther] += rss;
117}
118
119void WriteMemoryProfile(char *buf, uptr buf_size, u64 uptime_ns) {
120 uptr mem[MemCount];
121 internal_memset(s: mem, c: 0, n: sizeof(mem));
122 GetMemoryProfile(cb: FillProfileCallback, stats: mem);
123 auto meta = ctx->metamap.GetMemoryStats();
124 StackDepotStats stacks = StackDepotGetStats();
125 uptr nthread, nlive;
126 ctx->thread_registry.GetNumberOfThreads(total: &nthread, running: &nlive);
127 uptr trace_mem;
128 {
129 Lock l(&ctx->slot_mtx);
130 trace_mem = ctx->trace_part_total_allocated * sizeof(TracePart);
131 }
132 uptr internal_stats[AllocatorStatCount];
133 internal_allocator()->GetStats(s: internal_stats);
134 // All these are allocated from the common mmap region.
135 mem[MemMmap] -= meta.mem_block + meta.sync_obj + trace_mem +
136 stacks.allocated + internal_stats[AllocatorStatMapped];
137 if (s64(mem[MemMmap]) < 0)
138 mem[MemMmap] = 0;
139 internal_snprintf(
140 buffer: buf, length: buf_size,
141 format: "==%zu== %llus [%zu]: RSS %zd MB: shadow:%zd meta:%zd file:%zd"
142 " mmap:%zd heap:%zd other:%zd intalloc:%zd memblocks:%zd syncobj:%zu"
143 " trace:%zu stacks=%zd threads=%zu/%zu\n",
144 internal_getpid(), uptime_ns / (1000 * 1000 * 1000), ctx->global_epoch,
145 mem[MemTotal] >> 20, mem[MemShadow] >> 20, mem[MemMeta] >> 20,
146 mem[MemFile] >> 20, mem[MemMmap] >> 20, mem[MemHeap] >> 20,
147 mem[MemOther] >> 20, internal_stats[AllocatorStatMapped] >> 20,
148 meta.mem_block >> 20, meta.sync_obj >> 20, trace_mem >> 20,
149 stacks.allocated >> 20, nlive, nthread);
150}
151
152#if !SANITIZER_GO
153// Mark shadow for .rodata sections with the special Shadow::kRodata marker.
154// Accesses to .rodata can't race, so this saves time, memory and trace space.
155static NOINLINE void MapRodata(char* buffer, uptr size) {
156 // First create temp file.
157 const char *tmpdir = GetEnv(name: "TMPDIR");
158 if (tmpdir == 0)
159 tmpdir = GetEnv(name: "TEST_TMPDIR");
160#ifdef P_tmpdir
161 if (tmpdir == 0)
162 tmpdir = P_tmpdir;
163#endif
164 if (tmpdir == 0)
165 return;
166 internal_snprintf(buffer, length: size, format: "%s/tsan.rodata.%d",
167 tmpdir, (int)internal_getpid());
168 uptr openrv = internal_open(filename: buffer, O_RDWR | O_CREAT | O_EXCL, mode: 0600);
169 if (internal_iserror(retval: openrv))
170 return;
171 internal_unlink(path: buffer); // Unlink it now, so that we can reuse the buffer.
172 fd_t fd = openrv;
173 // Fill the file with Shadow::kRodata.
174 const uptr kMarkerSize = 512 * 1024 / sizeof(RawShadow);
175 InternalMmapVector<RawShadow> marker(kMarkerSize);
176 // volatile to prevent insertion of memset
177 for (volatile RawShadow *p = marker.data(); p < marker.data() + kMarkerSize;
178 p++)
179 *p = Shadow::kRodata;
180 internal_write(fd, buf: marker.data(), count: marker.size() * sizeof(RawShadow));
181 // Map the file into memory.
182 uptr page = internal_mmap(addr: 0, length: GetPageSizeCached(), PROT_READ | PROT_WRITE,
183 MAP_PRIVATE | MAP_ANONYMOUS, fd, offset: 0);
184 if (internal_iserror(retval: page)) {
185 internal_close(fd);
186 return;
187 }
188 // Map the file into shadow of .rodata sections.
189 MemoryMappingLayout proc_maps(/*cache_enabled*/true);
190 // Reusing the buffer 'buffer'.
191 MemoryMappedSegment segment(buffer, size);
192 while (proc_maps.Next(segment: &segment)) {
193 if (segment.filename[0] != 0 && segment.filename[0] != '[' &&
194 segment.IsReadable() && segment.IsExecutable() &&
195 !segment.IsWritable() && IsAppMem(mem: segment.start)) {
196 // Assume it's .rodata
197 char *shadow_start = (char *)MemToShadow(x: segment.start);
198 char *shadow_end = (char *)MemToShadow(x: segment.end);
199 for (char *p = shadow_start; p < shadow_end;
200 p += marker.size() * sizeof(RawShadow)) {
201 internal_mmap(
202 addr: p, length: Min<uptr>(a: marker.size() * sizeof(RawShadow), b: shadow_end - p),
203 PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, offset: 0);
204 }
205 }
206 }
207 internal_close(fd);
208}
209
210void InitializeShadowMemoryPlatform() {
211 char buffer[256]; // Keep in a different frame.
212 MapRodata(buffer, size: sizeof(buffer));
213}
214
215#endif // #if !SANITIZER_GO
216
217# if !SANITIZER_GO
218static void ReExecIfNeeded(bool ignore_heap) {
219 // Go maps shadow memory lazily and works fine with limited address space.
220 // Unlimited stack is not a problem as well, because the executable
221 // is not compiled with -pie.
222 bool reexec = false;
223 // TSan doesn't play well with unlimited stack size (as stack
224 // overlaps with shadow memory). If we detect unlimited stack size,
225 // we re-exec the program with limited stack size as a best effort.
226 if (StackSizeIsUnlimited()) {
227 const uptr kMaxStackSize = 32 * 1024 * 1024;
228 VReport(1,
229 "Program is run with unlimited stack size, which wouldn't "
230 "work with ThreadSanitizer.\n"
231 "Re-execing with stack size limited to %zd bytes.\n",
232 kMaxStackSize);
233 SetStackSizeLimitInBytes(kMaxStackSize);
234 reexec = true;
235 }
236
237 if (!AddressSpaceIsUnlimited()) {
238 Report(
239 format: "WARNING: Program is run with limited virtual address space,"
240 " which wouldn't work with ThreadSanitizer.\n");
241 Report(format: "Re-execing with unlimited virtual address space.\n");
242 SetAddressSpaceUnlimited();
243 reexec = true;
244 }
245
246# if SANITIZER_LINUX
247# if SANITIZER_ANDROID && (defined(__aarch64__) || defined(__x86_64__))
248 // ASLR personality check.
249 int old_personality = personality(0xffffffff);
250 bool aslr_on =
251 (old_personality != -1) && ((old_personality & ADDR_NO_RANDOMIZE) == 0);
252
253 // After patch "arm64: mm: support ARCH_MMAP_RND_BITS." is introduced in
254 // linux kernel, the random gap between stack and mapped area is increased
255 // from 128M to 36G on 39-bit aarch64. As it is almost impossible to cover
256 // this big range, we should disable randomized virtual space on aarch64.
257 if (aslr_on) {
258 VReport(1,
259 "WARNING: Program is run with randomized virtual address "
260 "space, which wouldn't work with ThreadSanitizer on Android.\n"
261 "Re-execing with fixed virtual address space.\n");
262 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1);
263 reexec = true;
264 }
265# endif
266
267 if (reexec) {
268 // Don't check the address space since we're going to re-exec anyway.
269 } else if (!CheckAndProtect(protect: false, ignore_heap, print_warnings: false)) {
270 // ASLR personality check.
271 // N.B. 'personality' is sometimes forbidden by sandboxes, so we only call
272 // this as a last resort (when the memory mapping is incompatible and TSan
273 // would fail anyway).
274 int old_personality = personality(persona: 0xffffffff);
275 bool aslr_on =
276 (old_personality != -1) && ((old_personality & ADDR_NO_RANDOMIZE) == 0);
277
278 if (aslr_on) {
279 // Disable ASLR if the memory layout was incompatible.
280 // Alternatively, we could just keep re-execing until we get lucky
281 // with a compatible randomized layout, but the risk is that if it's
282 // not an ASLR-related issue, we will be stuck in an infinite loop of
283 // re-execing (unless we change ReExec to pass a parameter of the
284 // number of retries allowed.)
285 VReport(1,
286 "WARNING: ThreadSanitizer: memory layout is incompatible, "
287 "possibly due to high-entropy ASLR.\n"
288 "Re-execing with fixed virtual address space.\n"
289 "N.B. reducing ASLR entropy is preferable.\n");
290 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1);
291 reexec = true;
292 } else {
293 Printf(
294 format: "FATAL: ThreadSanitizer: memory layout is incompatible, "
295 "even though ASLR is disabled.\n"
296 "Please file a bug.\n");
297 DumpProcessMap();
298 Die();
299 }
300 }
301# endif // SANITIZER_LINUX
302
303 if (reexec)
304 ReExec();
305}
306# endif
307
308void InitializePlatformEarly() {
309 vmaSize =
310 (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1);
311#if defined(__aarch64__)
312# if !SANITIZER_GO
313 if (vmaSize != 39 && vmaSize != 42 && vmaSize != 48) {
314 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
315 Printf("FATAL: Found %zd - Supported 39, 42 and 48\n", vmaSize);
316 Die();
317 }
318#else
319 if (vmaSize != 48) {
320 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
321 Printf("FATAL: Found %zd - Supported 48\n", vmaSize);
322 Die();
323 }
324#endif
325#elif SANITIZER_LOONGARCH64
326# if !SANITIZER_GO
327 if (vmaSize != 47) {
328 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
329 Printf("FATAL: Found %zd - Supported 47\n", vmaSize);
330 Die();
331 }
332# else
333 if (vmaSize != 47) {
334 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
335 Printf("FATAL: Found %zd - Supported 47\n", vmaSize);
336 Die();
337 }
338# endif
339#elif defined(__powerpc64__)
340# if !SANITIZER_GO
341 if (vmaSize != 44 && vmaSize != 46 && vmaSize != 47) {
342 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
343 Printf("FATAL: Found %zd - Supported 44, 46, and 47\n", vmaSize);
344 Die();
345 }
346# else
347 if (vmaSize != 46 && vmaSize != 47) {
348 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
349 Printf("FATAL: Found %zd - Supported 46, and 47\n", vmaSize);
350 Die();
351 }
352# endif
353#elif defined(__mips64)
354# if !SANITIZER_GO
355 if (vmaSize != 40) {
356 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
357 Printf("FATAL: Found %zd - Supported 40\n", vmaSize);
358 Die();
359 }
360# else
361 if (vmaSize != 47) {
362 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
363 Printf("FATAL: Found %zd - Supported 47\n", vmaSize);
364 Die();
365 }
366# endif
367# elif SANITIZER_RISCV64
368 // the bottom half of vma is allocated for userspace
369 vmaSize = vmaSize + 1;
370# if !SANITIZER_GO
371 if (vmaSize != 39 && vmaSize != 48) {
372 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
373 Printf("FATAL: Found %zd - Supported 39 and 48\n", vmaSize);
374 Die();
375 }
376# endif
377# endif
378
379# if !SANITIZER_GO
380 // Heap has not been allocated yet
381 ReExecIfNeeded(ignore_heap: false);
382# endif
383}
384
385void InitializePlatform() {
386 DisableCoreDumperIfNecessary();
387
388 // Go maps shadow memory lazily and works fine with limited address space.
389 // Unlimited stack is not a problem as well, because the executable
390 // is not compiled with -pie.
391#if !SANITIZER_GO
392 {
393# if SANITIZER_LINUX && (defined(__aarch64__) || defined(__loongarch_lp64))
394 // Initialize the xor key used in {sig}{set,long}jump.
395 InitializeLongjmpXorKey();
396# endif
397 }
398
399 // We called ReExecIfNeeded() in InitializePlatformEarly(), but there are
400 // intervening allocations that result in an edge case:
401 // 1) InitializePlatformEarly(): memory layout is compatible
402 // 2) Intervening allocations happen
403 // 3) InitializePlatform(): memory layout is incompatible and fails
404 // CheckAndProtect()
405# if !SANITIZER_GO
406 // Heap has already been allocated
407 ReExecIfNeeded(ignore_heap: true);
408# endif
409
410 // Earlier initialization steps already re-exec'ed until we got a compatible
411 // memory layout, so we don't expect any more issues here.
412 if (!CheckAndProtect(protect: true, ignore_heap: true, print_warnings: true)) {
413 Printf(
414 format: "FATAL: ThreadSanitizer: unexpectedly found incompatible memory "
415 "layout.\n");
416 Printf(format: "FATAL: Please file a bug.\n");
417 DumpProcessMap();
418 Die();
419 }
420
421 InitTlsSize();
422#endif // !SANITIZER_GO
423}
424
425#if !SANITIZER_GO
426// Extract file descriptors passed to glibc internal __res_iclose function.
427// This is required to properly "close" the fds, because we do not see internal
428// closes within glibc. The code is a pure hack.
429int ExtractResolvFDs(void *state, int *fds, int nfd) {
430#if SANITIZER_LINUX && !SANITIZER_ANDROID
431 int cnt = 0;
432 struct __res_state *statp = (struct __res_state*)state;
433 for (int i = 0; i < MAXNS && cnt < nfd; i++) {
434 if (statp->_u._ext.nsaddrs[i] && statp->_u._ext.nssocks[i] != -1)
435 fds[cnt++] = statp->_u._ext.nssocks[i];
436 }
437 return cnt;
438#else
439 return 0;
440#endif
441}
442
443// Extract file descriptors passed via UNIX domain sockets.
444// This is required to properly handle "open" of these fds.
445// see 'man recvmsg' and 'man 3 cmsg'.
446int ExtractRecvmsgFDs(void *msgp, int *fds, int nfd) {
447 int res = 0;
448 msghdr *msg = (msghdr*)msgp;
449 struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg);
450 for (; cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
451 if (cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS)
452 continue;
453 int n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(fds[0]);
454 for (int i = 0; i < n; i++) {
455 fds[res++] = ((int*)CMSG_DATA(cmsg))[i];
456 if (res == nfd)
457 return res;
458 }
459 }
460 return res;
461}
462
463// Reverse operation of libc stack pointer mangling
464static uptr UnmangleLongJmpSp(uptr mangled_sp) {
465#if defined(__x86_64__)
466# if SANITIZER_LINUX
467 // Reverse of:
468 // xor %fs:0x30, %rsi
469 // rol $0x11, %rsi
470 uptr sp;
471 asm("ror $0x11, %0 \n"
472 "xor %%fs:0x30, %0 \n"
473 : "=r" (sp)
474 : "0" (mangled_sp));
475 return sp;
476# else
477 return mangled_sp;
478# endif
479#elif defined(__aarch64__)
480# if SANITIZER_LINUX
481 return mangled_sp ^ longjmp_xor_key;
482# else
483 return mangled_sp;
484# endif
485#elif defined(__loongarch_lp64)
486 return mangled_sp ^ longjmp_xor_key;
487#elif defined(__powerpc64__)
488 // Reverse of:
489 // ld r4, -28696(r13)
490 // xor r4, r3, r4
491 uptr xor_key;
492 asm("ld %0, -28696(%%r13)" : "=r" (xor_key));
493 return mangled_sp ^ xor_key;
494#elif defined(__mips__)
495 return mangled_sp;
496# elif SANITIZER_RISCV64
497 return mangled_sp;
498# elif defined(__s390x__)
499 // tcbhead_t.stack_guard
500 uptr xor_key = ((uptr *)__builtin_thread_pointer())[5];
501 return mangled_sp ^ xor_key;
502# else
503# error "Unknown platform"
504# endif
505}
506
507#if SANITIZER_NETBSD
508# ifdef __x86_64__
509# define LONG_JMP_SP_ENV_SLOT 6
510# else
511# error unsupported
512# endif
513#elif defined(__powerpc__)
514# define LONG_JMP_SP_ENV_SLOT 0
515#elif SANITIZER_FREEBSD
516# ifdef __aarch64__
517# define LONG_JMP_SP_ENV_SLOT 1
518# else
519# define LONG_JMP_SP_ENV_SLOT 2
520# endif
521#elif SANITIZER_LINUX
522# ifdef __aarch64__
523# define LONG_JMP_SP_ENV_SLOT 13
524# elif defined(__loongarch__)
525# define LONG_JMP_SP_ENV_SLOT 1
526# elif defined(__mips64)
527# define LONG_JMP_SP_ENV_SLOT 1
528# elif SANITIZER_RISCV64
529# define LONG_JMP_SP_ENV_SLOT 13
530# elif defined(__s390x__)
531# define LONG_JMP_SP_ENV_SLOT 9
532# else
533# define LONG_JMP_SP_ENV_SLOT 6
534# endif
535#endif
536
537uptr ExtractLongJmpSp(uptr *env) {
538 uptr mangled_sp = env[LONG_JMP_SP_ENV_SLOT];
539 return UnmangleLongJmpSp(mangled_sp);
540}
541
542#if INIT_LONGJMP_XOR_KEY
543// GLIBC mangles the function pointers in jmp_buf (used in {set,long}*jmp
544// functions) by XORing them with a random key. For AArch64 it is a global
545// variable rather than a TCB one (as for x86_64/powerpc). We obtain the key by
546// issuing a setjmp and XORing the SP pointer values to derive the key.
547static void InitializeLongjmpXorKey() {
548 // 1. Call REAL(setjmp), which stores the mangled SP in env.
549 jmp_buf env;
550 REAL(_setjmp)(env);
551
552 // 2. Retrieve vanilla/mangled SP.
553 uptr sp;
554#ifdef __loongarch__
555 asm("move %0, $sp" : "=r" (sp));
556#else
557 asm("mov %0, sp" : "=r" (sp));
558#endif
559 uptr mangled_sp = ((uptr *)&env)[LONG_JMP_SP_ENV_SLOT];
560
561 // 3. xor SPs to obtain key.
562 longjmp_xor_key = mangled_sp ^ sp;
563}
564#endif
565
566extern "C" void __tsan_tls_initialization() {}
567
568void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size) {
569 // Check that the thr object is in tls;
570 const uptr thr_beg = (uptr)thr;
571 const uptr thr_end = (uptr)thr + sizeof(*thr);
572 CHECK_GE(thr_beg, tls_addr);
573 CHECK_LE(thr_beg, tls_addr + tls_size);
574 CHECK_GE(thr_end, tls_addr);
575 CHECK_LE(thr_end, tls_addr + tls_size);
576 // Since the thr object is huge, skip it.
577 const uptr pc = StackTrace::GetNextInstructionPc(
578 pc: reinterpret_cast<uptr>(__tsan_tls_initialization));
579 MemoryRangeImitateWrite(thr, pc, addr: tls_addr, size: thr_beg - tls_addr);
580 MemoryRangeImitateWrite(thr, pc, addr: thr_end, size: tls_addr + tls_size - thr_end);
581}
582
583// Note: this function runs with async signals enabled,
584// so it must not touch any tsan state.
585int call_pthread_cancel_with_cleanup(int (*fn)(void *arg),
586 void (*cleanup)(void *arg), void *arg) {
587 // pthread_cleanup_push/pop are hardcore macros mess.
588 // We can't intercept nor call them w/o including pthread.h.
589 int res;
590 pthread_cleanup_push(cleanup, arg);
591 res = fn(arg);
592 pthread_cleanup_pop(0);
593 return res;
594}
595#endif // !SANITIZER_GO
596
597#if !SANITIZER_GO
598void ReplaceSystemMalloc() { }
599#endif
600
601#if !SANITIZER_GO
602#if SANITIZER_ANDROID
603// On Android, one thread can call intercepted functions after
604// DestroyThreadState(), so add a fake thread state for "dead" threads.
605static ThreadState *dead_thread_state = nullptr;
606
607ThreadState *cur_thread() {
608 ThreadState* thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
609 if (thr == nullptr) {
610 __sanitizer_sigset_t emptyset;
611 internal_sigfillset(&emptyset);
612 __sanitizer_sigset_t oldset;
613 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &emptyset, &oldset));
614 thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
615 if (thr == nullptr) {
616 thr = reinterpret_cast<ThreadState*>(MmapOrDie(sizeof(ThreadState),
617 "ThreadState"));
618 *get_android_tls_ptr() = reinterpret_cast<uptr>(thr);
619 if (dead_thread_state == nullptr) {
620 dead_thread_state = reinterpret_cast<ThreadState*>(
621 MmapOrDie(sizeof(ThreadState), "ThreadState"));
622 dead_thread_state->fast_state.SetIgnoreBit();
623 dead_thread_state->ignore_interceptors = 1;
624 dead_thread_state->is_dead = true;
625 *const_cast<u32*>(&dead_thread_state->tid) = -1;
626 CHECK_EQ(0, internal_mprotect(dead_thread_state, sizeof(ThreadState),
627 PROT_READ));
628 }
629 }
630 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &oldset, nullptr));
631 }
632 return thr;
633}
634
635void set_cur_thread(ThreadState *thr) {
636 *get_android_tls_ptr() = reinterpret_cast<uptr>(thr);
637}
638
639void cur_thread_finalize() {
640 __sanitizer_sigset_t emptyset;
641 internal_sigfillset(&emptyset);
642 __sanitizer_sigset_t oldset;
643 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &emptyset, &oldset));
644 ThreadState* thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
645 if (thr != dead_thread_state) {
646 *get_android_tls_ptr() = reinterpret_cast<uptr>(dead_thread_state);
647 UnmapOrDie(thr, sizeof(ThreadState));
648 }
649 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &oldset, nullptr));
650}
651#endif // SANITIZER_ANDROID
652#endif // if !SANITIZER_GO
653
654} // namespace __tsan
655
656#endif // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD
657