--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libsanitizer/tsan/tsan_platform_linux.cpp	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,515 @@
+//===-- tsan_platform_linux.cpp -------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of ThreadSanitizer (TSan), a race detector.
+//
+// Linux- and FreeBSD-specific code.
+//===----------------------------------------------------------------------===//
+
+
+#include "sanitizer_common/sanitizer_platform.h"
+#if SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD
+
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_libc.h"
+#include "sanitizer_common/sanitizer_linux.h"
+#include "sanitizer_common/sanitizer_platform_limits_netbsd.h"
+#include "sanitizer_common/sanitizer_platform_limits_posix.h"
+#include "sanitizer_common/sanitizer_posix.h"
+#include "sanitizer_common/sanitizer_procmaps.h"
+#include "sanitizer_common/sanitizer_stoptheworld.h"
+#include "sanitizer_common/sanitizer_stackdepot.h"
+#include "tsan_platform.h"
+#include "tsan_rtl.h"
+#include "tsan_flags.h"
+
+#include <fcntl.h>
+#include <pthread.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <sys/mman.h>
+#if SANITIZER_LINUX
+#include <sys/personality.h>
+#include <setjmp.h>
+#endif
+#include <sys/syscall.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/resource.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <sched.h>
+#include <dlfcn.h>
+#if SANITIZER_LINUX
+#define __need_res_state
+#include <resolv.h>
+#endif
+
+#ifdef sa_handler
+# undef sa_handler
+#endif
+
+#ifdef sa_sigaction
+# undef sa_sigaction
+#endif
+
+#if SANITIZER_FREEBSD
+extern "C" void *__libc_stack_end;
+void *__libc_stack_end = 0;
+#endif
+
+#if SANITIZER_LINUX && defined(__aarch64__) && !SANITIZER_GO
+# define INIT_LONGJMP_XOR_KEY 1
+#else
+# define INIT_LONGJMP_XOR_KEY 0
+#endif
+
+#if INIT_LONGJMP_XOR_KEY
+#include "interception/interception.h"
+// Must be declared outside of other namespaces.
+DECLARE_REAL(int, _setjmp, void *env)
+#endif
+
+namespace __tsan {
+
+#if INIT_LONGJMP_XOR_KEY
+static void InitializeLongjmpXorKey();
+static uptr longjmp_xor_key;
+#endif
+
+#ifdef TSAN_RUNTIME_VMA
+// Runtime detected VMA size.
+uptr vmaSize;
+#endif
+
+enum {
+  MemTotal  = 0,
+  MemShadow = 1,
+  MemMeta   = 2,
+  MemFile   = 3,
+  MemMmap   = 4,
+  MemTrace  = 5,
+  MemHeap   = 6,
+  MemOther  = 7,
+  MemCount  = 8,
+};
+
+void FillProfileCallback(uptr p, uptr rss, bool file,
+                         uptr *mem, uptr stats_size) {
+  mem[MemTotal] += rss;
+  if (p >= ShadowBeg() && p < ShadowEnd())
+    mem[MemShadow] += rss;
+  else if (p >= MetaShadowBeg() && p < MetaShadowEnd())
+    mem[MemMeta] += rss;
+#if !SANITIZER_GO
+  else if (p >= HeapMemBeg() && p < HeapMemEnd())
+    mem[MemHeap] += rss;
+  else if (p >= LoAppMemBeg() && p < LoAppMemEnd())
+    mem[file ? MemFile : MemMmap] += rss;
+  else if (p >= HiAppMemBeg() && p < HiAppMemEnd())
+    mem[file ? MemFile : MemMmap] += rss;
+#else
+  else if (p >= AppMemBeg() && p < AppMemEnd())
+    mem[file ? MemFile : MemMmap] += rss;
+#endif
+  else if (p >= TraceMemBeg() && p < TraceMemEnd())
+    mem[MemTrace] += rss;
+  else
+    mem[MemOther] += rss;
+}
+
+void WriteMemoryProfile(char *buf, uptr buf_size, uptr nthread, uptr nlive) {
+  uptr mem[MemCount];
+  internal_memset(mem, 0, sizeof(mem[0]) * MemCount);
+  __sanitizer::GetMemoryProfile(FillProfileCallback, mem, 7);
+  StackDepotStats *stacks = StackDepotGetStats();
+  internal_snprintf(buf, buf_size,
+      "RSS %zd MB: shadow:%zd meta:%zd file:%zd mmap:%zd"
+      " trace:%zd heap:%zd other:%zd stacks=%zd[%zd] nthr=%zd/%zd\n",
+      mem[MemTotal] >> 20, mem[MemShadow] >> 20, mem[MemMeta] >> 20,
+      mem[MemFile] >> 20, mem[MemMmap] >> 20, mem[MemTrace] >> 20,
+      mem[MemHeap] >> 20, mem[MemOther] >> 20,
+      stacks->allocated >> 20, stacks->n_uniq_ids,
+      nlive, nthread);
+}
+
+#if SANITIZER_LINUX
+void FlushShadowMemoryCallback(
+    const SuspendedThreadsList &suspended_threads_list,
+    void *argument) {
+  ReleaseMemoryPagesToOS(ShadowBeg(), ShadowEnd());
+}
+#endif
+
+void FlushShadowMemory() {
+#if SANITIZER_LINUX
+  StopTheWorld(FlushShadowMemoryCallback, 0);
+#endif
+}
+
+#if !SANITIZER_GO
+// Mark shadow for .rodata sections with the special kShadowRodata marker.
+// Accesses to .rodata can't race, so this saves time, memory and trace space.
+static void MapRodata() {
+  // First create temp file.
+  const char *tmpdir = GetEnv("TMPDIR");
+  if (tmpdir == 0)
+    tmpdir = GetEnv("TEST_TMPDIR");
+#ifdef P_tmpdir
+  if (tmpdir == 0)
+    tmpdir = P_tmpdir;
+#endif
+  if (tmpdir == 0)
+    return;
+  char name[256];
+  internal_snprintf(name, sizeof(name), "%s/tsan.rodata.%d",
+                    tmpdir, (int)internal_getpid());
+  uptr openrv = internal_open(name, O_RDWR | O_CREAT | O_EXCL, 0600);
+  if (internal_iserror(openrv))
+    return;
+  internal_unlink(name);  // Unlink it now, so that we can reuse the buffer.
+  fd_t fd = openrv;
+  // Fill the file with kShadowRodata.
+  const uptr kMarkerSize = 512 * 1024 / sizeof(u64);
+  InternalMmapVector<u64> marker(kMarkerSize);
+  // volatile to prevent insertion of memset
+  for (volatile u64 *p = marker.data(); p < marker.data() + kMarkerSize; p++)
+    *p = kShadowRodata;
+  internal_write(fd, marker.data(), marker.size() * sizeof(u64));
+  // Map the file into memory.
+  uptr page = internal_mmap(0, GetPageSizeCached(), PROT_READ | PROT_WRITE,
+                            MAP_PRIVATE | MAP_ANONYMOUS, fd, 0);
+  if (internal_iserror(page)) {
+    internal_close(fd);
+    return;
+  }
+  // Map the file into shadow of .rodata sections.
+  MemoryMappingLayout proc_maps(/*cache_enabled*/true);
+  // Reusing the buffer 'name'.
+  MemoryMappedSegment segment(name, ARRAY_SIZE(name));
+  while (proc_maps.Next(&segment)) {
+    if (segment.filename[0] != 0 && segment.filename[0] != '[' &&
+        segment.IsReadable() && segment.IsExecutable() &&
+        !segment.IsWritable() && IsAppMem(segment.start)) {
+      // Assume it's .rodata
+      char *shadow_start = (char *)MemToShadow(segment.start);
+      char *shadow_end = (char *)MemToShadow(segment.end);
+      for (char *p = shadow_start; p < shadow_end;
+           p += marker.size() * sizeof(u64)) {
+        internal_mmap(p, Min<uptr>(marker.size() * sizeof(u64), shadow_end - p),
+                      PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, 0);
+      }
+    }
+  }
+  internal_close(fd);
+}
+
+void InitializeShadowMemoryPlatform() {
+  MapRodata();
+}
+
+#endif  // #if !SANITIZER_GO
+
+void InitializePlatformEarly() {
+#ifdef TSAN_RUNTIME_VMA
+  vmaSize =
+    (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1);
+#if defined(__aarch64__)
+# if !SANITIZER_GO
+  if (vmaSize != 39 && vmaSize != 42 && vmaSize != 48) {
+    Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
+    Printf("FATAL: Found %zd - Supported 39, 42 and 48\n", vmaSize);
+    Die();
+  }
+#else
+  if (vmaSize != 48) {
+    Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
+    Printf("FATAL: Found %zd - Supported 48\n", vmaSize);
+    Die();
+  }
+#endif
+#elif defined(__powerpc64__)
+# if !SANITIZER_GO
+  if (vmaSize != 44 && vmaSize != 46 && vmaSize != 47) {
+    Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
+    Printf("FATAL: Found %zd - Supported 44, 46, and 47\n", vmaSize);
+    Die();
+  }
+# else
+  if (vmaSize != 46 && vmaSize != 47) {
+    Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
+    Printf("FATAL: Found %zd - Supported 46, and 47\n", vmaSize);
+    Die();
+  }
+# endif
+#endif
+#endif
+}
+
+void InitializePlatform() {
+  DisableCoreDumperIfNecessary();
+
+  // Go maps shadow memory lazily and works fine with limited address space.
+  // Unlimited stack is not a problem as well, because the executable
+  // is not compiled with -pie.
+#if !SANITIZER_GO
+  {
+    bool reexec = false;
+    // TSan doesn't play well with unlimited stack size (as stack
+    // overlaps with shadow memory). If we detect unlimited stack size,
+    // we re-exec the program with limited stack size as a best effort.
+    if (StackSizeIsUnlimited()) {
+      const uptr kMaxStackSize = 32 * 1024 * 1024;
+      VReport(1, "Program is run with unlimited stack size, which wouldn't "
+                 "work with ThreadSanitizer.\n"
+                 "Re-execing with stack size limited to %zd bytes.\n",
+              kMaxStackSize);
+      SetStackSizeLimitInBytes(kMaxStackSize);
+      reexec = true;
+    }
+
+    if (!AddressSpaceIsUnlimited()) {
+      Report("WARNING: Program is run with limited virtual address space,"
+             " which wouldn't work with ThreadSanitizer.\n");
+      Report("Re-execing with unlimited virtual address space.\n");
+      SetAddressSpaceUnlimited();
+      reexec = true;
+    }
+#if SANITIZER_LINUX && defined(__aarch64__)
+    // After patch "arm64: mm: support ARCH_MMAP_RND_BITS." is introduced in
+    // linux kernel, the random gap between stack and mapped area is increased
+    // from 128M to 36G on 39-bit aarch64. As it is almost impossible to cover
+    // this big range, we should disable randomized virtual space on aarch64.
+    int old_personality = personality(0xffffffff);
+    if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) {
+      VReport(1, "WARNING: Program is run with randomized virtual address "
+              "space, which wouldn't work with ThreadSanitizer.\n"
+              "Re-execing with fixed virtual address space.\n");
+      CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1);
+      reexec = true;
+    }
+    // Initialize the xor key used in {sig}{set,long}jump.
+    InitializeLongjmpXorKey();
+#endif
+    if (reexec)
+      ReExec();
+  }
+
+  CheckAndProtect();
+  InitTlsSize();
+#endif  // !SANITIZER_GO
+}
+
+#if !SANITIZER_GO
+// Extract file descriptors passed to glibc internal __res_iclose function.
+// This is required to properly "close" the fds, because we do not see internal
+// closes within glibc. The code is a pure hack.
+int ExtractResolvFDs(void *state, int *fds, int nfd) {
+#if SANITIZER_LINUX && !SANITIZER_ANDROID
+  int cnt = 0;
+  struct __res_state *statp = (struct __res_state*)state;
+  for (int i = 0; i < MAXNS && cnt < nfd; i++) {
+    if (statp->_u._ext.nsaddrs[i] && statp->_u._ext.nssocks[i] != -1)
+      fds[cnt++] = statp->_u._ext.nssocks[i];
+  }
+  return cnt;
+#else
+  return 0;
+#endif
+}
+
+// Extract file descriptors passed via UNIX domain sockets.
+// This is requried to properly handle "open" of these fds.
+// see 'man recvmsg' and 'man 3 cmsg'.
+int ExtractRecvmsgFDs(void *msgp, int *fds, int nfd) {
+  int res = 0;
+  msghdr *msg = (msghdr*)msgp;
+  struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg);
+  for (; cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
+    if (cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS)
+      continue;
+    int n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(fds[0]);
+    for (int i = 0; i < n; i++) {
+      fds[res++] = ((int*)CMSG_DATA(cmsg))[i];
+      if (res == nfd)
+        return res;
+    }
+  }
+  return res;
+}
+
+// Reverse operation of libc stack pointer mangling
+static uptr UnmangleLongJmpSp(uptr mangled_sp) {
+#if defined(__x86_64__)
+# if SANITIZER_LINUX
+  // Reverse of:
+  //   xor  %fs:0x30, %rsi
+  //   rol  $0x11, %rsi
+  uptr sp;
+  asm("ror  $0x11,     %0 \n"
+      "xor  %%fs:0x30, %0 \n"
+      : "=r" (sp)
+      : "0" (mangled_sp));
+  return sp;
+# else
+  return mangled_sp;
+# endif
+#elif defined(__aarch64__)
+# if SANITIZER_LINUX
+  return mangled_sp ^ longjmp_xor_key;
+# else
+  return mangled_sp;
+# endif
+#elif defined(__powerpc64__)
+  // Reverse of:
+  //   ld   r4, -28696(r13)
+  //   xor  r4, r3, r4
+  uptr xor_key;
+  asm("ld  %0, -28696(%%r13)" : "=r" (xor_key));
+  return mangled_sp ^ xor_key;
+#elif defined(__mips__)
+  return mangled_sp;
+#else
+  #error "Unknown platform"
+#endif
+}
+
+#ifdef __powerpc__
+# define LONG_JMP_SP_ENV_SLOT 0
+#elif SANITIZER_FREEBSD
+# define LONG_JMP_SP_ENV_SLOT 2
+#elif SANITIZER_NETBSD
+# define LONG_JMP_SP_ENV_SLOT 6
+#elif SANITIZER_LINUX
+# ifdef __aarch64__
+#  define LONG_JMP_SP_ENV_SLOT 13
+# elif defined(__mips64)
+#  define LONG_JMP_SP_ENV_SLOT 1
+# else
+#  define LONG_JMP_SP_ENV_SLOT 6
+# endif
+#endif
+
+uptr ExtractLongJmpSp(uptr *env) {
+  uptr mangled_sp = env[LONG_JMP_SP_ENV_SLOT];
+  return UnmangleLongJmpSp(mangled_sp);
+}
+
+#if INIT_LONGJMP_XOR_KEY
+// GLIBC mangles the function pointers in jmp_buf (used in {set,long}*jmp
+// functions) by XORing them with a random key.  For AArch64 it is a global
+// variable rather than a TCB one (as for x86_64/powerpc).  We obtain the key by
+// issuing a setjmp and XORing the SP pointer values to derive the key.
+static void InitializeLongjmpXorKey() {
+  // 1. Call REAL(setjmp), which stores the mangled SP in env.
+  jmp_buf env;
+  REAL(_setjmp)(env);
+
+  // 2. Retrieve vanilla/mangled SP.
+  uptr sp;
+  asm("mov  %0, sp" : "=r" (sp));
+  uptr mangled_sp = ((uptr *)&env)[LONG_JMP_SP_ENV_SLOT];
+
+  // 3. xor SPs to obtain key.
+  longjmp_xor_key = mangled_sp ^ sp;
+}
+#endif
+
+void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size) {
+  // Check that the thr object is in tls;
+  const uptr thr_beg = (uptr)thr;
+  const uptr thr_end = (uptr)thr + sizeof(*thr);
+  CHECK_GE(thr_beg, tls_addr);
+  CHECK_LE(thr_beg, tls_addr + tls_size);
+  CHECK_GE(thr_end, tls_addr);
+  CHECK_LE(thr_end, tls_addr + tls_size);
+  // Since the thr object is huge, skip it.
+  MemoryRangeImitateWrite(thr, /*pc=*/2, tls_addr, thr_beg - tls_addr);
+  MemoryRangeImitateWrite(thr, /*pc=*/2, thr_end,
+                          tls_addr + tls_size - thr_end);
+}
+
+// Note: this function runs with async signals enabled,
+// so it must not touch any tsan state.
+int call_pthread_cancel_with_cleanup(int(*fn)(void *c, void *m,
+    void *abstime), void *c, void *m, void *abstime,
+    void(*cleanup)(void *arg), void *arg) {
+  // pthread_cleanup_push/pop are hardcore macros mess.
+  // We can't intercept nor call them w/o including pthread.h.
+  int res;
+  pthread_cleanup_push(cleanup, arg);
+  res = fn(c, m, abstime);
+  pthread_cleanup_pop(0);
+  return res;
+}
+#endif  // !SANITIZER_GO
+
+#if !SANITIZER_GO
+void ReplaceSystemMalloc() { }
+#endif
+
+#if !SANITIZER_GO
+#if SANITIZER_ANDROID
+// On Android, one thread can call intercepted functions after
+// DestroyThreadState(), so add a fake thread state for "dead" threads.
+static ThreadState *dead_thread_state = nullptr;
+
+ThreadState *cur_thread() {
+  ThreadState* thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
+  if (thr == nullptr) {
+    __sanitizer_sigset_t emptyset;
+    internal_sigfillset(&emptyset);
+    __sanitizer_sigset_t oldset;
+    CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &emptyset, &oldset));
+    thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
+    if (thr == nullptr) {
+      thr = reinterpret_cast<ThreadState*>(MmapOrDie(sizeof(ThreadState),
+                                                     "ThreadState"));
+      *get_android_tls_ptr() = reinterpret_cast<uptr>(thr);
+      if (dead_thread_state == nullptr) {
+        dead_thread_state = reinterpret_cast<ThreadState*>(
+            MmapOrDie(sizeof(ThreadState), "ThreadState"));
+        dead_thread_state->fast_state.SetIgnoreBit();
+        dead_thread_state->ignore_interceptors = 1;
+        dead_thread_state->is_dead = true;
+        *const_cast<int*>(&dead_thread_state->tid) = -1;
+        CHECK_EQ(0, internal_mprotect(dead_thread_state, sizeof(ThreadState),
+                                      PROT_READ));
+      }
+    }
+    CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &oldset, nullptr));
+  }
+  return thr;
+}
+
+void set_cur_thread(ThreadState *thr) {
+  *get_android_tls_ptr() = reinterpret_cast<uptr>(thr);
+}
+
+void cur_thread_finalize() {
+  __sanitizer_sigset_t emptyset;
+  internal_sigfillset(&emptyset);
+  __sanitizer_sigset_t oldset;
+  CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &emptyset, &oldset));
+  ThreadState* thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
+  if (thr != dead_thread_state) {
+    *get_android_tls_ptr() = reinterpret_cast<uptr>(dead_thread_state);
+    UnmapOrDie(thr, sizeof(ThreadState));
+  }
+  CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &oldset, nullptr));
+}
+#endif  // SANITIZER_ANDROID
+#endif  // if !SANITIZER_GO
+
+}  // namespace __tsan
+
+#endif  // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD