libsanitizer/tsan/tsan_platform_linux.cc

   1 //===-- tsan_platform_linux.cc --------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of ThreadSanitizer (TSan), a race detector.
   9 //
  10 // Linux- and FreeBSD-specific code.
  11 //===----------------------------------------------------------------------===//
  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_stoptheworld.h"
  25 #include "sanitizer_common/sanitizer_stackdepot.h"
  26 #include "tsan_platform.h"
  27 #include "tsan_rtl.h"
  28 #include "tsan_flags.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
  65 extern "C" void *__libc_stack_end;
  66 void *__libc_stack_end = 0;
  67 #endif
  68
  69 #if SANITIZER_LINUX && defined(__aarch64__)
  70 void InitializeGuardPtr() __attribute__((visibility("hidden")));
  71 #endif
  72
  73 namespace __tsan {
  74
  75 #ifdef TSAN_RUNTIME_VMA
  76 // Runtime detected VMA size.
  77 uptr vmaSize;
  78 #endif
  79
  80 enum {
  81   MemTotal  = 0,
  82   MemShadow = 1,
  83   MemMeta   = 2,
  84   MemFile   = 3,
  85   MemMmap   = 4,
  86   MemTrace  = 5,
  87   MemHeap   = 6,
  88   MemOther  = 7,
  89   MemCount  = 8,
  90 };
  91
  92 void FillProfileCallback(uptr p, uptr rss, bool file,
  93                          uptr *mem, uptr stats_size) {
  94   mem[MemTotal] += rss;
  95   if (p >= ShadowBeg() && p < ShadowEnd())
  96     mem[MemShadow] += rss;
  97   else if (p >= MetaShadowBeg() && p < MetaShadowEnd())
  98     mem[MemMeta] += rss;
  99 #if !SANITIZER_GO
 100   else if (p >= HeapMemBeg() && p < HeapMemEnd())
 101     mem[MemHeap] += rss;
 102   else if (p >= LoAppMemBeg() && p < LoAppMemEnd())
 103     mem[file ? MemFile : MemMmap] += rss;
 104   else if (p >= HiAppMemBeg() && p < HiAppMemEnd())
 105     mem[file ? MemFile : MemMmap] += rss;
 106 #else
 107   else if (p >= AppMemBeg() && p < AppMemEnd())
 108     mem[file ? MemFile : MemMmap] += rss;
 109 #endif
 110   else if (p >= TraceMemBeg() && p < TraceMemEnd())
 111     mem[MemTrace] += rss;
 112   else
 113     mem[MemOther] += rss;
 114 }
 115
 116 void WriteMemoryProfile(char *buf, uptr buf_size, uptr nthread, uptr nlive) {
 117   uptr mem[MemCount];
 118   internal_memset(mem, 0, sizeof(mem[0]) * MemCount);
 119   __sanitizer::GetMemoryProfile(FillProfileCallback, mem, 7);
 120   StackDepotStats *stacks = StackDepotGetStats();
 121   internal_snprintf(buf, buf_size,
 122       "RSS %zd MB: shadow:%zd meta:%zd file:%zd mmap:%zd"
 123       " trace:%zd heap:%zd other:%zd stacks=%zd[%zd] nthr=%zd/%zd\n",
 124       mem[MemTotal] >> 20, mem[MemShadow] >> 20, mem[MemMeta] >> 20,
 125       mem[MemFile] >> 20, mem[MemMmap] >> 20, mem[MemTrace] >> 20,
 126       mem[MemHeap] >> 20, mem[MemOther] >> 20,
 127       stacks->allocated >> 20, stacks->n_uniq_ids,
 128       nlive, nthread);
 129 }
 130
 131 #if SANITIZER_LINUX
 132 void FlushShadowMemoryCallback(
 133     const SuspendedThreadsList &suspended_threads_list,
 134     void *argument) {
 135   ReleaseMemoryPagesToOS(ShadowBeg(), ShadowEnd());
 136 }
 137 #endif
 138
 139 void FlushShadowMemory() {
 140 #if SANITIZER_LINUX
 141   StopTheWorld(FlushShadowMemoryCallback, 0);
 142 #endif
 143 }
 144
 145 #if !SANITIZER_GO
 146 // Mark shadow for .rodata sections with the special kShadowRodata marker.
 147 // Accesses to .rodata can't race, so this saves time, memory and trace space.
 148 static void MapRodata() {
 149   // First create temp file.
 150   const char *tmpdir = GetEnv("TMPDIR");
 151   if (tmpdir == 0)
 152     tmpdir = GetEnv("TEST_TMPDIR");
 153 #ifdef P_tmpdir
 154   if (tmpdir == 0)
 155     tmpdir = P_tmpdir;
 156 #endif
 157   if (tmpdir == 0)
 158     return;
 159   char name[256];
 160   internal_snprintf(name, sizeof(name), "%s/tsan.rodata.%d",
 161                     tmpdir, (int)internal_getpid());
 162   uptr openrv = internal_open(name, O_RDWR | O_CREAT | O_EXCL, 0600);
 163   if (internal_iserror(openrv))
 164     return;
 165   internal_unlink(name);  // Unlink it now, so that we can reuse the buffer.
 166   fd_t fd = openrv;
 167   // Fill the file with kShadowRodata.
 168   const uptr kMarkerSize = 512 * 1024 / sizeof(u64);
 169   InternalMmapVector<u64> marker(kMarkerSize);
 170   // volatile to prevent insertion of memset
 171   for (volatile u64 *p = marker.data(); p < marker.data() + kMarkerSize; p++)
 172     *p = kShadowRodata;
 173   internal_write(fd, marker.data(), marker.size() * sizeof(u64));
 174   // Map the file into memory.
 175   uptr page = internal_mmap(0, GetPageSizeCached(), PROT_READ | PROT_WRITE,
 176                             MAP_PRIVATE | MAP_ANONYMOUS, fd, 0);
 177   if (internal_iserror(page)) {
 178     internal_close(fd);
 179     return;
 180   }
 181   // Map the file into shadow of .rodata sections.
 182   MemoryMappingLayout proc_maps(/*cache_enabled*/true);
 183   // Reusing the buffer 'name'.
 184   MemoryMappedSegment segment(name, ARRAY_SIZE(name));
 185   while (proc_maps.Next(&segment)) {
 186     if (segment.filename[0] != 0 && segment.filename[0] != '[' &&
 187         segment.IsReadable() && segment.IsExecutable() &&
 188         !segment.IsWritable() && IsAppMem(segment.start)) {
 189       // Assume it's .rodata
 190       char *shadow_start = (char *)MemToShadow(segment.start);
 191       char *shadow_end = (char *)MemToShadow(segment.end);
 192       for (char *p = shadow_start; p < shadow_end;
 193            p += marker.size() * sizeof(u64)) {
 194         internal_mmap(p, Min<uptr>(marker.size() * sizeof(u64), shadow_end - p),
 195                       PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, 0);
 196       }
 197     }
 198   }
 199   internal_close(fd);
 200 }
 201
 202 void InitializeShadowMemoryPlatform() {
 203   MapRodata();
 204 }
 205
 206 #endif  // #if !SANITIZER_GO
 207
 208 void InitializePlatformEarly() {
 209 #ifdef TSAN_RUNTIME_VMA
 210   vmaSize =
 211     (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1);
 212 #if defined(__aarch64__)
 213 # if !SANITIZER_GO
 214   if (vmaSize != 39 && vmaSize != 42 && vmaSize != 48) {
 215     Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
 216     Printf("FATAL: Found %zd - Supported 39, 42 and 48\n", vmaSize);
 217     Die();
 218   }
 219 #else
 220   if (vmaSize != 48) {
 221     Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
 222     Printf("FATAL: Found %zd - Supported 48\n", vmaSize);
 223     Die();
 224   }
 225 #endif
 226 #elif defined(__powerpc64__)
 227 # if !SANITIZER_GO
 228   if (vmaSize != 44 && vmaSize != 46 && vmaSize != 47) {
 229     Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
 230     Printf("FATAL: Found %zd - Supported 44, 46, and 47\n", vmaSize);
 231     Die();
 232   }
 233 # else
 234   if (vmaSize != 46 && vmaSize != 47) {
 235     Printf("FATAL: ThreadSanitizer: unsupported VMA range\n");
 236     Printf("FATAL: Found %zd - Supported 46, and 47\n", vmaSize);
 237     Die();
 238   }
 239 # endif
 240 #endif
 241 #endif
 242 }
 243
 244 void InitializePlatform() {
 245   DisableCoreDumperIfNecessary();
 246
 247   // Go maps shadow memory lazily and works fine with limited address space.
 248   // Unlimited stack is not a problem as well, because the executable
 249   // is not compiled with -pie.
 250   if (!SANITIZER_GO) {
 251     bool reexec = false;
 252     // TSan doesn't play well with unlimited stack size (as stack
 253     // overlaps with shadow memory). If we detect unlimited stack size,
 254     // we re-exec the program with limited stack size as a best effort.
 255     if (StackSizeIsUnlimited()) {
 256       const uptr kMaxStackSize = 32 * 1024 * 1024;
 257       VReport(1, "Program is run with unlimited stack size, which wouldn't "
 258                  "work with ThreadSanitizer.\n"
 259                  "Re-execing with stack size limited to %zd bytes.\n",
 260               kMaxStackSize);
 261       SetStackSizeLimitInBytes(kMaxStackSize);
 262       reexec = true;
 263     }
 264
 265     if (!AddressSpaceIsUnlimited()) {
 266       Report("WARNING: Program is run with limited virtual address space,"
 267              " which wouldn't work with ThreadSanitizer.\n");
 268       Report("Re-execing with unlimited virtual address space.\n");
 269       SetAddressSpaceUnlimited();
 270       reexec = true;
 271     }
 272 #if SANITIZER_LINUX && defined(__aarch64__)
 273     // After patch "arm64: mm: support ARCH_MMAP_RND_BITS." is introduced in
 274     // linux kernel, the random gap between stack and mapped area is increased
 275     // from 128M to 36G on 39-bit aarch64. As it is almost impossible to cover
 276     // this big range, we should disable randomized virtual space on aarch64.
 277     int old_personality = personality(0xffffffff);
 278     if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) {
 279       VReport(1, "WARNING: Program is run with randomized virtual address "
 280               "space, which wouldn't work with ThreadSanitizer.\n"
 281               "Re-execing with fixed virtual address space.\n");
 282       CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1);
 283       reexec = true;
 284     }
 285     // Initialize the guard pointer used in {sig}{set,long}jump.
 286     InitializeGuardPtr();
 287 #endif
 288     if (reexec)
 289       ReExec();
 290   }
 291
 292 #if !SANITIZER_GO
 293   CheckAndProtect();
 294   InitTlsSize();
 295 #endif
 296 }
 297
 298 #if !SANITIZER_GO
 299 // Extract file descriptors passed to glibc internal __res_iclose function.
 300 // This is required to properly "close" the fds, because we do not see internal
 301 // closes within glibc. The code is a pure hack.
 302 int ExtractResolvFDs(void *state, int *fds, int nfd) {
 303 #if SANITIZER_LINUX && !SANITIZER_ANDROID
 304   int cnt = 0;
 305   struct __res_state *statp = (struct __res_state*)state;
 306   for (int i = 0; i < MAXNS && cnt < nfd; i++) {
 307     if (statp->_u._ext.nsaddrs[i] && statp->_u._ext.nssocks[i] != -1)
 308       fds[cnt++] = statp->_u._ext.nssocks[i];
 309   }
 310   return cnt;
 311 #else
 312   return 0;
 313 #endif
 314 }
 315
 316 // Extract file descriptors passed via UNIX domain sockets.
 317 // This is requried to properly handle "open" of these fds.
 318 // see 'man recvmsg' and 'man 3 cmsg'.
 319 int ExtractRecvmsgFDs(void *msgp, int *fds, int nfd) {
 320   int res = 0;
 321   msghdr *msg = (msghdr*)msgp;
 322   struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg);
 323   for (; cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 324     if (cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS)
 325       continue;
 326     int n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(fds[0]);
 327     for (int i = 0; i < n; i++) {
 328       fds[res++] = ((int*)CMSG_DATA(cmsg))[i];
 329       if (res == nfd)
 330         return res;
 331     }
 332   }
 333   return res;
 334 }
 335
 336 void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size) {
 337   // Check that the thr object is in tls;
 338   const uptr thr_beg = (uptr)thr;
 339   const uptr thr_end = (uptr)thr + sizeof(*thr);
 340   CHECK_GE(thr_beg, tls_addr);
 341   CHECK_LE(thr_beg, tls_addr + tls_size);
 342   CHECK_GE(thr_end, tls_addr);
 343   CHECK_LE(thr_end, tls_addr + tls_size);
 344   // Since the thr object is huge, skip it.
 345   MemoryRangeImitateWrite(thr, /*pc=*/2, tls_addr, thr_beg - tls_addr);
 346   MemoryRangeImitateWrite(thr, /*pc=*/2, thr_end,
 347                           tls_addr + tls_size - thr_end);
 348 }
 349
 350 // Note: this function runs with async signals enabled,
 351 // so it must not touch any tsan state.
 352 int call_pthread_cancel_with_cleanup(int(*fn)(void *c, void *m,
 353     void *abstime), void *c, void *m, void *abstime,
 354     void(*cleanup)(void *arg), void *arg) {
 355   // pthread_cleanup_push/pop are hardcore macros mess.
 356   // We can't intercept nor call them w/o including pthread.h.
 357   int res;
 358   pthread_cleanup_push(cleanup, arg);
 359   res = fn(c, m, abstime);
 360   pthread_cleanup_pop(0);
 361   return res;
 362 }
 363 #endif
 364
 365 #if !SANITIZER_GO
 366 void ReplaceSystemMalloc() { }
 367 #endif
 368
 369 #if !SANITIZER_GO
 370 #if SANITIZER_ANDROID
 371 // On Android, one thread can call intercepted functions after
 372 // DestroyThreadState(), so add a fake thread state for "dead" threads.
 373 static ThreadState *dead_thread_state = nullptr;
 374
 375 ThreadState *cur_thread() {
 376   ThreadState* thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
 377   if (thr == nullptr) {
 378     __sanitizer_sigset_t emptyset;
 379     internal_sigfillset(&emptyset);
 380     __sanitizer_sigset_t oldset;
 381     CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &emptyset, &oldset));
 382     thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
 383     if (thr == nullptr) {
 384       thr = reinterpret_cast<ThreadState*>(MmapOrDie(sizeof(ThreadState),
 385                                                      "ThreadState"));
 386       *get_android_tls_ptr() = reinterpret_cast<uptr>(thr);
 387       if (dead_thread_state == nullptr) {
 388         dead_thread_state = reinterpret_cast<ThreadState*>(
 389             MmapOrDie(sizeof(ThreadState), "ThreadState"));
 390         dead_thread_state->fast_state.SetIgnoreBit();
 391         dead_thread_state->ignore_interceptors = 1;
 392         dead_thread_state->is_dead = true;
 393         *const_cast<int*>(&dead_thread_state->tid) = -1;
 394         CHECK_EQ(0, internal_mprotect(dead_thread_state, sizeof(ThreadState),
 395                                       PROT_READ));
 396       }
 397     }
 398     CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &oldset, nullptr));
 399   }
 400   return thr;
 401 }
 402
 403 void cur_thread_finalize() {
 404   __sanitizer_sigset_t emptyset;
 405   internal_sigfillset(&emptyset);
 406   __sanitizer_sigset_t oldset;
 407   CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &emptyset, &oldset));
 408   ThreadState* thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr());
 409   if (thr != dead_thread_state) {
 410     *get_android_tls_ptr() = reinterpret_cast<uptr>(dead_thread_state);
 411     UnmapOrDie(thr, sizeof(ThreadState));
 412   }
 413   CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &oldset, nullptr));
 414 }
 415 #endif  // SANITIZER_ANDROID
 416 #endif  // if !SANITIZER_GO
 417
 418 }  // namespace __tsan
 419
 420 #endif  // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD