1//===-- tsan_platform_linux.cc --------------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file is a part of ThreadSanitizer (TSan), a race detector. 11// 12// Linux- and FreeBSD-specific code. 13//===----------------------------------------------------------------------===// 14 15 16#include "sanitizer_common/sanitizer_platform.h" 17#if SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD 18 19#include "sanitizer_common/sanitizer_common.h" 20#include "sanitizer_common/sanitizer_libc.h" 21#include "sanitizer_common/sanitizer_linux.h" 22#include "sanitizer_common/sanitizer_platform_limits_netbsd.h" 23#include "sanitizer_common/sanitizer_platform_limits_posix.h" 24#include "sanitizer_common/sanitizer_posix.h" 25#include "sanitizer_common/sanitizer_procmaps.h" 26#include "sanitizer_common/sanitizer_stoptheworld.h" 27#include "sanitizer_common/sanitizer_stackdepot.h" 28#include "tsan_platform.h" 29#include "tsan_rtl.h" 30#include "tsan_flags.h" 31 32#include <fcntl.h> 33#include <pthread.h> 34#include <signal.h> 35#include <stdio.h> 36#include <stdlib.h> 37#include <string.h> 38#include <stdarg.h> 39#include <sys/mman.h> 40#if SANITIZER_LINUX 41#include <sys/personality.h> 42#include <setjmp.h> 43#endif 44#include <sys/syscall.h> 45#include <sys/socket.h> 46#include <sys/time.h> 47#include <sys/types.h> 48#include <sys/resource.h> 49#include <sys/stat.h> 50#include <unistd.h> 51#include <sched.h> 52#include <dlfcn.h> 53#if SANITIZER_LINUX 54#define __need_res_state 55#include <resolv.h> 56#endif 57 58#ifdef sa_handler 59# undef sa_handler 60#endif 61 62#ifdef sa_sigaction 63# undef sa_sigaction 64#endif 65 66#if SANITIZER_FREEBSD 67extern "C" void *__libc_stack_end; 68void *__libc_stack_end = 0; 69#endif 70 71#if SANITIZER_LINUX && defined(__aarch64__) 72void InitializeGuardPtr() __attribute__((visibility("hidden"))); 73#endif 74 75namespace __tsan { 76 77#ifdef TSAN_RUNTIME_VMA 78// Runtime detected VMA size. 79uptr vmaSize; 80#endif 81 82enum { 83 MemTotal = 0, 84 MemShadow = 1, 85 MemMeta = 2, 86 MemFile = 3, 87 MemMmap = 4, 88 MemTrace = 5, 89 MemHeap = 6, 90 MemOther = 7, 91 MemCount = 8, 92}; 93 94void FillProfileCallback(uptr p, uptr rss, bool file, 95 uptr *mem, uptr stats_size) { 96 mem[MemTotal] += rss; 97 if (p >= ShadowBeg() && p < ShadowEnd()) 98 mem[MemShadow] += rss; 99 else if (p >= MetaShadowBeg() && p < MetaShadowEnd()) 100 mem[MemMeta] += rss; 101#if !SANITIZER_GO 102 else if (p >= HeapMemBeg() && p < HeapMemEnd()) 103 mem[MemHeap] += rss; 104 else if (p >= LoAppMemBeg() && p < LoAppMemEnd()) 105 mem[file ? MemFile : MemMmap] += rss; 106 else if (p >= HiAppMemBeg() && p < HiAppMemEnd()) 107 mem[file ? MemFile : MemMmap] += rss; 108#else 109 else if (p >= AppMemBeg() && p < AppMemEnd()) 110 mem[file ? MemFile : MemMmap] += rss; 111#endif 112 else if (p >= TraceMemBeg() && p < TraceMemEnd()) 113 mem[MemTrace] += rss; 114 else 115 mem[MemOther] += rss; 116} 117 118void WriteMemoryProfile(char *buf, uptr buf_size, uptr nthread, uptr nlive) { 119 uptr mem[MemCount]; 120 internal_memset(mem, 0, sizeof(mem[0]) * MemCount); 121 __sanitizer::GetMemoryProfile(FillProfileCallback, mem, 7); 122 StackDepotStats *stacks = StackDepotGetStats(); 123 internal_snprintf(buf, buf_size, 124 "RSS %zd MB: shadow:%zd meta:%zd file:%zd mmap:%zd" 125 " trace:%zd heap:%zd other:%zd stacks=%zd[%zd] nthr=%zd/%zd\n", 126 mem[MemTotal] >> 20, mem[MemShadow] >> 20, mem[MemMeta] >> 20, 127 mem[MemFile] >> 20, mem[MemMmap] >> 20, mem[MemTrace] >> 20, 128 mem[MemHeap] >> 20, mem[MemOther] >> 20, 129 stacks->allocated >> 20, stacks->n_uniq_ids, 130 nlive, nthread); 131} 132 133#if SANITIZER_LINUX 134void FlushShadowMemoryCallback( 135 const SuspendedThreadsList &suspended_threads_list, 136 void *argument) { 137 ReleaseMemoryPagesToOS(ShadowBeg(), ShadowEnd()); 138} 139#endif 140 141void FlushShadowMemory() { 142#if SANITIZER_LINUX 143 StopTheWorld(FlushShadowMemoryCallback, 0); 144#endif 145} 146 147#if !SANITIZER_GO 148// Mark shadow for .rodata sections with the special kShadowRodata marker. 149// Accesses to .rodata can't race, so this saves time, memory and trace space. 150static void MapRodata() { 151 // First create temp file. 152 const char *tmpdir = GetEnv("TMPDIR"); 153 if (tmpdir == 0) 154 tmpdir = GetEnv("TEST_TMPDIR"); 155#ifdef P_tmpdir 156 if (tmpdir == 0) 157 tmpdir = P_tmpdir; 158#endif 159 if (tmpdir == 0) 160 return; 161 char name[256]; 162 internal_snprintf(name, sizeof(name), "%s/tsan.rodata.%d", 163 tmpdir, (int)internal_getpid()); 164 uptr openrv = internal_open(name, O_RDWR | O_CREAT | O_EXCL, 0600); 165 if (internal_iserror(openrv)) 166 return; 167 internal_unlink(name); // Unlink it now, so that we can reuse the buffer. 168 fd_t fd = openrv; 169 // Fill the file with kShadowRodata. 170 const uptr kMarkerSize = 512 * 1024 / sizeof(u64); 171 InternalMmapVector<u64> marker(kMarkerSize); 172 // volatile to prevent insertion of memset 173 for (volatile u64 *p = marker.data(); p < marker.data() + kMarkerSize; p++) 174 *p = kShadowRodata; 175 internal_write(fd, marker.data(), marker.size() * sizeof(u64)); 176 // Map the file into memory. 177 uptr page = internal_mmap(0, GetPageSizeCached(), PROT_READ | PROT_WRITE, 178 MAP_PRIVATE | MAP_ANONYMOUS, fd, 0); 179 if (internal_iserror(page)) { 180 internal_close(fd); 181 return; 182 } 183 // Map the file into shadow of .rodata sections. 184 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 185 // Reusing the buffer 'name'. 186 MemoryMappedSegment segment(name, ARRAY_SIZE(name)); 187 while (proc_maps.Next(&segment)) { 188 if (segment.filename[0] != 0 && segment.filename[0] != '[' && 189 segment.IsReadable() && segment.IsExecutable() && 190 !segment.IsWritable() && IsAppMem(segment.start)) { 191 // Assume it's .rodata 192 char *shadow_start = (char *)MemToShadow(segment.start); 193 char *shadow_end = (char *)MemToShadow(segment.end); 194 for (char *p = shadow_start; p < shadow_end; 195 p += marker.size() * sizeof(u64)) { 196 internal_mmap(p, Min<uptr>(marker.size() * sizeof(u64), shadow_end - p), 197 PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, 0); 198 } 199 } 200 } 201 internal_close(fd); 202} 203 204void InitializeShadowMemoryPlatform() { 205 MapRodata(); 206} 207 208#endif // #if !SANITIZER_GO 209 210void InitializePlatformEarly() { 211#ifdef TSAN_RUNTIME_VMA 212 vmaSize = 213 (MostSignificantSetBitIndex(GET_CURRENT_FRAME()) + 1); 214#if defined(__aarch64__) 215# if !SANITIZER_GO 216 if (vmaSize != 39 && vmaSize != 42 && vmaSize != 48) { 217 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n"); 218 Printf("FATAL: Found %zd - Supported 39, 42 and 48\n", vmaSize); 219 Die(); 220 } 221#else 222 if (vmaSize != 48) { 223 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n"); 224 Printf("FATAL: Found %zd - Supported 48\n", vmaSize); 225 Die(); 226 } 227#endif 228#elif defined(__powerpc64__) 229# if !SANITIZER_GO 230 if (vmaSize != 44 && vmaSize != 46 && vmaSize != 47) { 231 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n"); 232 Printf("FATAL: Found %zd - Supported 44, 46, and 47\n", vmaSize); 233 Die(); 234 } 235# else 236 if (vmaSize != 46 && vmaSize != 47) { 237 Printf("FATAL: ThreadSanitizer: unsupported VMA range\n"); 238 Printf("FATAL: Found %zd - Supported 46, and 47\n", vmaSize); 239 Die(); 240 } 241# endif 242#endif 243#endif 244} 245 246void InitializePlatform() { 247 DisableCoreDumperIfNecessary(); 248 249 // Go maps shadow memory lazily and works fine with limited address space. 250 // Unlimited stack is not a problem as well, because the executable 251 // is not compiled with -pie. 252 if (!SANITIZER_GO) { 253 bool reexec = false; 254 // TSan doesn't play well with unlimited stack size (as stack 255 // overlaps with shadow memory). If we detect unlimited stack size, 256 // we re-exec the program with limited stack size as a best effort. 257 if (StackSizeIsUnlimited()) { 258 const uptr kMaxStackSize = 32 * 1024 * 1024; 259 VReport(1, "Program is run with unlimited stack size, which wouldn't " 260 "work with ThreadSanitizer.\n" 261 "Re-execing with stack size limited to %zd bytes.\n", 262 kMaxStackSize); 263 SetStackSizeLimitInBytes(kMaxStackSize); 264 reexec = true; 265 } 266 267 if (!AddressSpaceIsUnlimited()) { 268 Report("WARNING: Program is run with limited virtual address space," 269 " which wouldn't work with ThreadSanitizer.\n"); 270 Report("Re-execing with unlimited virtual address space.\n"); 271 SetAddressSpaceUnlimited(); 272 reexec = true; 273 } 274#if SANITIZER_LINUX && defined(__aarch64__) 275 // After patch "arm64: mm: support ARCH_MMAP_RND_BITS." is introduced in 276 // linux kernel, the random gap between stack and mapped area is increased 277 // from 128M to 36G on 39-bit aarch64. As it is almost impossible to cover 278 // this big range, we should disable randomized virtual space on aarch64. 279 int old_personality = personality(0xffffffff); 280 if (old_personality != -1 && (old_personality & ADDR_NO_RANDOMIZE) == 0) { 281 VReport(1, "WARNING: Program is run with randomized virtual address " 282 "space, which wouldn't work with ThreadSanitizer.\n" 283 "Re-execing with fixed virtual address space.\n"); 284 CHECK_NE(personality(old_personality | ADDR_NO_RANDOMIZE), -1); 285 reexec = true; 286 } 287 // Initialize the guard pointer used in {sig}{set,long}jump. 288 InitializeGuardPtr(); 289#endif 290 if (reexec) 291 ReExec(); 292 } 293 294#if !SANITIZER_GO 295 CheckAndProtect(); 296 InitTlsSize(); 297#endif 298} 299 300#if !SANITIZER_GO 301// Extract file descriptors passed to glibc internal __res_iclose function. 302// This is required to properly "close" the fds, because we do not see internal 303// closes within glibc. The code is a pure hack. 304int ExtractResolvFDs(void *state, int *fds, int nfd) { 305#if SANITIZER_LINUX && !SANITIZER_ANDROID 306 int cnt = 0; 307 struct __res_state *statp = (struct __res_state*)state; 308 for (int i = 0; i < MAXNS && cnt < nfd; i++) { 309 if (statp->_u._ext.nsaddrs[i] && statp->_u._ext.nssocks[i] != -1) 310 fds[cnt++] = statp->_u._ext.nssocks[i]; 311 } 312 return cnt; 313#else 314 return 0; 315#endif 316} 317 318// Extract file descriptors passed via UNIX domain sockets. 319// This is requried to properly handle "open" of these fds. 320// see 'man recvmsg' and 'man 3 cmsg'. 321int ExtractRecvmsgFDs(void *msgp, int *fds, int nfd) { 322 int res = 0; 323 msghdr *msg = (msghdr*)msgp; 324 struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg); 325 for (; cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { 326 if (cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS) 327 continue; 328 int n = (cmsg->cmsg_len - CMSG_LEN(0)) / sizeof(fds[0]); 329 for (int i = 0; i < n; i++) { 330 fds[res++] = ((int*)CMSG_DATA(cmsg))[i]; 331 if (res == nfd) 332 return res; 333 } 334 } 335 return res; 336} 337 338void ImitateTlsWrite(ThreadState *thr, uptr tls_addr, uptr tls_size) { 339 // Check that the thr object is in tls; 340 const uptr thr_beg = (uptr)thr; 341 const uptr thr_end = (uptr)thr + sizeof(*thr); 342 CHECK_GE(thr_beg, tls_addr); 343 CHECK_LE(thr_beg, tls_addr + tls_size); 344 CHECK_GE(thr_end, tls_addr); 345 CHECK_LE(thr_end, tls_addr + tls_size); 346 // Since the thr object is huge, skip it. 347 MemoryRangeImitateWrite(thr, /*pc=*/2, tls_addr, thr_beg - tls_addr); 348 MemoryRangeImitateWrite(thr, /*pc=*/2, thr_end, 349 tls_addr + tls_size - thr_end); 350} 351 352// Note: this function runs with async signals enabled, 353// so it must not touch any tsan state. 354int call_pthread_cancel_with_cleanup(int(*fn)(void *c, void *m, 355 void *abstime), void *c, void *m, void *abstime, 356 void(*cleanup)(void *arg), void *arg) { 357 // pthread_cleanup_push/pop are hardcore macros mess. 358 // We can't intercept nor call them w/o including pthread.h. 359 int res; 360 pthread_cleanup_push(cleanup, arg); 361 res = fn(c, m, abstime); 362 pthread_cleanup_pop(0); 363 return res; 364} 365#endif 366 367#if !SANITIZER_GO 368void ReplaceSystemMalloc() { } 369#endif 370 371#if !SANITIZER_GO 372#if SANITIZER_ANDROID 373// On Android, one thread can call intercepted functions after 374// DestroyThreadState(), so add a fake thread state for "dead" threads. 375static ThreadState *dead_thread_state = nullptr; 376 377ThreadState *cur_thread() { 378 ThreadState* thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr()); 379 if (thr == nullptr) { 380 __sanitizer_sigset_t emptyset; 381 internal_sigfillset(&emptyset); 382 __sanitizer_sigset_t oldset; 383 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &emptyset, &oldset)); 384 thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr()); 385 if (thr == nullptr) { 386 thr = reinterpret_cast<ThreadState*>(MmapOrDie(sizeof(ThreadState), 387 "ThreadState")); 388 *get_android_tls_ptr() = reinterpret_cast<uptr>(thr); 389 if (dead_thread_state == nullptr) { 390 dead_thread_state = reinterpret_cast<ThreadState*>( 391 MmapOrDie(sizeof(ThreadState), "ThreadState")); 392 dead_thread_state->fast_state.SetIgnoreBit(); 393 dead_thread_state->ignore_interceptors = 1; 394 dead_thread_state->is_dead = true; 395 *const_cast<int*>(&dead_thread_state->tid) = -1; 396 CHECK_EQ(0, internal_mprotect(dead_thread_state, sizeof(ThreadState), 397 PROT_READ)); 398 } 399 } 400 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &oldset, nullptr)); 401 } 402 return thr; 403} 404 405void cur_thread_finalize() { 406 __sanitizer_sigset_t emptyset; 407 internal_sigfillset(&emptyset); 408 __sanitizer_sigset_t oldset; 409 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &emptyset, &oldset)); 410 ThreadState* thr = reinterpret_cast<ThreadState*>(*get_android_tls_ptr()); 411 if (thr != dead_thread_state) { 412 *get_android_tls_ptr() = reinterpret_cast<uptr>(dead_thread_state); 413 UnmapOrDie(thr, sizeof(ThreadState)); 414 } 415 CHECK_EQ(0, internal_sigprocmask(SIG_SETMASK, &oldset, nullptr)); 416} 417#endif // SANITIZER_ANDROID 418#endif // if !SANITIZER_GO 419 420} // namespace __tsan 421 422#endif // SANITIZER_LINUX || SANITIZER_FREEBSD || SANITIZER_NETBSD 423