1//===-- sanitizer_linux_libcdep.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 shared between AddressSanitizer and ThreadSanitizer 11// run-time libraries and implements linux-specific functions from 12// sanitizer_libc.h. 13//===----------------------------------------------------------------------===// 14 15#include "sanitizer_platform.h" 16 17#if SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_NETBSD || \ 18 SANITIZER_OPENBSD || SANITIZER_SOLARIS 19 20#include "sanitizer_allocator_internal.h" 21#include "sanitizer_atomic.h" 22#include "sanitizer_common.h" 23#include "sanitizer_file.h" 24#include "sanitizer_flags.h" 25#include "sanitizer_freebsd.h" 26#include "sanitizer_getauxval.h" 27#include "sanitizer_linux.h" 28#include "sanitizer_placement_new.h" 29#include "sanitizer_procmaps.h" 30 31#if SANITIZER_NETBSD 32#define _RTLD_SOURCE // Fast LWP private pointer getters in ThreadSelfTlsTcb(). 33#endif 34 35#include <dlfcn.h> // for dlsym() 36#include <link.h> 37#include <pthread.h> 38#include <signal.h> 39#include <sys/resource.h> 40#include <syslog.h> 41 42#if SANITIZER_FREEBSD 43#include <pthread_np.h> 44#include <osreldate.h> 45#include <sys/sysctl.h> 46#define pthread_getattr_np pthread_attr_get_np 47#endif 48 49#if SANITIZER_OPENBSD 50#include <pthread_np.h> 51#include <sys/sysctl.h> 52#endif 53 54#if SANITIZER_NETBSD 55#include <sys/sysctl.h> 56#include <sys/tls.h> 57#endif 58 59#if SANITIZER_SOLARIS 60#include <thread.h> 61#endif 62 63#if SANITIZER_ANDROID 64#include <android/api-level.h> 65#if !defined(CPU_COUNT) && !defined(__aarch64__) 66#include <dirent.h> 67#include <fcntl.h> 68struct __sanitizer::linux_dirent { 69 long d_ino; 70 off_t d_off; 71 unsigned short d_reclen; 72 char d_name[]; 73}; 74#endif 75#endif 76 77#if !SANITIZER_ANDROID 78#include <elf.h> 79#include <unistd.h> 80#endif 81 82namespace __sanitizer { 83 84SANITIZER_WEAK_ATTRIBUTE int 85real_sigaction(int signum, const void *act, void *oldact); 86 87int internal_sigaction(int signum, const void *act, void *oldact) { 88#if !SANITIZER_GO 89 if (&real_sigaction) 90 return real_sigaction(signum, act, oldact); 91#endif 92 return sigaction(signum, (const struct sigaction *)act, 93 (struct sigaction *)oldact); 94} 95 96void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top, 97 uptr *stack_bottom) { 98 CHECK(stack_top); 99 CHECK(stack_bottom); 100 if (at_initialization) { 101 // This is the main thread. Libpthread may not be initialized yet. 102 struct rlimit rl; 103 CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0); 104 105 // Find the mapping that contains a stack variable. 106 MemoryMappingLayout proc_maps(/*cache_enabled*/true); 107 if (proc_maps.Error()) { 108 *stack_top = *stack_bottom = 0; 109 return; 110 } 111 MemoryMappedSegment segment; 112 uptr prev_end = 0; 113 while (proc_maps.Next(&segment)) { 114 if ((uptr)&rl < segment.end) break; 115 prev_end = segment.end; 116 } 117 CHECK((uptr)&rl >= segment.start && (uptr)&rl < segment.end); 118 119 // Get stacksize from rlimit, but clip it so that it does not overlap 120 // with other mappings. 121 uptr stacksize = rl.rlim_cur; 122 if (stacksize > segment.end - prev_end) stacksize = segment.end - prev_end; 123 // When running with unlimited stack size, we still want to set some limit. 124 // The unlimited stack size is caused by 'ulimit -s unlimited'. 125 // Also, for some reason, GNU make spawns subprocesses with unlimited stack. 126 if (stacksize > kMaxThreadStackSize) 127 stacksize = kMaxThreadStackSize; 128 *stack_top = segment.end; 129 *stack_bottom = segment.end - stacksize; 130 return; 131 } 132 uptr stacksize = 0; 133 void *stackaddr = nullptr; 134#if SANITIZER_SOLARIS 135 stack_t ss; 136 CHECK_EQ(thr_stksegment(&ss), 0); 137 stacksize = ss.ss_size; 138 stackaddr = (char *)ss.ss_sp - stacksize; 139#elif SANITIZER_OPENBSD 140 stack_t sattr; 141 CHECK_EQ(pthread_stackseg_np(pthread_self(), &sattr), 0); 142 stackaddr = sattr.ss_sp; 143 stacksize = sattr.ss_size; 144#else // !SANITIZER_SOLARIS 145 pthread_attr_t attr; 146 pthread_attr_init(&attr); 147 CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0); 148 my_pthread_attr_getstack(&attr, &stackaddr, &stacksize); 149 pthread_attr_destroy(&attr); 150#endif // SANITIZER_SOLARIS 151 152 *stack_top = (uptr)stackaddr + stacksize; 153 *stack_bottom = (uptr)stackaddr; 154} 155 156#if !SANITIZER_GO 157bool SetEnv(const char *name, const char *value) { 158 void *f = dlsym(RTLD_NEXT, "setenv"); 159 if (!f) 160 return false; 161 typedef int(*setenv_ft)(const char *name, const char *value, int overwrite); 162 setenv_ft setenv_f; 163 CHECK_EQ(sizeof(setenv_f), sizeof(f)); 164 internal_memcpy(&setenv_f, &f, sizeof(f)); 165 return setenv_f(name, value, 1) == 0; 166} 167#endif 168 169__attribute__((unused)) static bool GetLibcVersion(int *major, int *minor, 170 int *patch) { 171#ifdef _CS_GNU_LIBC_VERSION 172 char buf[64]; 173 uptr len = confstr(_CS_GNU_LIBC_VERSION, buf, sizeof(buf)); 174 if (len >= sizeof(buf)) 175 return false; 176 buf[len] = 0; 177 static const char kGLibC[] = "glibc "; 178 if (internal_strncmp(buf, kGLibC, sizeof(kGLibC) - 1) != 0) 179 return false; 180 const char *p = buf + sizeof(kGLibC) - 1; 181 *major = internal_simple_strtoll(p, &p, 10); 182 *minor = (*p == '.') ? internal_simple_strtoll(p + 1, &p, 10) : 0; 183 *patch = (*p == '.') ? internal_simple_strtoll(p + 1, &p, 10) : 0; 184 return true; 185#else 186 return false; 187#endif 188} 189 190#if !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO && \ 191 !SANITIZER_NETBSD && !SANITIZER_OPENBSD && !SANITIZER_SOLARIS 192static uptr g_tls_size; 193 194#ifdef __i386__ 195# ifndef __GLIBC_PREREQ 196# define CHECK_GET_TLS_STATIC_INFO_VERSION 1 197# else 198# define CHECK_GET_TLS_STATIC_INFO_VERSION (!__GLIBC_PREREQ(2, 27)) 199# endif 200#else 201# define CHECK_GET_TLS_STATIC_INFO_VERSION 0 202#endif 203 204#if CHECK_GET_TLS_STATIC_INFO_VERSION 205# define DL_INTERNAL_FUNCTION __attribute__((regparm(3), stdcall)) 206#else 207# define DL_INTERNAL_FUNCTION 208#endif 209 210namespace { 211struct GetTlsStaticInfoCall { 212 typedef void (*get_tls_func)(size_t*, size_t*); 213}; 214struct GetTlsStaticInfoRegparmCall { 215 typedef void (*get_tls_func)(size_t*, size_t*) DL_INTERNAL_FUNCTION; 216}; 217 218template <typename T> 219void CallGetTls(void* ptr, size_t* size, size_t* align) { 220 typename T::get_tls_func get_tls; 221 CHECK_EQ(sizeof(get_tls), sizeof(ptr)); 222 internal_memcpy(&get_tls, &ptr, sizeof(ptr)); 223 CHECK_NE(get_tls, 0); 224 get_tls(size, align); 225} 226 227bool CmpLibcVersion(int major, int minor, int patch) { 228 int ma; 229 int mi; 230 int pa; 231 if (!GetLibcVersion(&ma, &mi, &pa)) 232 return false; 233 if (ma > major) 234 return true; 235 if (ma < major) 236 return false; 237 if (mi > minor) 238 return true; 239 if (mi < minor) 240 return false; 241 return pa >= patch; 242} 243 244} // namespace 245 246void InitTlsSize() { 247 // all current supported platforms have 16 bytes stack alignment 248 const size_t kStackAlign = 16; 249 void *get_tls_static_info_ptr = dlsym(RTLD_NEXT, "_dl_get_tls_static_info"); 250 size_t tls_size = 0; 251 size_t tls_align = 0; 252 // On i?86, _dl_get_tls_static_info used to be internal_function, i.e. 253 // __attribute__((regparm(3), stdcall)) before glibc 2.27 and is normal 254 // function in 2.27 and later. 255 if (CHECK_GET_TLS_STATIC_INFO_VERSION && !CmpLibcVersion(2, 27, 0)) 256 CallGetTls<GetTlsStaticInfoRegparmCall>(get_tls_static_info_ptr, 257 &tls_size, &tls_align); 258 else 259 CallGetTls<GetTlsStaticInfoCall>(get_tls_static_info_ptr, 260 &tls_size, &tls_align); 261 if (tls_align < kStackAlign) 262 tls_align = kStackAlign; 263 g_tls_size = RoundUpTo(tls_size, tls_align); 264} 265#else 266void InitTlsSize() { } 267#endif // !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO && 268 // !SANITIZER_NETBSD && !SANITIZER_SOLARIS 269 270#if (defined(__x86_64__) || defined(__i386__) || defined(__mips__) || \ 271 defined(__aarch64__) || defined(__powerpc64__) || defined(__s390__) || \ 272 defined(__arm__)) && \ 273 SANITIZER_LINUX && !SANITIZER_ANDROID 274// sizeof(struct pthread) from glibc. 275static atomic_uintptr_t thread_descriptor_size; 276 277uptr ThreadDescriptorSize() { 278 uptr val = atomic_load_relaxed(&thread_descriptor_size); 279 if (val) 280 return val; 281#if defined(__x86_64__) || defined(__i386__) || defined(__arm__) 282 int major; 283 int minor; 284 int patch; 285 if (GetLibcVersion(&major, &minor, &patch) && major == 2) { 286 /* sizeof(struct pthread) values from various glibc versions. */ 287 if (SANITIZER_X32) 288 val = 1728; // Assume only one particular version for x32. 289 // For ARM sizeof(struct pthread) changed in Glibc 2.23. 290 else if (SANITIZER_ARM) 291 val = minor <= 22 ? 1120 : 1216; 292 else if (minor <= 3) 293 val = FIRST_32_SECOND_64(1104, 1696); 294 else if (minor == 4) 295 val = FIRST_32_SECOND_64(1120, 1728); 296 else if (minor == 5) 297 val = FIRST_32_SECOND_64(1136, 1728); 298 else if (minor <= 9) 299 val = FIRST_32_SECOND_64(1136, 1712); 300 else if (minor == 10) 301 val = FIRST_32_SECOND_64(1168, 1776); 302 else if (minor == 11 || (minor == 12 && patch == 1)) 303 val = FIRST_32_SECOND_64(1168, 2288); 304 else if (minor <= 14) 305 val = FIRST_32_SECOND_64(1168, 2304); 306 else 307 val = FIRST_32_SECOND_64(1216, 2304); 308 } 309#elif defined(__mips__) 310 // TODO(sagarthakur): add more values as per different glibc versions. 311 val = FIRST_32_SECOND_64(1152, 1776); 312#elif defined(__aarch64__) 313 // The sizeof (struct pthread) is the same from GLIBC 2.17 to 2.22. 314 val = 1776; 315#elif defined(__powerpc64__) 316 val = 1776; // from glibc.ppc64le 2.20-8.fc21 317#elif defined(__s390__) 318 val = FIRST_32_SECOND_64(1152, 1776); // valid for glibc 2.22 319#endif 320 if (val) 321 atomic_store_relaxed(&thread_descriptor_size, val); 322 return val; 323} 324 325// The offset at which pointer to self is located in the thread descriptor. 326const uptr kThreadSelfOffset = FIRST_32_SECOND_64(8, 16); 327 328uptr ThreadSelfOffset() { 329 return kThreadSelfOffset; 330} 331 332#if defined(__mips__) || defined(__powerpc64__) 333// TlsPreTcbSize includes size of struct pthread_descr and size of tcb 334// head structure. It lies before the static tls blocks. 335static uptr TlsPreTcbSize() { 336# if defined(__mips__) 337 const uptr kTcbHead = 16; // sizeof (tcbhead_t) 338# elif defined(__powerpc64__) 339 const uptr kTcbHead = 88; // sizeof (tcbhead_t) 340# endif 341 const uptr kTlsAlign = 16; 342 const uptr kTlsPreTcbSize = 343 RoundUpTo(ThreadDescriptorSize() + kTcbHead, kTlsAlign); 344 return kTlsPreTcbSize; 345} 346#endif 347 348uptr ThreadSelf() { 349 uptr descr_addr; 350# if defined(__i386__) 351 asm("mov %%gs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset)); 352# elif defined(__x86_64__) 353 asm("mov %%fs:%c1,%0" : "=r"(descr_addr) : "i"(kThreadSelfOffset)); 354# elif defined(__mips__) 355 // MIPS uses TLS variant I. The thread pointer (in hardware register $29) 356 // points to the end of the TCB + 0x7000. The pthread_descr structure is 357 // immediately in front of the TCB. TlsPreTcbSize() includes the size of the 358 // TCB and the size of pthread_descr. 359 const uptr kTlsTcbOffset = 0x7000; 360 uptr thread_pointer; 361 asm volatile(".set push;\ 362 .set mips64r2;\ 363 rdhwr %0,$29;\ 364 .set pop" : "=r" (thread_pointer)); 365 descr_addr = thread_pointer - kTlsTcbOffset - TlsPreTcbSize(); 366# elif defined(__aarch64__) || defined(__arm__) 367 descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer()) - 368 ThreadDescriptorSize(); 369# elif defined(__s390__) 370 descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer()); 371# elif defined(__powerpc64__) 372 // PPC64LE uses TLS variant I. The thread pointer (in GPR 13) 373 // points to the end of the TCB + 0x7000. The pthread_descr structure is 374 // immediately in front of the TCB. TlsPreTcbSize() includes the size of the 375 // TCB and the size of pthread_descr. 376 const uptr kTlsTcbOffset = 0x7000; 377 uptr thread_pointer; 378 asm("addi %0,13,%1" : "=r"(thread_pointer) : "I"(-kTlsTcbOffset)); 379 descr_addr = thread_pointer - TlsPreTcbSize(); 380# else 381# error "unsupported CPU arch" 382# endif 383 return descr_addr; 384} 385#endif // (x86_64 || i386 || MIPS) && SANITIZER_LINUX 386 387#if SANITIZER_FREEBSD 388static void **ThreadSelfSegbase() { 389 void **segbase = 0; 390# if defined(__i386__) 391 // sysarch(I386_GET_GSBASE, segbase); 392 __asm __volatile("mov %%gs:0, %0" : "=r" (segbase)); 393# elif defined(__x86_64__) 394 // sysarch(AMD64_GET_FSBASE, segbase); 395 __asm __volatile("movq %%fs:0, %0" : "=r" (segbase)); 396# else 397# error "unsupported CPU arch" 398# endif 399 return segbase; 400} 401 402uptr ThreadSelf() { 403 return (uptr)ThreadSelfSegbase()[2]; 404} 405#endif // SANITIZER_FREEBSD 406 407#if SANITIZER_NETBSD 408static struct tls_tcb * ThreadSelfTlsTcb() { 409 struct tls_tcb * tcb; 410# ifdef __HAVE___LWP_GETTCB_FAST 411 tcb = (struct tls_tcb *)__lwp_gettcb_fast(); 412# elif defined(__HAVE___LWP_GETPRIVATE_FAST) 413 tcb = (struct tls_tcb *)__lwp_getprivate_fast(); 414# endif 415 return tcb; 416} 417 418uptr ThreadSelf() { 419 return (uptr)ThreadSelfTlsTcb()->tcb_pthread; 420} 421 422int GetSizeFromHdr(struct dl_phdr_info *info, size_t size, void *data) { 423 const Elf_Phdr *hdr = info->dlpi_phdr; 424 const Elf_Phdr *last_hdr = hdr + info->dlpi_phnum; 425 426 for (; hdr != last_hdr; ++hdr) { 427 if (hdr->p_type == PT_TLS && info->dlpi_tls_modid == 1) { 428 *(uptr*)data = hdr->p_memsz; 429 break; 430 } 431 } 432 return 0; 433} 434#endif // SANITIZER_NETBSD 435 436#if !SANITIZER_GO 437static void GetTls(uptr *addr, uptr *size) { 438#if SANITIZER_LINUX && !SANITIZER_ANDROID 439# if defined(__x86_64__) || defined(__i386__) || defined(__s390__) 440 *addr = ThreadSelf(); 441 *size = GetTlsSize(); 442 *addr -= *size; 443 *addr += ThreadDescriptorSize(); 444# elif defined(__mips__) || defined(__aarch64__) || defined(__powerpc64__) \ 445 || defined(__arm__) 446 *addr = ThreadSelf(); 447 *size = GetTlsSize(); 448# else 449 *addr = 0; 450 *size = 0; 451# endif 452#elif SANITIZER_FREEBSD 453 void** segbase = ThreadSelfSegbase(); 454 *addr = 0; 455 *size = 0; 456 if (segbase != 0) { 457 // tcbalign = 16 458 // tls_size = round(tls_static_space, tcbalign); 459 // dtv = segbase[1]; 460 // dtv[2] = segbase - tls_static_space; 461 void **dtv = (void**) segbase[1]; 462 *addr = (uptr) dtv[2]; 463 *size = (*addr == 0) ? 0 : ((uptr) segbase[0] - (uptr) dtv[2]); 464 } 465#elif SANITIZER_NETBSD 466 struct tls_tcb * const tcb = ThreadSelfTlsTcb(); 467 *addr = 0; 468 *size = 0; 469 if (tcb != 0) { 470 // Find size (p_memsz) of dlpi_tls_modid 1 (TLS block of the main program). 471 // ld.elf_so hardcodes the index 1. 472 dl_iterate_phdr(GetSizeFromHdr, size); 473 474 if (*size != 0) { 475 // The block has been found and tcb_dtv[1] contains the base address 476 *addr = (uptr)tcb->tcb_dtv[1]; 477 } 478 } 479#elif SANITIZER_OPENBSD 480 *addr = 0; 481 *size = 0; 482#elif SANITIZER_ANDROID 483 *addr = 0; 484 *size = 0; 485#elif SANITIZER_SOLARIS 486 // FIXME 487 *addr = 0; 488 *size = 0; 489#else 490# error "Unknown OS" 491#endif 492} 493#endif 494 495#if !SANITIZER_GO 496uptr GetTlsSize() { 497#if SANITIZER_FREEBSD || SANITIZER_ANDROID || SANITIZER_NETBSD || \ 498 SANITIZER_OPENBSD || SANITIZER_SOLARIS 499 uptr addr, size; 500 GetTls(&addr, &size); 501 return size; 502#elif defined(__mips__) || defined(__powerpc64__) 503 return RoundUpTo(g_tls_size + TlsPreTcbSize(), 16); 504#else 505 return g_tls_size; 506#endif 507} 508#endif 509 510void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size, 511 uptr *tls_addr, uptr *tls_size) { 512#if SANITIZER_GO 513 // Stub implementation for Go. 514 *stk_addr = *stk_size = *tls_addr = *tls_size = 0; 515#else 516 GetTls(tls_addr, tls_size); 517 518 uptr stack_top, stack_bottom; 519 GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom); 520 *stk_addr = stack_bottom; 521 *stk_size = stack_top - stack_bottom; 522 523 if (!main) { 524 // If stack and tls intersect, make them non-intersecting. 525 if (*tls_addr > *stk_addr && *tls_addr < *stk_addr + *stk_size) { 526 CHECK_GT(*tls_addr + *tls_size, *stk_addr); 527 CHECK_LE(*tls_addr + *tls_size, *stk_addr + *stk_size); 528 *stk_size -= *tls_size; 529 *tls_addr = *stk_addr + *stk_size; 530 } 531 } 532#endif 533} 534 535#if !SANITIZER_FREEBSD && !SANITIZER_OPENBSD 536typedef ElfW(Phdr) Elf_Phdr; 537#elif SANITIZER_WORDSIZE == 32 && __FreeBSD_version <= 902001 // v9.2 538#define Elf_Phdr XElf32_Phdr 539#define dl_phdr_info xdl_phdr_info 540#define dl_iterate_phdr(c, b) xdl_iterate_phdr((c), (b)) 541#endif // !SANITIZER_FREEBSD && !SANITIZER_OPENBSD 542 543struct DlIteratePhdrData { 544 InternalMmapVectorNoCtor<LoadedModule> *modules; 545 bool first; 546}; 547 548static int dl_iterate_phdr_cb(dl_phdr_info *info, size_t size, void *arg) { 549 DlIteratePhdrData *data = (DlIteratePhdrData*)arg; 550 InternalScopedString module_name(kMaxPathLength); 551 if (data->first) { 552 data->first = false; 553 // First module is the binary itself. 554 ReadBinaryNameCached(module_name.data(), module_name.size()); 555 } else if (info->dlpi_name) { 556 module_name.append("%s", info->dlpi_name); 557 } 558 if (module_name[0] == '\0') 559 return 0; 560 LoadedModule cur_module; 561 cur_module.set(module_name.data(), info->dlpi_addr); 562 for (int i = 0; i < (int)info->dlpi_phnum; i++) { 563 const Elf_Phdr *phdr = &info->dlpi_phdr[i]; 564 if (phdr->p_type == PT_LOAD) { 565 uptr cur_beg = info->dlpi_addr + phdr->p_vaddr; 566 uptr cur_end = cur_beg + phdr->p_memsz; 567 bool executable = phdr->p_flags & PF_X; 568 bool writable = phdr->p_flags & PF_W; 569 cur_module.addAddressRange(cur_beg, cur_end, executable, 570 writable); 571 } 572 } 573 data->modules->push_back(cur_module); 574 return 0; 575} 576 577#if SANITIZER_ANDROID && __ANDROID_API__ < 21 578extern "C" __attribute__((weak)) int dl_iterate_phdr( 579 int (*)(struct dl_phdr_info *, size_t, void *), void *); 580#endif 581 582static bool requiresProcmaps() { 583#if SANITIZER_ANDROID && __ANDROID_API__ <= 22 584 // Fall back to /proc/maps if dl_iterate_phdr is unavailable or broken. 585 // The runtime check allows the same library to work with 586 // both K and L (and future) Android releases. 587 return AndroidGetApiLevel() <= ANDROID_LOLLIPOP_MR1; 588#else 589 return false; 590#endif 591} 592 593static void procmapsInit(InternalMmapVectorNoCtor<LoadedModule> *modules) { 594 MemoryMappingLayout memory_mapping(/*cache_enabled*/true); 595 memory_mapping.DumpListOfModules(modules); 596} 597 598void ListOfModules::init() { 599 clearOrInit(); 600 if (requiresProcmaps()) { 601 procmapsInit(&modules_); 602 } else { 603 DlIteratePhdrData data = {&modules_, true}; 604 dl_iterate_phdr(dl_iterate_phdr_cb, &data); 605 } 606} 607 608// When a custom loader is used, dl_iterate_phdr may not contain the full 609// list of modules. Allow callers to fall back to using procmaps. 610void ListOfModules::fallbackInit() { 611 if (!requiresProcmaps()) { 612 clearOrInit(); 613 procmapsInit(&modules_); 614 } else { 615 clear(); 616 } 617} 618 619// getrusage does not give us the current RSS, only the max RSS. 620// Still, this is better than nothing if /proc/self/statm is not available 621// for some reason, e.g. due to a sandbox. 622static uptr GetRSSFromGetrusage() { 623 struct rusage usage; 624 if (getrusage(RUSAGE_SELF, &usage)) // Failed, probably due to a sandbox. 625 return 0; 626 return usage.ru_maxrss << 10; // ru_maxrss is in Kb. 627} 628 629uptr GetRSS() { 630 if (!common_flags()->can_use_proc_maps_statm) 631 return GetRSSFromGetrusage(); 632 fd_t fd = OpenFile("/proc/self/statm", RdOnly); 633 if (fd == kInvalidFd) 634 return GetRSSFromGetrusage(); 635 char buf[64]; 636 uptr len = internal_read(fd, buf, sizeof(buf) - 1); 637 internal_close(fd); 638 if ((sptr)len <= 0) 639 return 0; 640 buf[len] = 0; 641 // The format of the file is: 642 // 1084 89 69 11 0 79 0 643 // We need the second number which is RSS in pages. 644 char *pos = buf; 645 // Skip the first number. 646 while (*pos >= '0' && *pos <= '9') 647 pos++; 648 // Skip whitespaces. 649 while (!(*pos >= '0' && *pos <= '9') && *pos != 0) 650 pos++; 651 // Read the number. 652 uptr rss = 0; 653 while (*pos >= '0' && *pos <= '9') 654 rss = rss * 10 + *pos++ - '0'; 655 return rss * GetPageSizeCached(); 656} 657 658// sysconf(_SC_NPROCESSORS_{CONF,ONLN}) cannot be used on most platforms as 659// they allocate memory. 660u32 GetNumberOfCPUs() { 661#if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_OPENBSD 662 u32 ncpu; 663 int req[2]; 664 uptr len = sizeof(ncpu); 665 req[0] = CTL_HW; 666 req[1] = HW_NCPU; 667 CHECK_EQ(internal_sysctl(req, 2, &ncpu, &len, NULL, 0), 0); 668 return ncpu; 669#elif SANITIZER_ANDROID && !defined(CPU_COUNT) && !defined(__aarch64__) 670 // Fall back to /sys/devices/system/cpu on Android when cpu_set_t doesn't 671 // exist in sched.h. That is the case for toolchains generated with older 672 // NDKs. 673 // This code doesn't work on AArch64 because internal_getdents makes use of 674 // the 64bit getdents syscall, but cpu_set_t seems to always exist on AArch64. 675 uptr fd = internal_open("/sys/devices/system/cpu", O_RDONLY | O_DIRECTORY); 676 if (internal_iserror(fd)) 677 return 0; 678 InternalMmapVector<u8> buffer(4096); 679 uptr bytes_read = buffer.size(); 680 uptr n_cpus = 0; 681 u8 *d_type; 682 struct linux_dirent *entry = (struct linux_dirent *)&buffer[bytes_read]; 683 while (true) { 684 if ((u8 *)entry >= &buffer[bytes_read]) { 685 bytes_read = internal_getdents(fd, (struct linux_dirent *)buffer.data(), 686 buffer.size()); 687 if (internal_iserror(bytes_read) || !bytes_read) 688 break; 689 entry = (struct linux_dirent *)buffer.data(); 690 } 691 d_type = (u8 *)entry + entry->d_reclen - 1; 692 if (d_type >= &buffer[bytes_read] || 693 (u8 *)&entry->d_name[3] >= &buffer[bytes_read]) 694 break; 695 if (entry->d_ino != 0 && *d_type == DT_DIR) { 696 if (entry->d_name[0] == 'c' && entry->d_name[1] == 'p' && 697 entry->d_name[2] == 'u' && 698 entry->d_name[3] >= '0' && entry->d_name[3] <= '9') 699 n_cpus++; 700 } 701 entry = (struct linux_dirent *)(((u8 *)entry) + entry->d_reclen); 702 } 703 internal_close(fd); 704 return n_cpus; 705#elif SANITIZER_SOLARIS 706 return sysconf(_SC_NPROCESSORS_ONLN); 707#else 708 cpu_set_t CPUs; 709 CHECK_EQ(sched_getaffinity(0, sizeof(cpu_set_t), &CPUs), 0); 710 return CPU_COUNT(&CPUs); 711#endif 712} 713 714#if SANITIZER_LINUX 715 716# if SANITIZER_ANDROID 717static atomic_uint8_t android_log_initialized; 718 719void AndroidLogInit() { 720 openlog(GetProcessName(), 0, LOG_USER); 721 atomic_store(&android_log_initialized, 1, memory_order_release); 722} 723 724static bool ShouldLogAfterPrintf() { 725 return atomic_load(&android_log_initialized, memory_order_acquire); 726} 727 728extern "C" SANITIZER_WEAK_ATTRIBUTE 729int async_safe_write_log(int pri, const char* tag, const char* msg); 730extern "C" SANITIZER_WEAK_ATTRIBUTE 731int __android_log_write(int prio, const char* tag, const char* msg); 732 733// ANDROID_LOG_INFO is 4, but can't be resolved at runtime. 734#define SANITIZER_ANDROID_LOG_INFO 4 735 736// async_safe_write_log is a new public version of __libc_write_log that is 737// used behind syslog. It is preferable to syslog as it will not do any dynamic 738// memory allocation or formatting. 739// If the function is not available, syslog is preferred for L+ (it was broken 740// pre-L) as __android_log_write triggers a racey behavior with the strncpy 741// interceptor. Fallback to __android_log_write pre-L. 742void WriteOneLineToSyslog(const char *s) { 743 if (&async_safe_write_log) { 744 async_safe_write_log(SANITIZER_ANDROID_LOG_INFO, GetProcessName(), s); 745 } else if (AndroidGetApiLevel() > ANDROID_KITKAT) { 746 syslog(LOG_INFO, "%s", s); 747 } else { 748 CHECK(&__android_log_write); 749 __android_log_write(SANITIZER_ANDROID_LOG_INFO, nullptr, s); 750 } 751} 752 753extern "C" SANITIZER_WEAK_ATTRIBUTE 754void android_set_abort_message(const char *); 755 756void SetAbortMessage(const char *str) { 757 if (&android_set_abort_message) 758 android_set_abort_message(str); 759} 760# else 761void AndroidLogInit() {} 762 763static bool ShouldLogAfterPrintf() { return true; } 764 765void WriteOneLineToSyslog(const char *s) { syslog(LOG_INFO, "%s", s); } 766 767void SetAbortMessage(const char *str) {} 768# endif // SANITIZER_ANDROID 769 770void LogMessageOnPrintf(const char *str) { 771 if (common_flags()->log_to_syslog && ShouldLogAfterPrintf()) 772 WriteToSyslog(str); 773} 774 775#endif // SANITIZER_LINUX 776 777#if SANITIZER_LINUX && !SANITIZER_GO 778// glibc crashes when using clock_gettime from a preinit_array function as the 779// vDSO function pointers haven't been initialized yet. __progname is 780// initialized after the vDSO function pointers, so if it exists, is not null 781// and is not empty, we can use clock_gettime. 782extern "C" SANITIZER_WEAK_ATTRIBUTE char *__progname; 783INLINE bool CanUseVDSO() { 784 // Bionic is safe, it checks for the vDSO function pointers to be initialized. 785 if (SANITIZER_ANDROID) 786 return true; 787 if (&__progname && __progname && *__progname) 788 return true; 789 return false; 790} 791 792// MonotonicNanoTime is a timing function that can leverage the vDSO by calling 793// clock_gettime. real_clock_gettime only exists if clock_gettime is 794// intercepted, so define it weakly and use it if available. 795extern "C" SANITIZER_WEAK_ATTRIBUTE 796int real_clock_gettime(u32 clk_id, void *tp); 797u64 MonotonicNanoTime() { 798 timespec ts; 799 if (CanUseVDSO()) { 800 if (&real_clock_gettime) 801 real_clock_gettime(CLOCK_MONOTONIC, &ts); 802 else 803 clock_gettime(CLOCK_MONOTONIC, &ts); 804 } else { 805 internal_clock_gettime(CLOCK_MONOTONIC, &ts); 806 } 807 return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec; 808} 809#else 810// Non-Linux & Go always use the syscall. 811u64 MonotonicNanoTime() { 812 timespec ts; 813 internal_clock_gettime(CLOCK_MONOTONIC, &ts); 814 return (u64)ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec; 815} 816#endif // SANITIZER_LINUX && !SANITIZER_GO 817 818#if !SANITIZER_OPENBSD 819void ReExec() { 820 const char *pathname = "/proc/self/exe"; 821 822#if SANITIZER_NETBSD 823 static const int name[] = { 824 CTL_KERN, 825 KERN_PROC_ARGS, 826 -1, 827 KERN_PROC_PATHNAME, 828 }; 829 char path[400]; 830 uptr len; 831 832 len = sizeof(path); 833 if (internal_sysctl(name, ARRAY_SIZE(name), path, &len, NULL, 0) != -1) 834 pathname = path; 835#elif SANITIZER_SOLARIS 836 pathname = getexecname(); 837 CHECK_NE(pathname, NULL); 838#elif SANITIZER_USE_GETAUXVAL 839 // Calling execve with /proc/self/exe sets that as $EXEC_ORIGIN. Binaries that 840 // rely on that will fail to load shared libraries. Query AT_EXECFN instead. 841 pathname = reinterpret_cast<const char *>(getauxval(AT_EXECFN)); 842#endif 843 844 uptr rv = internal_execve(pathname, GetArgv(), GetEnviron()); 845 int rverrno; 846 CHECK_EQ(internal_iserror(rv, &rverrno), true); 847 Printf("execve failed, errno %d\n", rverrno); 848 Die(); 849} 850#endif // !SANITIZER_OPENBSD 851 852} // namespace __sanitizer 853 854#endif 855