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