compiler-rt/lib/msan/msan_interceptors.cpp

   1 //===-- msan_interceptors.cpp ---------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file is a part of MemorySanitizer.
  10 //
  11 // Interceptors for standard library functions.
  12 //
  13 // FIXME: move as many interceptors as possible into
  14 // sanitizer_common/sanitizer_common_interceptors.h
  15 //===----------------------------------------------------------------------===//
  16
  17 #include "interception/interception.h"
  18 #include "msan.h"
  19 #include "msan_chained_origin_depot.h"
  20 #include "msan_origin.h"
  21 #include "msan_poisoning.h"
  22 #include "msan_report.h"
  23 #include "msan_thread.h"
  24 #include "sanitizer_common/sanitizer_allocator.h"
  25 #include "sanitizer_common/sanitizer_allocator_dlsym.h"
  26 #include "sanitizer_common/sanitizer_allocator_interface.h"
  27 #include "sanitizer_common/sanitizer_atomic.h"
  28 #include "sanitizer_common/sanitizer_common.h"
  29 #include "sanitizer_common/sanitizer_errno.h"
  30 #include "sanitizer_common/sanitizer_errno_codes.h"
  31 #include "sanitizer_common/sanitizer_glibc_version.h"
  32 #include "sanitizer_common/sanitizer_libc.h"
  33 #include "sanitizer_common/sanitizer_linux.h"
  34 #include "sanitizer_common/sanitizer_platform_limits_netbsd.h"
  35 #include "sanitizer_common/sanitizer_platform_limits_posix.h"
  36 #include "sanitizer_common/sanitizer_stackdepot.h"
  37 #include "sanitizer_common/sanitizer_tls_get_addr.h"
  38 #include "sanitizer_common/sanitizer_vector.h"
  39
  40 #if SANITIZER_NETBSD
  41 #define fstat __fstat50
  42 #define gettimeofday __gettimeofday50
  43 #define getrusage __getrusage50
  44 #define tzset __tzset50
  45 #endif
  46
  47 #include <stdarg.h>
  48 // ACHTUNG! No other system header includes in this file.
  49 // Ideally, we should get rid of stdarg.h as well.
  50
  51 using namespace __msan;
  52
  53 using __sanitizer::memory_order;
  54 using __sanitizer::atomic_load;
  55 using __sanitizer::atomic_store;
  56 using __sanitizer::atomic_uintptr_t;
  57
  58 DECLARE_REAL(SIZE_T, strlen, const char *s)
  59 DECLARE_REAL(SIZE_T, strnlen, const char *s, SIZE_T maxlen)
  60 DECLARE_REAL(void *, memcpy, void *dest, const void *src, uptr n)
  61 DECLARE_REAL(void *, memset, void *dest, int c, uptr n)
  62
  63 // True if this is a nested interceptor.
  64 static THREADLOCAL int in_interceptor_scope;
  65
  66 void __msan_scoped_disable_interceptor_checks() { ++in_interceptor_scope; }
  67 void __msan_scoped_enable_interceptor_checks() { --in_interceptor_scope; }
  68
  69 struct InterceptorScope {
  70   InterceptorScope() { ++in_interceptor_scope; }
  71   ~InterceptorScope() { --in_interceptor_scope; }
  72 };
  73
  74 bool IsInInterceptorScope() {
  75   return in_interceptor_scope;
  76 }
  77
  78 struct DlsymAlloc : public DlSymAllocator<DlsymAlloc> {
  79   static bool UseImpl() { return !msan_inited; }
  80 };
  81
  82 #define ENSURE_MSAN_INITED() do { \
  83   CHECK(!msan_init_is_running); \
  84   if (!msan_inited) { \
  85     __msan_init(); \
  86   } \
  87 } while (0)
  88
  89 // Check that [x, x+n) range is unpoisoned.
  90 #define CHECK_UNPOISONED_0(x, n)                                  \
  91   do {                                                            \
  92     sptr __offset = __msan_test_shadow(x, n);                     \
  93     if (__msan::IsInSymbolizerOrUnwider())                        \
  94       break;                                                      \
  95     if (__offset >= 0 && __msan::flags()->report_umrs) {          \
  96       GET_CALLER_PC_BP;                                           \
  97       ReportUMRInsideAddressRange(__func__, x, n, __offset);      \
  98       __msan::PrintWarningWithOrigin(                             \
  99           pc, bp, __msan_get_origin((const char *)x + __offset)); \
 100       if (__msan::flags()->halt_on_error) {                       \
 101         Printf("Exiting\n");                                      \
 102         Die();                                                    \
 103       }                                                           \
 104     }                                                             \
 105   } while (0)
 106
 107 // Check that [x, x+n) range is unpoisoned unless we are in a nested
 108 // interceptor.
 109 #define CHECK_UNPOISONED(x, n)                             \
 110   do {                                                     \
 111     if (!IsInInterceptorScope()) CHECK_UNPOISONED_0(x, n); \
 112   } while (0)
 113
 114 #define CHECK_UNPOISONED_STRING_OF_LEN(x, len, n)               \
 115   CHECK_UNPOISONED((x),                                         \
 116     common_flags()->strict_string_checks ? (len) + 1 : (n) )
 117
 118 #define CHECK_UNPOISONED_STRING(x, n)                           \
 119     CHECK_UNPOISONED_STRING_OF_LEN((x), internal_strlen(x), (n))
 120
 121 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 122 INTERCEPTOR(SIZE_T, fread_unlocked, void *ptr, SIZE_T size, SIZE_T nmemb,
 123             void *file) {
 124   ENSURE_MSAN_INITED();
 125   SIZE_T res = REAL(fread_unlocked)(ptr, size, nmemb, file);
 126   if (res > 0)
 127     __msan_unpoison(ptr, res *size);
 128   return res;
 129 }
 130 #define MSAN_MAYBE_INTERCEPT_FREAD_UNLOCKED INTERCEPT_FUNCTION(fread_unlocked)
 131 #else
 132 #define MSAN_MAYBE_INTERCEPT_FREAD_UNLOCKED
 133 #endif
 134
 135 #if !SANITIZER_NETBSD
 136 INTERCEPTOR(void *, mempcpy, void *dest, const void *src, SIZE_T n) {
 137   return (char *)__msan_memcpy(dest, src, n) + n;
 138 }
 139 #define MSAN_MAYBE_INTERCEPT_MEMPCPY INTERCEPT_FUNCTION(mempcpy)
 140 #else
 141 #define MSAN_MAYBE_INTERCEPT_MEMPCPY
 142 #endif
 143
 144 INTERCEPTOR(void *, memccpy, void *dest, const void *src, int c, SIZE_T n) {
 145   ENSURE_MSAN_INITED();
 146   void *res = REAL(memccpy)(dest, src, c, n);
 147   CHECK(!res || (res >= dest && res <= (char *)dest + n));
 148   SIZE_T sz = res ? (char *)res - (char *)dest : n;
 149   CHECK_UNPOISONED(src, sz);
 150   __msan_unpoison(dest, sz);
 151   return res;
 152 }
 153
 154 INTERCEPTOR(void *, bcopy, const void *src, void *dest, SIZE_T n) {
 155   return __msan_memmove(dest, src, n);
 156 }
 157
 158 INTERCEPTOR(int, posix_memalign, void **memptr, SIZE_T alignment, SIZE_T size) {
 159   GET_MALLOC_STACK_TRACE;
 160   CHECK_NE(memptr, 0);
 161   int res = msan_posix_memalign(memptr, alignment, size, &stack);
 162   if (!res)
 163     __msan_unpoison(memptr, sizeof(*memptr));
 164   return res;
 165 }
 166
 167 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 168 INTERCEPTOR(void *, memalign, SIZE_T alignment, SIZE_T size) {
 169   GET_MALLOC_STACK_TRACE;
 170   return msan_memalign(alignment, size, &stack);
 171 }
 172 #define MSAN_MAYBE_INTERCEPT_MEMALIGN INTERCEPT_FUNCTION(memalign)
 173 #else
 174 #define MSAN_MAYBE_INTERCEPT_MEMALIGN
 175 #endif
 176
 177 INTERCEPTOR(void *, aligned_alloc, SIZE_T alignment, SIZE_T size) {
 178   GET_MALLOC_STACK_TRACE;
 179   return msan_aligned_alloc(alignment, size, &stack);
 180 }
 181
 182 #if !SANITIZER_NETBSD
 183 INTERCEPTOR(void *, __libc_memalign, SIZE_T alignment, SIZE_T size) {
 184   GET_MALLOC_STACK_TRACE;
 185   void *ptr = msan_memalign(alignment, size, &stack);
 186   if (ptr)
 187     DTLS_on_libc_memalign(ptr, size);
 188   return ptr;
 189 }
 190 #define MSAN_MAYBE_INTERCEPT___LIBC_MEMALIGN INTERCEPT_FUNCTION(__libc_memalign)
 191 #else
 192 #define MSAN_MAYBE_INTERCEPT___LIBC_MEMALIGN
 193 #endif
 194
 195 INTERCEPTOR(void *, valloc, SIZE_T size) {
 196   GET_MALLOC_STACK_TRACE;
 197   return msan_valloc(size, &stack);
 198 }
 199
 200 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 201 INTERCEPTOR(void *, pvalloc, SIZE_T size) {
 202   GET_MALLOC_STACK_TRACE;
 203   return msan_pvalloc(size, &stack);
 204 }
 205 #define MSAN_MAYBE_INTERCEPT_PVALLOC INTERCEPT_FUNCTION(pvalloc)
 206 #else
 207 #define MSAN_MAYBE_INTERCEPT_PVALLOC
 208 #endif
 209
 210 INTERCEPTOR(void, free, void *ptr) {
 211   if (UNLIKELY(!ptr))
 212     return;
 213   if (DlsymAlloc::PointerIsMine(ptr))
 214     return DlsymAlloc::Free(ptr);
 215   GET_MALLOC_STACK_TRACE;
 216   MsanDeallocate(&stack, ptr);
 217 }
 218
 219 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 220 INTERCEPTOR(void, cfree, void *ptr) {
 221   if (UNLIKELY(!ptr))
 222     return;
 223   if (DlsymAlloc::PointerIsMine(ptr))
 224     return DlsymAlloc::Free(ptr);
 225   GET_MALLOC_STACK_TRACE;
 226   MsanDeallocate(&stack, ptr);
 227 }
 228 #  define MSAN_MAYBE_INTERCEPT_CFREE INTERCEPT_FUNCTION(cfree)
 229 #else
 230 #define MSAN_MAYBE_INTERCEPT_CFREE
 231 #endif
 232
 233 #if !SANITIZER_NETBSD
 234 INTERCEPTOR(uptr, malloc_usable_size, void *ptr) {
 235   return __sanitizer_get_allocated_size(ptr);
 236 }
 237 #define MSAN_MAYBE_INTERCEPT_MALLOC_USABLE_SIZE \
 238   INTERCEPT_FUNCTION(malloc_usable_size)
 239 #else
 240 #define MSAN_MAYBE_INTERCEPT_MALLOC_USABLE_SIZE
 241 #endif
 242
 243 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 244 // This function actually returns a struct by value, but we can't unpoison a
 245 // temporary! The following is equivalent on all supported platforms but
 246 // aarch64 (which uses a different register for sret value).  We have a test
 247 // to confirm that.
 248 INTERCEPTOR(void, mallinfo, __sanitizer_struct_mallinfo *sret) {
 249 #ifdef __aarch64__
 250   uptr r8;
 251   asm volatile("mov %0,x8" : "=r" (r8));
 252   sret = reinterpret_cast<__sanitizer_struct_mallinfo*>(r8);
 253 #endif
 254   REAL(memset)(sret, 0, sizeof(*sret));
 255   __msan_unpoison(sret, sizeof(*sret));
 256 }
 257 #define MSAN_MAYBE_INTERCEPT_MALLINFO INTERCEPT_FUNCTION(mallinfo)
 258 #else
 259 #define MSAN_MAYBE_INTERCEPT_MALLINFO
 260 #endif
 261
 262 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 263 INTERCEPTOR(int, mallopt, int cmd, int value) {
 264   return 0;
 265 }
 266 #define MSAN_MAYBE_INTERCEPT_MALLOPT INTERCEPT_FUNCTION(mallopt)
 267 #else
 268 #define MSAN_MAYBE_INTERCEPT_MALLOPT
 269 #endif
 270
 271 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 272 INTERCEPTOR(void, malloc_stats, void) {
 273   // FIXME: implement, but don't call REAL(malloc_stats)!
 274 }
 275 #define MSAN_MAYBE_INTERCEPT_MALLOC_STATS INTERCEPT_FUNCTION(malloc_stats)
 276 #else
 277 #define MSAN_MAYBE_INTERCEPT_MALLOC_STATS
 278 #endif
 279
 280 INTERCEPTOR(char *, strcpy, char *dest, const char *src) {
 281   ENSURE_MSAN_INITED();
 282   GET_STORE_STACK_TRACE;
 283   SIZE_T n = internal_strlen(src);
 284   CHECK_UNPOISONED_STRING(src + n, 0);
 285   char *res = REAL(strcpy)(dest, src);
 286   CopyShadowAndOrigin(dest, src, n + 1, &stack);
 287   return res;
 288 }
 289
 290 INTERCEPTOR(char *, strncpy, char *dest, const char *src, SIZE_T n) {
 291   ENSURE_MSAN_INITED();
 292   GET_STORE_STACK_TRACE;
 293   SIZE_T copy_size = internal_strnlen(src, n);
 294   if (copy_size < n)
 295     copy_size++;  // trailing \0
 296   char *res = REAL(strncpy)(dest, src, n);
 297   CopyShadowAndOrigin(dest, src, copy_size, &stack);
 298   __msan_unpoison(dest + copy_size, n - copy_size);
 299   return res;
 300 }
 301
 302 #if !SANITIZER_NETBSD
 303 INTERCEPTOR(char *, stpcpy, char *dest, const char *src) {
 304   ENSURE_MSAN_INITED();
 305   GET_STORE_STACK_TRACE;
 306   SIZE_T n = internal_strlen(src);
 307   CHECK_UNPOISONED_STRING(src + n, 0);
 308   char *res = REAL(stpcpy)(dest, src);
 309   CopyShadowAndOrigin(dest, src, n + 1, &stack);
 310   return res;
 311 }
 312
 313 INTERCEPTOR(char *, stpncpy, char *dest, const char *src, SIZE_T n) {
 314   ENSURE_MSAN_INITED();
 315   GET_STORE_STACK_TRACE;
 316   SIZE_T copy_size = Min(n, internal_strnlen(src, n) + 1);
 317   char *res = REAL(stpncpy)(dest, src, n);
 318   CopyShadowAndOrigin(dest, src, copy_size, &stack);
 319   __msan_unpoison(dest + copy_size, n - copy_size);
 320   return res;
 321 }
 322 #  define MSAN_MAYBE_INTERCEPT_STPCPY INTERCEPT_FUNCTION(stpcpy)
 323 #  define MSAN_MAYBE_INTERCEPT_STPNCPY INTERCEPT_FUNCTION(stpncpy)
 324 #else
 325 #define MSAN_MAYBE_INTERCEPT_STPCPY
 326 #  define MSAN_MAYBE_INTERCEPT_STPNCPY
 327 #endif
 328
 329 INTERCEPTOR(char *, strdup, char *src) {
 330   ENSURE_MSAN_INITED();
 331   GET_STORE_STACK_TRACE;
 332   // On FreeBSD strdup() leverages strlen().
 333   InterceptorScope interceptor_scope;
 334   SIZE_T n = internal_strlen(src);
 335   CHECK_UNPOISONED_STRING(src + n, 0);
 336   char *res = REAL(strdup)(src);
 337   CopyShadowAndOrigin(res, src, n + 1, &stack);
 338   return res;
 339 }
 340
 341 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 342 INTERCEPTOR(char *, __strdup, char *src) {
 343   ENSURE_MSAN_INITED();
 344   GET_STORE_STACK_TRACE;
 345   SIZE_T n = internal_strlen(src);
 346   CHECK_UNPOISONED_STRING(src + n, 0);
 347   char *res = REAL(__strdup)(src);
 348   CopyShadowAndOrigin(res, src, n + 1, &stack);
 349   return res;
 350 }
 351 #define MSAN_MAYBE_INTERCEPT___STRDUP INTERCEPT_FUNCTION(__strdup)
 352 #else
 353 #define MSAN_MAYBE_INTERCEPT___STRDUP
 354 #endif
 355
 356 #if !SANITIZER_NETBSD
 357 INTERCEPTOR(char *, gcvt, double number, SIZE_T ndigit, char *buf) {
 358   ENSURE_MSAN_INITED();
 359   char *res = REAL(gcvt)(number, ndigit, buf);
 360   SIZE_T n = internal_strlen(buf);
 361   __msan_unpoison(buf, n + 1);
 362   return res;
 363 }
 364 #define MSAN_MAYBE_INTERCEPT_GCVT INTERCEPT_FUNCTION(gcvt)
 365 #else
 366 #define MSAN_MAYBE_INTERCEPT_GCVT
 367 #endif
 368
 369 INTERCEPTOR(char *, strcat, char *dest, const char *src) {
 370   ENSURE_MSAN_INITED();
 371   GET_STORE_STACK_TRACE;
 372   SIZE_T src_size = internal_strlen(src);
 373   SIZE_T dest_size = internal_strlen(dest);
 374   CHECK_UNPOISONED_STRING(src + src_size, 0);
 375   CHECK_UNPOISONED_STRING(dest + dest_size, 0);
 376   char *res = REAL(strcat)(dest, src);
 377   CopyShadowAndOrigin(dest + dest_size, src, src_size + 1, &stack);
 378   return res;
 379 }
 380
 381 INTERCEPTOR(char *, strncat, char *dest, const char *src, SIZE_T n) {
 382   ENSURE_MSAN_INITED();
 383   GET_STORE_STACK_TRACE;
 384   SIZE_T dest_size = internal_strlen(dest);
 385   SIZE_T copy_size = internal_strnlen(src, n);
 386   CHECK_UNPOISONED_STRING(dest + dest_size, 0);
 387   char *res = REAL(strncat)(dest, src, n);
 388   CopyShadowAndOrigin(dest + dest_size, src, copy_size, &stack);
 389   __msan_unpoison(dest + dest_size + copy_size, 1); // \0
 390   return res;
 391 }
 392
 393 // Hack: always pass nptr and endptr as part of __VA_ARGS_ to avoid having to
 394 // deal with empty __VA_ARGS__ in the case of INTERCEPTOR_STRTO.
 395 #define INTERCEPTOR_STRTO_BODY(ret_type, func, ...) \
 396   ENSURE_MSAN_INITED();                             \
 397   ret_type res = REAL(func)(__VA_ARGS__);           \
 398   __msan_unpoison(endptr, sizeof(*endptr));         \
 399   return res;
 400
 401 #define INTERCEPTOR_STRTO(ret_type, func, char_type)                       \
 402   INTERCEPTOR(ret_type, func, const char_type *nptr, char_type **endptr) { \
 403     INTERCEPTOR_STRTO_BODY(ret_type, func, nptr, endptr);                  \
 404   }
 405
 406 #define INTERCEPTOR_STRTO_BASE(ret_type, func, char_type)                \
 407   INTERCEPTOR(ret_type, func, const char_type *nptr, char_type **endptr, \
 408               int base) {                                                \
 409     INTERCEPTOR_STRTO_BODY(ret_type, func, nptr, endptr, base);          \
 410   }
 411
 412 #define INTERCEPTOR_STRTO_LOC(ret_type, func, char_type)                 \
 413   INTERCEPTOR(ret_type, func, const char_type *nptr, char_type **endptr, \
 414               void *loc) {                                               \
 415     INTERCEPTOR_STRTO_BODY(ret_type, func, nptr, endptr, loc);           \
 416   }
 417
 418 #define INTERCEPTOR_STRTO_BASE_LOC(ret_type, func, char_type)            \
 419   INTERCEPTOR(ret_type, func, const char_type *nptr, char_type **endptr, \
 420               int base, void *loc) {                                     \
 421     INTERCEPTOR_STRTO_BODY(ret_type, func, nptr, endptr, base, loc);     \
 422   }
 423
 424 #if SANITIZER_NETBSD
 425 #define INTERCEPTORS_STRTO(ret_type, func, char_type)      \
 426   INTERCEPTOR_STRTO(ret_type, func, char_type)             \
 427   INTERCEPTOR_STRTO_LOC(ret_type, func##_l, char_type)
 428
 429 #define INTERCEPTORS_STRTO_BASE(ret_type, func, char_type)      \
 430   INTERCEPTOR_STRTO_BASE(ret_type, func, char_type)             \
 431   INTERCEPTOR_STRTO_BASE_LOC(ret_type, func##_l, char_type)
 432
 433 #else
 434 #define INTERCEPTORS_STRTO(ret_type, func, char_type)      \
 435   INTERCEPTOR_STRTO(ret_type, func, char_type)             \
 436   INTERCEPTOR_STRTO_LOC(ret_type, func##_l, char_type)     \
 437   INTERCEPTOR_STRTO_LOC(ret_type, __##func##_l, char_type) \
 438   INTERCEPTOR_STRTO_LOC(ret_type, __##func##_internal, char_type)
 439
 440 #define INTERCEPTORS_STRTO_BASE(ret_type, func, char_type)      \
 441   INTERCEPTOR_STRTO_BASE(ret_type, func, char_type)             \
 442   INTERCEPTOR_STRTO_BASE_LOC(ret_type, func##_l, char_type)     \
 443   INTERCEPTOR_STRTO_BASE_LOC(ret_type, __##func##_l, char_type) \
 444   INTERCEPTOR_STRTO_BASE_LOC(ret_type, __##func##_internal, char_type)
 445 #endif
 446
 447 INTERCEPTORS_STRTO(double, strtod, char)
 448 INTERCEPTORS_STRTO(float, strtof, char)
 449 INTERCEPTORS_STRTO(long double, strtold, char)
 450 INTERCEPTORS_STRTO_BASE(long, strtol, char)
 451 INTERCEPTORS_STRTO_BASE(long long, strtoll, char)
 452 INTERCEPTORS_STRTO_BASE(unsigned long, strtoul, char)
 453 INTERCEPTORS_STRTO_BASE(unsigned long long, strtoull, char)
 454 INTERCEPTORS_STRTO_BASE(u64, strtouq, char)
 455
 456 INTERCEPTORS_STRTO(double, wcstod, wchar_t)
 457 INTERCEPTORS_STRTO(float, wcstof, wchar_t)
 458 INTERCEPTORS_STRTO(long double, wcstold, wchar_t)
 459 INTERCEPTORS_STRTO_BASE(long, wcstol, wchar_t)
 460 INTERCEPTORS_STRTO_BASE(long long, wcstoll, wchar_t)
 461 INTERCEPTORS_STRTO_BASE(unsigned long, wcstoul, wchar_t)
 462 INTERCEPTORS_STRTO_BASE(unsigned long long, wcstoull, wchar_t)
 463
 464 #if SANITIZER_NETBSD
 465 #define INTERCEPT_STRTO(func) \
 466   INTERCEPT_FUNCTION(func); \
 467   INTERCEPT_FUNCTION(func##_l);
 468 #else
 469 #define INTERCEPT_STRTO(func) \
 470   INTERCEPT_FUNCTION(func); \
 471   INTERCEPT_FUNCTION(func##_l); \
 472   INTERCEPT_FUNCTION(__##func##_l); \
 473   INTERCEPT_FUNCTION(__##func##_internal);
 474 #endif
 475
 476
 477 // FIXME: support *wprintf in common format interceptors.
 478 INTERCEPTOR(int, vswprintf, void *str, uptr size, void *format, va_list ap) {
 479   ENSURE_MSAN_INITED();
 480   int res = REAL(vswprintf)(str, size, format, ap);
 481   if (res >= 0) {
 482     __msan_unpoison(str, 4 * (res + 1));
 483   }
 484   return res;
 485 }
 486
 487 INTERCEPTOR(int, swprintf, void *str, uptr size, void *format, ...) {
 488   ENSURE_MSAN_INITED();
 489   va_list ap;
 490   va_start(ap, format);
 491   int res = vswprintf(str, size, format, ap);
 492   va_end(ap);
 493   return res;
 494 }
 495
 496 #define INTERCEPTOR_STRFTIME_BODY(char_type, ret_type, func, s, ...) \
 497   ENSURE_MSAN_INITED();                                              \
 498   InterceptorScope interceptor_scope;                                \
 499   ret_type res = REAL(func)(s, __VA_ARGS__);                         \
 500   if (s) __msan_unpoison(s, sizeof(char_type) * (res + 1));          \
 501   return res;
 502
 503 INTERCEPTOR(SIZE_T, strftime, char *s, SIZE_T max, const char *format,
 504             __sanitizer_tm *tm) {
 505   INTERCEPTOR_STRFTIME_BODY(char, SIZE_T, strftime, s, max, format, tm);
 506 }
 507
 508 INTERCEPTOR(SIZE_T, strftime_l, char *s, SIZE_T max, const char *format,
 509             __sanitizer_tm *tm, void *loc) {
 510   INTERCEPTOR_STRFTIME_BODY(char, SIZE_T, strftime_l, s, max, format, tm, loc);
 511 }
 512
 513 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 514 INTERCEPTOR(SIZE_T, __strftime_l, char *s, SIZE_T max, const char *format,
 515             __sanitizer_tm *tm, void *loc) {
 516   INTERCEPTOR_STRFTIME_BODY(char, SIZE_T, __strftime_l, s, max, format, tm,
 517                             loc);
 518 }
 519 #define MSAN_MAYBE_INTERCEPT___STRFTIME_L INTERCEPT_FUNCTION(__strftime_l)
 520 #else
 521 #define MSAN_MAYBE_INTERCEPT___STRFTIME_L
 522 #endif
 523
 524 INTERCEPTOR(SIZE_T, wcsftime, wchar_t *s, SIZE_T max, const wchar_t *format,
 525             __sanitizer_tm *tm) {
 526   INTERCEPTOR_STRFTIME_BODY(wchar_t, SIZE_T, wcsftime, s, max, format, tm);
 527 }
 528
 529 INTERCEPTOR(SIZE_T, wcsftime_l, wchar_t *s, SIZE_T max, const wchar_t *format,
 530             __sanitizer_tm *tm, void *loc) {
 531   INTERCEPTOR_STRFTIME_BODY(wchar_t, SIZE_T, wcsftime_l, s, max, format, tm,
 532                             loc);
 533 }
 534
 535 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 536 INTERCEPTOR(SIZE_T, __wcsftime_l, wchar_t *s, SIZE_T max, const wchar_t *format,
 537             __sanitizer_tm *tm, void *loc) {
 538   INTERCEPTOR_STRFTIME_BODY(wchar_t, SIZE_T, __wcsftime_l, s, max, format, tm,
 539                             loc);
 540 }
 541 #define MSAN_MAYBE_INTERCEPT___WCSFTIME_L INTERCEPT_FUNCTION(__wcsftime_l)
 542 #else
 543 #define MSAN_MAYBE_INTERCEPT___WCSFTIME_L
 544 #endif
 545
 546 INTERCEPTOR(int, mbtowc, wchar_t *dest, const char *src, SIZE_T n) {
 547   ENSURE_MSAN_INITED();
 548   int res = REAL(mbtowc)(dest, src, n);
 549   if (res != -1 && dest) __msan_unpoison(dest, sizeof(wchar_t));
 550   return res;
 551 }
 552
 553 INTERCEPTOR(SIZE_T, mbrtowc, wchar_t *dest, const char *src, SIZE_T n,
 554             void *ps) {
 555   ENSURE_MSAN_INITED();
 556   SIZE_T res = REAL(mbrtowc)(dest, src, n, ps);
 557   if (res != (SIZE_T)-1 && dest) __msan_unpoison(dest, sizeof(wchar_t));
 558   return res;
 559 }
 560
 561 // wchar_t *wmemcpy(wchar_t *dest, const wchar_t *src, SIZE_T n);
 562 INTERCEPTOR(wchar_t *, wmemcpy, wchar_t *dest, const wchar_t *src, SIZE_T n) {
 563   ENSURE_MSAN_INITED();
 564   GET_STORE_STACK_TRACE;
 565   wchar_t *res = REAL(wmemcpy)(dest, src, n);
 566   CopyShadowAndOrigin(dest, src, n * sizeof(wchar_t), &stack);
 567   return res;
 568 }
 569
 570 #if !SANITIZER_NETBSD
 571 INTERCEPTOR(wchar_t *, wmempcpy, wchar_t *dest, const wchar_t *src, SIZE_T n) {
 572   ENSURE_MSAN_INITED();
 573   GET_STORE_STACK_TRACE;
 574   wchar_t *res = REAL(wmempcpy)(dest, src, n);
 575   CopyShadowAndOrigin(dest, src, n * sizeof(wchar_t), &stack);
 576   return res;
 577 }
 578 #define MSAN_MAYBE_INTERCEPT_WMEMPCPY INTERCEPT_FUNCTION(wmempcpy)
 579 #else
 580 #define MSAN_MAYBE_INTERCEPT_WMEMPCPY
 581 #endif
 582
 583 INTERCEPTOR(wchar_t *, wmemset, wchar_t *s, wchar_t c, SIZE_T n) {
 584   CHECK(MEM_IS_APP(s));
 585   ENSURE_MSAN_INITED();
 586   wchar_t *res = REAL(wmemset)(s, c, n);
 587   __msan_unpoison(s, n * sizeof(wchar_t));
 588   return res;
 589 }
 590
 591 INTERCEPTOR(wchar_t *, wmemmove, wchar_t *dest, const wchar_t *src, SIZE_T n) {
 592   ENSURE_MSAN_INITED();
 593   GET_STORE_STACK_TRACE;
 594   wchar_t *res = REAL(wmemmove)(dest, src, n);
 595   MoveShadowAndOrigin(dest, src, n * sizeof(wchar_t), &stack);
 596   return res;
 597 }
 598
 599 INTERCEPTOR(int, wcscmp, const wchar_t *s1, const wchar_t *s2) {
 600   ENSURE_MSAN_INITED();
 601   int res = REAL(wcscmp)(s1, s2);
 602   return res;
 603 }
 604
 605 INTERCEPTOR(int, gettimeofday, void *tv, void *tz) {
 606   ENSURE_MSAN_INITED();
 607   int res = REAL(gettimeofday)(tv, tz);
 608   if (tv)
 609     __msan_unpoison(tv, 16);
 610   if (tz)
 611     __msan_unpoison(tz, 8);
 612   return res;
 613 }
 614
 615 #if !SANITIZER_NETBSD
 616 INTERCEPTOR(char *, fcvt, double x, int a, int *b, int *c) {
 617   ENSURE_MSAN_INITED();
 618   char *res = REAL(fcvt)(x, a, b, c);
 619   __msan_unpoison(b, sizeof(*b));
 620   __msan_unpoison(c, sizeof(*c));
 621   if (res)
 622     __msan_unpoison(res, internal_strlen(res) + 1);
 623   return res;
 624 }
 625 #define MSAN_MAYBE_INTERCEPT_FCVT INTERCEPT_FUNCTION(fcvt)
 626 #else
 627 #define MSAN_MAYBE_INTERCEPT_FCVT
 628 #endif
 629
 630 INTERCEPTOR(char *, getenv, char *name) {
 631   if (msan_init_is_running)
 632     return REAL(getenv)(name);
 633   ENSURE_MSAN_INITED();
 634   char *res = REAL(getenv)(name);
 635   if (res)
 636     __msan_unpoison(res, internal_strlen(res) + 1);
 637   return res;
 638 }
 639
 640 extern char **environ;
 641
 642 static void UnpoisonEnviron() {
 643   char **envp = environ;
 644   for (; *envp; ++envp) {
 645     __msan_unpoison(envp, sizeof(*envp));
 646     __msan_unpoison(*envp, internal_strlen(*envp) + 1);
 647   }
 648   // Trailing NULL pointer.
 649   __msan_unpoison(envp, sizeof(*envp));
 650 }
 651
 652 INTERCEPTOR(int, setenv, const char *name, const char *value, int overwrite) {
 653   ENSURE_MSAN_INITED();
 654   CHECK_UNPOISONED_STRING(name, 0);
 655   int res = REAL(setenv)(name, value, overwrite);
 656   if (!res) UnpoisonEnviron();
 657   return res;
 658 }
 659
 660 INTERCEPTOR(int, putenv, char *string) {
 661   ENSURE_MSAN_INITED();
 662   int res = REAL(putenv)(string);
 663   if (!res) UnpoisonEnviron();
 664   return res;
 665 }
 666
 667 #define SANITIZER_STAT_LINUX (SANITIZER_LINUX && __GLIBC_PREREQ(2, 33))
 668 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_STAT_LINUX
 669 INTERCEPTOR(int, fstat, int fd, void *buf) {
 670   ENSURE_MSAN_INITED();
 671   int res = REAL(fstat)(fd, buf);
 672   if (!res)
 673     __msan_unpoison(buf, __sanitizer::struct_stat_sz);
 674   return res;
 675 }
 676 #  define MSAN_MAYBE_INTERCEPT_FSTAT MSAN_INTERCEPT_FUNC(fstat)
 677 #else
 678 #define MSAN_MAYBE_INTERCEPT_FSTAT
 679 #endif
 680
 681 #if SANITIZER_STAT_LINUX
 682 INTERCEPTOR(int, fstat64, int fd, void *buf) {
 683   ENSURE_MSAN_INITED();
 684   int res = REAL(fstat64)(fd, buf);
 685   if (!res)
 686     __msan_unpoison(buf, __sanitizer::struct_stat64_sz);
 687   return res;
 688 }
 689 #  define MSAN_MAYBE_INTERCEPT_FSTAT64 MSAN_INTERCEPT_FUNC(fstat64)
 690 #else
 691 #  define MSAN_MAYBE_INTERCEPT_FSTAT64
 692 #endif
 693
 694 #if SANITIZER_GLIBC
 695 INTERCEPTOR(int, __fxstat, int magic, int fd, void *buf) {
 696   ENSURE_MSAN_INITED();
 697   int res = REAL(__fxstat)(magic, fd, buf);
 698   if (!res)
 699     __msan_unpoison(buf, __sanitizer::struct_stat_sz);
 700   return res;
 701 }
 702 #  define MSAN_MAYBE_INTERCEPT___FXSTAT MSAN_INTERCEPT_FUNC(__fxstat)
 703 #else
 704 #define MSAN_MAYBE_INTERCEPT___FXSTAT
 705 #endif
 706
 707 #if SANITIZER_GLIBC
 708 INTERCEPTOR(int, __fxstat64, int magic, int fd, void *buf) {
 709   ENSURE_MSAN_INITED();
 710   int res = REAL(__fxstat64)(magic, fd, buf);
 711   if (!res)
 712     __msan_unpoison(buf, __sanitizer::struct_stat64_sz);
 713   return res;
 714 }
 715 #  define MSAN_MAYBE_INTERCEPT___FXSTAT64 MSAN_INTERCEPT_FUNC(__fxstat64)
 716 #else
 717 #  define MSAN_MAYBE_INTERCEPT___FXSTAT64
 718 #endif
 719
 720 #if SANITIZER_FREEBSD || SANITIZER_NETBSD || SANITIZER_STAT_LINUX
 721 INTERCEPTOR(int, fstatat, int fd, char *pathname, void *buf, int flags) {
 722   ENSURE_MSAN_INITED();
 723   int res = REAL(fstatat)(fd, pathname, buf, flags);
 724   if (!res) __msan_unpoison(buf, __sanitizer::struct_stat_sz);
 725   return res;
 726 }
 727 #  define MSAN_MAYBE_INTERCEPT_FSTATAT MSAN_INTERCEPT_FUNC(fstatat)
 728 #else
 729 #  define MSAN_MAYBE_INTERCEPT_FSTATAT
 730 #endif
 731
 732 #if SANITIZER_STAT_LINUX
 733 INTERCEPTOR(int, fstatat64, int fd, char *pathname, void *buf, int flags) {
 734   ENSURE_MSAN_INITED();
 735   int res = REAL(fstatat64)(fd, pathname, buf, flags);
 736   if (!res)
 737     __msan_unpoison(buf, __sanitizer::struct_stat64_sz);
 738   return res;
 739 }
 740 #  define MSAN_MAYBE_INTERCEPT_FSTATAT64 MSAN_INTERCEPT_FUNC(fstatat64)
 741 #else
 742 #  define MSAN_MAYBE_INTERCEPT_FSTATAT64
 743 #endif
 744
 745 #if SANITIZER_GLIBC
 746 INTERCEPTOR(int, __fxstatat, int magic, int fd, char *pathname, void *buf,
 747             int flags) {
 748   ENSURE_MSAN_INITED();
 749   int res = REAL(__fxstatat)(magic, fd, pathname, buf, flags);
 750   if (!res) __msan_unpoison(buf, __sanitizer::struct_stat_sz);
 751   return res;
 752 }
 753 #  define MSAN_MAYBE_INTERCEPT___FXSTATAT MSAN_INTERCEPT_FUNC(__fxstatat)
 754 #else
 755 #  define MSAN_MAYBE_INTERCEPT___FXSTATAT
 756 #endif
 757
 758 #if SANITIZER_GLIBC
 759 INTERCEPTOR(int, __fxstatat64, int magic, int fd, char *pathname, void *buf,
 760             int flags) {
 761   ENSURE_MSAN_INITED();
 762   int res = REAL(__fxstatat64)(magic, fd, pathname, buf, flags);
 763   if (!res) __msan_unpoison(buf, __sanitizer::struct_stat64_sz);
 764   return res;
 765 }
 766 #  define MSAN_MAYBE_INTERCEPT___FXSTATAT64 MSAN_INTERCEPT_FUNC(__fxstatat64)
 767 #else
 768 #  define MSAN_MAYBE_INTERCEPT___FXSTATAT64
 769 #endif
 770
 771 INTERCEPTOR(int, pipe, int pipefd[2]) {
 772   if (msan_init_is_running)
 773     return REAL(pipe)(pipefd);
 774   ENSURE_MSAN_INITED();
 775   int res = REAL(pipe)(pipefd);
 776   if (!res)
 777     __msan_unpoison(pipefd, sizeof(int[2]));
 778   return res;
 779 }
 780
 781 INTERCEPTOR(int, pipe2, int pipefd[2], int flags) {
 782   ENSURE_MSAN_INITED();
 783   int res = REAL(pipe2)(pipefd, flags);
 784   if (!res)
 785     __msan_unpoison(pipefd, sizeof(int[2]));
 786   return res;
 787 }
 788
 789 INTERCEPTOR(int, socketpair, int domain, int type, int protocol, int sv[2]) {
 790   ENSURE_MSAN_INITED();
 791   int res = REAL(socketpair)(domain, type, protocol, sv);
 792   if (!res)
 793     __msan_unpoison(sv, sizeof(int[2]));
 794   return res;
 795 }
 796
 797 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 798 INTERCEPTOR(char *, fgets_unlocked, char *s, int size, void *stream) {
 799   ENSURE_MSAN_INITED();
 800   char *res = REAL(fgets_unlocked)(s, size, stream);
 801   if (res)
 802     __msan_unpoison(s, internal_strlen(s) + 1);
 803   return res;
 804 }
 805 #define MSAN_MAYBE_INTERCEPT_FGETS_UNLOCKED INTERCEPT_FUNCTION(fgets_unlocked)
 806 #else
 807 #define MSAN_MAYBE_INTERCEPT_FGETS_UNLOCKED
 808 #endif
 809
 810 #define INTERCEPTOR_GETRLIMIT_BODY(func, resource, rlim)  \
 811   if (msan_init_is_running)                               \
 812     return REAL(getrlimit)(resource, rlim);               \
 813   ENSURE_MSAN_INITED();                                   \
 814   int res = REAL(func)(resource, rlim);                   \
 815   if (!res)                                               \
 816     __msan_unpoison(rlim, __sanitizer::struct_rlimit_sz); \
 817   return res
 818
 819 INTERCEPTOR(int, getrlimit, int resource, void *rlim) {
 820   INTERCEPTOR_GETRLIMIT_BODY(getrlimit, resource, rlim);
 821 }
 822
 823 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 824 INTERCEPTOR(int, __getrlimit, int resource, void *rlim) {
 825   INTERCEPTOR_GETRLIMIT_BODY(__getrlimit, resource, rlim);
 826 }
 827
 828 INTERCEPTOR(int, getrlimit64, int resource, void *rlim) {
 829   if (msan_init_is_running) return REAL(getrlimit64)(resource, rlim);
 830   ENSURE_MSAN_INITED();
 831   int res = REAL(getrlimit64)(resource, rlim);
 832   if (!res) __msan_unpoison(rlim, __sanitizer::struct_rlimit64_sz);
 833   return res;
 834 }
 835
 836 INTERCEPTOR(int, prlimit, int pid, int resource, void *new_rlimit,
 837             void *old_rlimit) {
 838   if (msan_init_is_running)
 839     return REAL(prlimit)(pid, resource, new_rlimit, old_rlimit);
 840   ENSURE_MSAN_INITED();
 841   CHECK_UNPOISONED(new_rlimit, __sanitizer::struct_rlimit_sz);
 842   int res = REAL(prlimit)(pid, resource, new_rlimit, old_rlimit);
 843   if (!res) __msan_unpoison(old_rlimit, __sanitizer::struct_rlimit_sz);
 844   return res;
 845 }
 846
 847 INTERCEPTOR(int, prlimit64, int pid, int resource, void *new_rlimit,
 848             void *old_rlimit) {
 849   if (msan_init_is_running)
 850     return REAL(prlimit64)(pid, resource, new_rlimit, old_rlimit);
 851   ENSURE_MSAN_INITED();
 852   CHECK_UNPOISONED(new_rlimit, __sanitizer::struct_rlimit64_sz);
 853   int res = REAL(prlimit64)(pid, resource, new_rlimit, old_rlimit);
 854   if (!res) __msan_unpoison(old_rlimit, __sanitizer::struct_rlimit64_sz);
 855   return res;
 856 }
 857
 858 #define MSAN_MAYBE_INTERCEPT___GETRLIMIT INTERCEPT_FUNCTION(__getrlimit)
 859 #define MSAN_MAYBE_INTERCEPT_GETRLIMIT64 INTERCEPT_FUNCTION(getrlimit64)
 860 #define MSAN_MAYBE_INTERCEPT_PRLIMIT INTERCEPT_FUNCTION(prlimit)
 861 #define MSAN_MAYBE_INTERCEPT_PRLIMIT64 INTERCEPT_FUNCTION(prlimit64)
 862 #else
 863 #define MSAN_MAYBE_INTERCEPT___GETRLIMIT
 864 #define MSAN_MAYBE_INTERCEPT_GETRLIMIT64
 865 #define MSAN_MAYBE_INTERCEPT_PRLIMIT
 866 #define MSAN_MAYBE_INTERCEPT_PRLIMIT64
 867 #endif
 868
 869 INTERCEPTOR(int, gethostname, char *name, SIZE_T len) {
 870   ENSURE_MSAN_INITED();
 871   int res = REAL(gethostname)(name, len);
 872   if (!res || (res == -1 && errno == errno_ENAMETOOLONG)) {
 873     SIZE_T real_len = internal_strnlen(name, len);
 874     if (real_len < len)
 875       ++real_len;
 876     __msan_unpoison(name, real_len);
 877   }
 878   return res;
 879 }
 880
 881 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 882 INTERCEPTOR(int, epoll_wait, int epfd, void *events, int maxevents,
 883     int timeout) {
 884   ENSURE_MSAN_INITED();
 885   int res = REAL(epoll_wait)(epfd, events, maxevents, timeout);
 886   if (res > 0) {
 887     __msan_unpoison(events, __sanitizer::struct_epoll_event_sz * res);
 888   }
 889   return res;
 890 }
 891 #define MSAN_MAYBE_INTERCEPT_EPOLL_WAIT INTERCEPT_FUNCTION(epoll_wait)
 892 #else
 893 #define MSAN_MAYBE_INTERCEPT_EPOLL_WAIT
 894 #endif
 895
 896 #if !SANITIZER_FREEBSD && !SANITIZER_NETBSD
 897 INTERCEPTOR(int, epoll_pwait, int epfd, void *events, int maxevents,
 898     int timeout, void *sigmask) {
 899   ENSURE_MSAN_INITED();
 900   int res = REAL(epoll_pwait)(epfd, events, maxevents, timeout, sigmask);
 901   if (res > 0) {
 902     __msan_unpoison(events, __sanitizer::struct_epoll_event_sz * res);
 903   }
 904   return res;
 905 }
 906 #define MSAN_MAYBE_INTERCEPT_EPOLL_PWAIT INTERCEPT_FUNCTION(epoll_pwait)
 907 #else
 908 #define MSAN_MAYBE_INTERCEPT_EPOLL_PWAIT
 909 #endif
 910
 911 INTERCEPTOR(void *, calloc, SIZE_T nmemb, SIZE_T size) {
 912   GET_MALLOC_STACK_TRACE;
 913   if (DlsymAlloc::Use())
 914     return DlsymAlloc::Callocate(nmemb, size);
 915   return msan_calloc(nmemb, size, &stack);
 916 }
 917
 918 INTERCEPTOR(void *, realloc, void *ptr, SIZE_T size) {
 919   if (DlsymAlloc::Use() || DlsymAlloc::PointerIsMine(ptr))
 920     return DlsymAlloc::Realloc(ptr, size);
 921   GET_MALLOC_STACK_TRACE;
 922   return msan_realloc(ptr, size, &stack);
 923 }
 924
 925 INTERCEPTOR(void *, reallocarray, void *ptr, SIZE_T nmemb, SIZE_T size) {
 926   GET_MALLOC_STACK_TRACE;
 927   return msan_reallocarray(ptr, nmemb, size, &stack);
 928 }
 929
 930 INTERCEPTOR(void *, malloc, SIZE_T size) {
 931   if (DlsymAlloc::Use())
 932     return DlsymAlloc::Allocate(size);
 933   GET_MALLOC_STACK_TRACE;
 934   return msan_malloc(size, &stack);
 935 }
 936
 937 void __msan_allocated_memory(const void *data, uptr size) {
 938   if (flags()->poison_in_malloc) {
 939     GET_MALLOC_STACK_TRACE;
 940     stack.tag = STACK_TRACE_TAG_POISON;
 941     PoisonMemory(data, size, &stack);
 942   }
 943 }
 944
 945 void __msan_copy_shadow(void *dest, const void *src, uptr n) {
 946   GET_STORE_STACK_TRACE;
 947   MoveShadowAndOrigin(dest, src, n, &stack);
 948 }
 949
 950 void __sanitizer_dtor_callback(const void *data, uptr size) {
 951   if (flags()->poison_in_dtor) {
 952     GET_MALLOC_STACK_TRACE;
 953     stack.tag = STACK_TRACE_TAG_POISON;
 954     PoisonMemory(data, size, &stack);
 955   }
 956 }
 957
 958 void __sanitizer_dtor_callback_fields(const void *data, uptr size) {
 959   if (flags()->poison_in_dtor) {
 960     GET_MALLOC_STACK_TRACE;
 961     stack.tag = STACK_TRACE_TAG_FIELDS;
 962     PoisonMemory(data, size, &stack);
 963   }
 964 }
 965
 966 void __sanitizer_dtor_callback_vptr(const void *data) {
 967   if (flags()->poison_in_dtor) {
 968     GET_MALLOC_STACK_TRACE;
 969     stack.tag = STACK_TRACE_TAG_VPTR;
 970     PoisonMemory(data, sizeof(void *), &stack);
 971   }
 972 }
 973
 974 template <class Mmap>
 975 static void *mmap_interceptor(Mmap real_mmap, void *addr, SIZE_T length,
 976                               int prot, int flags, int fd, OFF64_T offset) {
 977   SIZE_T rounded_length = RoundUpTo(length, GetPageSize());
 978   void *end_addr = (char *)addr + (rounded_length - 1);
 979   if (addr && (!MEM_IS_APP(addr) || !MEM_IS_APP(end_addr))) {
 980     if (flags & map_fixed) {
 981       errno = errno_EINVAL;
 982       return (void *)-1;
 983     } else {
 984       addr = nullptr;
 985     }
 986   }
 987   void *res = real_mmap(addr, length, prot, flags, fd, offset);
 988   if (res != (void *)-1) {
 989     void *end_res = (char *)res + (rounded_length - 1);
 990     if (MEM_IS_APP(res) && MEM_IS_APP(end_res)) {
 991       __msan_unpoison(res, rounded_length);
 992     } else {
 993       // Application has attempted to map more memory than is supported by
 994       // MSAN. Act as if we ran out of memory.
 995       internal_munmap(res, length);
 996       errno = errno_ENOMEM;
 997       return (void *)-1;
 998     }
 999   }
1000   return res;
1001 }
1002
1003 INTERCEPTOR(int, getrusage, int who, void *usage) {
1004   ENSURE_MSAN_INITED();
1005   int res = REAL(getrusage)(who, usage);
1006   if (res == 0) {
1007     __msan_unpoison(usage, __sanitizer::struct_rusage_sz);
1008   }
1009   return res;
1010 }
1011
1012 class SignalHandlerScope {
1013  public:
1014   SignalHandlerScope() {
1015     if (MsanThread *t = GetCurrentThread())
1016       t->EnterSignalHandler();
1017   }
1018   ~SignalHandlerScope() {
1019     if (MsanThread *t = GetCurrentThread())
1020       t->LeaveSignalHandler();
1021   }
1022 };
1023
1024 // sigactions_mu guarantees atomicity of sigaction() and signal() calls.
1025 // Access to sigactions[] is gone with relaxed atomics to avoid data race with
1026 // the signal handler.
1027 const int kMaxSignals = 1024;
1028 static atomic_uintptr_t sigactions[kMaxSignals];
1029 static StaticSpinMutex sigactions_mu;
1030
1031 static void SignalHandler(int signo) {
1032   SignalHandlerScope signal_handler_scope;
1033   ScopedThreadLocalStateBackup stlsb;
1034   UnpoisonParam(1);
1035
1036   typedef void (*signal_cb)(int x);
1037   signal_cb cb =
1038       (signal_cb)atomic_load(&sigactions[signo], memory_order_relaxed);
1039   cb(signo);
1040 }
1041
1042 static void SignalAction(int signo, void *si, void *uc) {
1043   SignalHandlerScope signal_handler_scope;
1044   ScopedThreadLocalStateBackup stlsb;
1045   UnpoisonParam(3);
1046   __msan_unpoison(si, sizeof(__sanitizer_sigaction));
1047   __msan_unpoison(uc, ucontext_t_sz(uc));
1048
1049   typedef void (*sigaction_cb)(int, void *, void *);
1050   sigaction_cb cb =
1051       (sigaction_cb)atomic_load(&sigactions[signo], memory_order_relaxed);
1052   cb(signo, si, uc);
1053   CHECK_UNPOISONED(uc, ucontext_t_sz(uc));
1054 }
1055
1056 static void read_sigaction(const __sanitizer_sigaction *act) {
1057   CHECK_UNPOISONED(&act->sa_flags, sizeof(act->sa_flags));
1058   if (act->sa_flags & __sanitizer::sa_siginfo)
1059     CHECK_UNPOISONED(&act->sigaction, sizeof(act->sigaction));
1060   else
1061     CHECK_UNPOISONED(&act->handler, sizeof(act->handler));
1062   CHECK_UNPOISONED(&act->sa_mask, sizeof(act->sa_mask));
1063 }
1064
1065 extern "C" int pthread_attr_init(void *attr);
1066 extern "C" int pthread_attr_destroy(void *attr);
1067
1068 static void *MsanThreadStartFunc(void *arg) {
1069   MsanThread *t = (MsanThread *)arg;
1070   SetCurrentThread(t);
1071   t->Init();
1072   SetSigProcMask(&t->starting_sigset_, nullptr);
1073   return t->ThreadStart();
1074 }
1075
1076 INTERCEPTOR(int, pthread_create, void *th, void *attr, void *(*callback)(void*),
1077             void * param) {
1078   ENSURE_MSAN_INITED(); // for GetTlsSize()
1079   __sanitizer_pthread_attr_t myattr;
1080   if (!attr) {
1081     pthread_attr_init(&myattr);
1082     attr = &myattr;
1083   }
1084
1085   AdjustStackSize(attr);
1086
1087   MsanThread *t = MsanThread::Create(callback, param);
1088   ScopedBlockSignals block(&t->starting_sigset_);
1089   int res = REAL(pthread_create)(th, attr, MsanThreadStartFunc, t);
1090
1091   if (attr == &myattr)
1092     pthread_attr_destroy(&myattr);
1093   if (!res) {
1094     __msan_unpoison(th, __sanitizer::pthread_t_sz);
1095   }
1096   return res;
1097 }
1098
1099 INTERCEPTOR(int, pthread_key_create, __sanitizer_pthread_key_t *key,
1100             void (*dtor)(void *value)) {
1101   if (msan_init_is_running) return REAL(pthread_key_create)(key, dtor);
1102   ENSURE_MSAN_INITED();
1103   int res = REAL(pthread_key_create)(key, dtor);
1104   if (!res && key)
1105     __msan_unpoison(key, sizeof(*key));
1106   return res;
1107 }
1108
1109 #if SANITIZER_NETBSD
1110 INTERCEPTOR(int, __libc_thr_keycreate, __sanitizer_pthread_key_t *m,
1111             void (*dtor)(void *value))
1112 ALIAS(WRAPPER_NAME(pthread_key_create));
1113 #endif
1114
1115 INTERCEPTOR(int, pthread_join, void *th, void **retval) {
1116   ENSURE_MSAN_INITED();
1117   int res = REAL(pthread_join)(th, retval);
1118   if (!res && retval)
1119     __msan_unpoison(retval, sizeof(*retval));
1120   return res;
1121 }
1122
1123 DEFINE_REAL_PTHREAD_FUNCTIONS
1124
1125 extern char *tzname[2];
1126
1127 INTERCEPTOR(void, tzset, int fake) {
1128   ENSURE_MSAN_INITED();
1129   InterceptorScope interceptor_scope;
1130   REAL(tzset)(fake);
1131   if (tzname[0])
1132     __msan_unpoison(tzname[0], internal_strlen(tzname[0]) + 1);
1133   if (tzname[1])
1134     __msan_unpoison(tzname[1], internal_strlen(tzname[1]) + 1);
1135   return;
1136 }
1137
1138 struct MSanAtExitRecord {
1139   void (*func)(void *arg);
1140   void *arg;
1141 };
1142
1143 struct InterceptorContext {
1144   Mutex atexit_mu;
1145   Vector<struct MSanAtExitRecord *> AtExitStack;
1146
1147   InterceptorContext()
1148       : AtExitStack() {
1149   }
1150 };
1151
1152 static ALIGNED(64) char interceptor_placeholder[sizeof(InterceptorContext)];
1153 InterceptorContext *interceptor_ctx() {
1154   return reinterpret_cast<InterceptorContext*>(&interceptor_placeholder[0]);
1155 }
1156
1157 void MSanAtExitWrapper() {
1158   MSanAtExitRecord *r;
1159   {
1160     Lock l(&interceptor_ctx()->atexit_mu);
1161
1162     uptr element = interceptor_ctx()->AtExitStack.Size() - 1;
1163     r = interceptor_ctx()->AtExitStack[element];
1164     interceptor_ctx()->AtExitStack.PopBack();
1165   }
1166
1167   UnpoisonParam(1);
1168   ((void(*)())r->func)();
1169   InternalFree(r);
1170 }
1171
1172 void MSanCxaAtExitWrapper(void *arg) {
1173   UnpoisonParam(1);
1174   MSanAtExitRecord *r = (MSanAtExitRecord *)arg;
1175   // libc before 2.27 had race which caused occasional double handler execution
1176   // https://sourceware.org/ml/libc-alpha/2017-08/msg01204.html
1177   if (!r->func)
1178     return;
1179   r->func(r->arg);
1180   r->func = nullptr;
1181 }
1182
1183 static int setup_at_exit_wrapper(void(*f)(), void *arg, void *dso);
1184
1185 // Unpoison argument shadow for C++ module destructors.
1186 INTERCEPTOR(int, __cxa_atexit, void (*func)(void *), void *arg,
1187             void *dso_handle) {
1188   if (msan_init_is_running) return REAL(__cxa_atexit)(func, arg, dso_handle);
1189   return setup_at_exit_wrapper((void(*)())func, arg, dso_handle);
1190 }
1191
1192 // Unpoison argument shadow for C++ module destructors.
1193 INTERCEPTOR(int, atexit, void (*func)()) {
1194   // Avoid calling real atexit as it is unreachable on at least on Linux.
1195   if (msan_init_is_running)
1196     return REAL(__cxa_atexit)((void (*)(void *a))func, 0, 0);
1197   return setup_at_exit_wrapper((void(*)())func, 0, 0);
1198 }
1199
1200 static int setup_at_exit_wrapper(void(*f)(), void *arg, void *dso) {
1201   ENSURE_MSAN_INITED();
1202   MSanAtExitRecord *r =
1203       (MSanAtExitRecord *)InternalAlloc(sizeof(MSanAtExitRecord));
1204   r->func = (void(*)(void *a))f;
1205   r->arg = arg;
1206   int res;
1207   if (!dso) {
1208     // NetBSD does not preserve the 2nd argument if dso is equal to 0
1209     // Store ctx in a local stack-like structure
1210
1211     Lock l(&interceptor_ctx()->atexit_mu);
1212
1213     res = REAL(__cxa_atexit)((void (*)(void *a))MSanAtExitWrapper, 0, 0);
1214     if (!res) {
1215       interceptor_ctx()->AtExitStack.PushBack(r);
1216     }
1217   } else {
1218     res = REAL(__cxa_atexit)(MSanCxaAtExitWrapper, r, dso);
1219   }
1220   return res;
1221 }
1222
1223 static void BeforeFork() {
1224   StackDepotLockAll();
1225   ChainedOriginDepotLockAll();
1226 }
1227
1228 static void AfterFork() {
1229   ChainedOriginDepotUnlockAll();
1230   StackDepotUnlockAll();
1231 }
1232
1233 INTERCEPTOR(int, fork, void) {
1234   ENSURE_MSAN_INITED();
1235   BeforeFork();
1236   int pid = REAL(fork)();
1237   AfterFork();
1238   return pid;
1239 }
1240
1241 // NetBSD ships with openpty(3) in -lutil, that needs to be prebuilt explicitly
1242 // with MSan.
1243 #if SANITIZER_LINUX
1244 INTERCEPTOR(int, openpty, int *aparent, int *aworker, char *name,
1245             const void *termp, const void *winp) {
1246   ENSURE_MSAN_INITED();
1247   InterceptorScope interceptor_scope;
1248   int res = REAL(openpty)(aparent, aworker, name, termp, winp);
1249   if (!res) {
1250     __msan_unpoison(aparent, sizeof(*aparent));
1251     __msan_unpoison(aworker, sizeof(*aworker));
1252   }
1253   return res;
1254 }
1255 #define MSAN_MAYBE_INTERCEPT_OPENPTY INTERCEPT_FUNCTION(openpty)
1256 #else
1257 #define MSAN_MAYBE_INTERCEPT_OPENPTY
1258 #endif
1259
1260 // NetBSD ships with forkpty(3) in -lutil, that needs to be prebuilt explicitly
1261 // with MSan.
1262 #if SANITIZER_LINUX
1263 INTERCEPTOR(int, forkpty, int *aparent, char *name, const void *termp,
1264             const void *winp) {
1265   ENSURE_MSAN_INITED();
1266   InterceptorScope interceptor_scope;
1267   int res = REAL(forkpty)(aparent, name, termp, winp);
1268   if (res != -1)
1269     __msan_unpoison(aparent, sizeof(*aparent));
1270   return res;
1271 }
1272 #define MSAN_MAYBE_INTERCEPT_FORKPTY INTERCEPT_FUNCTION(forkpty)
1273 #else
1274 #define MSAN_MAYBE_INTERCEPT_FORKPTY
1275 #endif
1276
1277 struct MSanInterceptorContext {
1278   bool in_interceptor_scope;
1279 };
1280
1281 namespace __msan {
1282
1283 int OnExit() {
1284   // FIXME: ask frontend whether we need to return failure.
1285   return 0;
1286 }
1287
1288 } // namespace __msan
1289
1290 // A version of CHECK_UNPOISONED using a saved scope value. Used in common
1291 // interceptors.
1292 #define CHECK_UNPOISONED_CTX(ctx, x, n)                         \
1293   do {                                                          \
1294     if (!((MSanInterceptorContext *)ctx)->in_interceptor_scope) \
1295       CHECK_UNPOISONED_0(x, n);                                 \
1296   } while (0)
1297
1298 #define MSAN_INTERCEPT_FUNC(name)                                       \
1299   do {                                                                  \
1300     if (!INTERCEPT_FUNCTION(name))                                      \
1301       VReport(1, "MemorySanitizer: failed to intercept '%s'\n", #name); \
1302   } while (0)
1303
1304 #define MSAN_INTERCEPT_FUNC_VER(name, ver)                                 \
1305   do {                                                                     \
1306     if (!INTERCEPT_FUNCTION_VER(name, ver))                                \
1307       VReport(1, "MemorySanitizer: failed to intercept '%s@@%s'\n", #name, \
1308               ver);                                                        \
1309   } while (0)
1310 #define MSAN_INTERCEPT_FUNC_VER_UNVERSIONED_FALLBACK(name, ver)             \
1311   do {                                                                      \
1312     if (!INTERCEPT_FUNCTION_VER(name, ver) && !INTERCEPT_FUNCTION(name))    \
1313       VReport(1, "MemorySanitizer: failed to intercept '%s@@%s' or '%s'\n", \
1314               #name, ver, #name);                                           \
1315   } while (0)
1316
1317 #define COMMON_INTERCEPT_FUNCTION(name) MSAN_INTERCEPT_FUNC(name)
1318 #define COMMON_INTERCEPT_FUNCTION_VER(name, ver) \
1319   MSAN_INTERCEPT_FUNC_VER(name, ver)
1320 #define COMMON_INTERCEPT_FUNCTION_VER_UNVERSIONED_FALLBACK(name, ver) \
1321   MSAN_INTERCEPT_FUNC_VER_UNVERSIONED_FALLBACK(name, ver)
1322 #define COMMON_INTERCEPTOR_UNPOISON_PARAM(count)  \
1323   UnpoisonParam(count)
1324 #define COMMON_INTERCEPTOR_WRITE_RANGE(ctx, ptr, size) \
1325   __msan_unpoison(ptr, size)
1326 #define COMMON_INTERCEPTOR_READ_RANGE(ctx, ptr, size) \
1327   CHECK_UNPOISONED_CTX(ctx, ptr, size)
1328 #define COMMON_INTERCEPTOR_INITIALIZE_RANGE(ptr, size) \
1329   __msan_unpoison(ptr, size)
1330 #define COMMON_INTERCEPTOR_ENTER(ctx, func, ...)              \
1331   if (msan_init_is_running)                                   \
1332     return REAL(func)(__VA_ARGS__);                           \
1333   ENSURE_MSAN_INITED();                                       \
1334   MSanInterceptorContext msan_ctx = {IsInInterceptorScope()}; \
1335   ctx = (void *)&msan_ctx;                                    \
1336   (void)ctx;                                                  \
1337   InterceptorScope interceptor_scope;                         \
1338   __msan_unpoison(__errno_location(), sizeof(int));
1339 #define COMMON_INTERCEPTOR_DIR_ACQUIRE(ctx, path) \
1340   do {                                            \
1341   } while (false)
1342 #define COMMON_INTERCEPTOR_FD_ACQUIRE(ctx, fd) \
1343   do {                                         \
1344   } while (false)
1345 #define COMMON_INTERCEPTOR_FD_RELEASE(ctx, fd) \
1346   do {                                         \
1347   } while (false)
1348 #define COMMON_INTERCEPTOR_FD_SOCKET_ACCEPT(ctx, fd, newfd) \
1349   do {                                                      \
1350   } while (false)
1351 #define COMMON_INTERCEPTOR_SET_THREAD_NAME(ctx, name) \
1352   do {                                                \
1353   } while (false)  // FIXME
1354 #define COMMON_INTERCEPTOR_SET_PTHREAD_NAME(ctx, thread, name) \
1355   do {                                                         \
1356   } while (false)  // FIXME
1357 #define COMMON_INTERCEPTOR_BLOCK_REAL(name) REAL(name)
1358 #define COMMON_INTERCEPTOR_ON_EXIT(ctx) OnExit()
1359 #define COMMON_INTERCEPTOR_LIBRARY_LOADED(filename, handle)                    \
1360   do {                                                                         \
1361     link_map *map = GET_LINK_MAP_BY_DLOPEN_HANDLE((handle));                   \
1362     if (filename && map)                                                       \
1363       ForEachMappedRegion(map, __msan_unpoison);                               \
1364   } while (false)
1365
1366 #define COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED (!msan_inited)
1367
1368 #define COMMON_INTERCEPTOR_GET_TLS_RANGE(begin, end)                           \
1369   if (MsanThread *t = GetCurrentThread()) {                                    \
1370     *begin = t->tls_begin();                                                   \
1371     *end = t->tls_end();                                                       \
1372   } else {                                                                     \
1373     *begin = *end = 0;                                                         \
1374   }
1375
1376 #define COMMON_INTERCEPTOR_MEMSET_IMPL(ctx, block, c, size) \
1377   {                                                         \
1378     (void)ctx;                                              \
1379     return __msan_memset(block, c, size);                   \
1380   }
1381 #define COMMON_INTERCEPTOR_MEMMOVE_IMPL(ctx, to, from, size) \
1382   {                                                          \
1383     (void)ctx;                                               \
1384     return __msan_memmove(to, from, size);                   \
1385   }
1386 #define COMMON_INTERCEPTOR_MEMCPY_IMPL(ctx, to, from, size) \
1387   {                                                         \
1388     (void)ctx;                                              \
1389     return __msan_memcpy(to, from, size);                   \
1390   }
1391
1392 #define COMMON_INTERCEPTOR_COPY_STRING(ctx, to, from, size) \
1393   do {                                                      \
1394     GET_STORE_STACK_TRACE;                                  \
1395     CopyShadowAndOrigin(to, from, size, &stack);            \
1396     __msan_unpoison(to + size, 1);                          \
1397   } while (false)
1398
1399 #define COMMON_INTERCEPTOR_MMAP_IMPL(ctx, mmap, addr, length, prot, flags, fd, \
1400                                      offset)                                   \
1401   do {                                                                         \
1402     return mmap_interceptor(REAL(mmap), addr, sz, prot, flags, fd, off);       \
1403   } while (false)
1404
1405 #include "sanitizer_common/sanitizer_platform_interceptors.h"
1406 #include "sanitizer_common/sanitizer_common_interceptors.inc"
1407
1408 static uptr signal_impl(int signo, uptr cb);
1409 static int sigaction_impl(int signo, const __sanitizer_sigaction *act,
1410                           __sanitizer_sigaction *oldact);
1411
1412 #define SIGNAL_INTERCEPTOR_SIGACTION_IMPL(signo, act, oldact) \
1413   { return sigaction_impl(signo, act, oldact); }
1414
1415 #define SIGNAL_INTERCEPTOR_SIGNAL_IMPL(func, signo, handler) \
1416   {                                                          \
1417     handler = signal_impl(signo, handler);                   \
1418     InterceptorScope interceptor_scope;                      \
1419     return REAL(func)(signo, handler);                       \
1420   }
1421
1422 #include "sanitizer_common/sanitizer_signal_interceptors.inc"
1423
1424 static int sigaction_impl(int signo, const __sanitizer_sigaction *act,
1425                           __sanitizer_sigaction *oldact) {
1426   ENSURE_MSAN_INITED();
1427   if (signo <= 0 || signo >= kMaxSignals) {
1428     errno = errno_EINVAL;
1429     return -1;
1430   }
1431   if (act) read_sigaction(act);
1432   int res;
1433   if (flags()->wrap_signals) {
1434     SpinMutexLock lock(&sigactions_mu);
1435     uptr old_cb = atomic_load(&sigactions[signo], memory_order_relaxed);
1436     __sanitizer_sigaction new_act;
1437     __sanitizer_sigaction *pnew_act = act ? &new_act : nullptr;
1438     if (act) {
1439       REAL(memcpy)(pnew_act, act, sizeof(__sanitizer_sigaction));
1440       uptr cb = (uptr)pnew_act->sigaction;
1441       uptr new_cb = (pnew_act->sa_flags & __sanitizer::sa_siginfo)
1442                         ? (uptr)SignalAction
1443                         : (uptr)SignalHandler;
1444       if (cb != __sanitizer::sig_ign && cb != __sanitizer::sig_dfl) {
1445         atomic_store(&sigactions[signo], cb, memory_order_relaxed);
1446         pnew_act->sigaction = (decltype(pnew_act->sigaction))new_cb;
1447       }
1448     }
1449     res = REAL(SIGACTION_SYMNAME)(signo, pnew_act, oldact);
1450     if (res == 0 && oldact) {
1451       uptr cb = (uptr)oldact->sigaction;
1452       if (cb == (uptr)SignalAction || cb == (uptr)SignalHandler) {
1453         oldact->sigaction = (decltype(oldact->sigaction))old_cb;
1454       }
1455     }
1456   } else {
1457     res = REAL(SIGACTION_SYMNAME)(signo, act, oldact);
1458   }
1459
1460   if (res == 0 && oldact) {
1461     __msan_unpoison(oldact, sizeof(__sanitizer_sigaction));
1462   }
1463   return res;
1464 }
1465
1466 static uptr signal_impl(int signo, uptr cb) {
1467   ENSURE_MSAN_INITED();
1468   if (signo <= 0 || signo >= kMaxSignals) {
1469     errno = errno_EINVAL;
1470     return -1;
1471   }
1472   if (flags()->wrap_signals) {
1473     SpinMutexLock lock(&sigactions_mu);
1474     if (cb != __sanitizer::sig_ign && cb != __sanitizer::sig_dfl) {
1475       atomic_store(&sigactions[signo], cb, memory_order_relaxed);
1476       cb = (uptr)&SignalHandler;
1477     }
1478   }
1479   return cb;
1480 }
1481
1482 #define COMMON_SYSCALL_PRE_READ_RANGE(p, s) CHECK_UNPOISONED(p, s)
1483 #define COMMON_SYSCALL_PRE_WRITE_RANGE(p, s) \
1484   do {                                       \
1485   } while (false)
1486 #define COMMON_SYSCALL_POST_READ_RANGE(p, s) \
1487   do {                                       \
1488   } while (false)
1489 #define COMMON_SYSCALL_POST_WRITE_RANGE(p, s) __msan_unpoison(p, s)
1490 #include "sanitizer_common/sanitizer_common_syscalls.inc"
1491 #include "sanitizer_common/sanitizer_syscalls_netbsd.inc"
1492
1493 INTERCEPTOR(const char *, strsignal, int sig) {
1494   void *ctx;
1495   COMMON_INTERCEPTOR_ENTER(ctx, strsignal, sig);
1496   const char *res = REAL(strsignal)(sig);
1497   if (res)
1498     __msan_unpoison(res, internal_strlen(res) + 1);
1499   return res;
1500 }
1501
1502 struct dlinfo {
1503   char *dli_fname;
1504   void *dli_fbase;
1505   char *dli_sname;
1506   void *dli_saddr;
1507 };
1508
1509 INTERCEPTOR(int, dladdr, void *addr, dlinfo *info) {
1510   void *ctx;
1511   COMMON_INTERCEPTOR_ENTER(ctx, dladdr, addr, info);
1512   int res = REAL(dladdr)(addr, info);
1513   if (res != 0) {
1514     __msan_unpoison(info, sizeof(*info));
1515     if (info->dli_fname)
1516       __msan_unpoison(info->dli_fname, internal_strlen(info->dli_fname) + 1);
1517     if (info->dli_sname)
1518       __msan_unpoison(info->dli_sname, internal_strlen(info->dli_sname) + 1);
1519   }
1520   return res;
1521 }
1522
1523 INTERCEPTOR(char *, dlerror, int fake) {
1524   void *ctx;
1525   COMMON_INTERCEPTOR_ENTER(ctx, dlerror, fake);
1526   char *res = REAL(dlerror)(fake);
1527   if (res)
1528     __msan_unpoison(res, internal_strlen(res) + 1);
1529   return res;
1530 }
1531
1532 typedef int (*dl_iterate_phdr_cb)(__sanitizer_dl_phdr_info *info, SIZE_T size,
1533                                   void *data);
1534 struct dl_iterate_phdr_data {
1535   dl_iterate_phdr_cb callback;
1536   void *data;
1537 };
1538
1539 static int msan_dl_iterate_phdr_cb(__sanitizer_dl_phdr_info *info, SIZE_T size,
1540                                    void *data) {
1541   if (info) {
1542     __msan_unpoison(info, size);
1543     if (info->dlpi_phdr && info->dlpi_phnum)
1544       __msan_unpoison(info->dlpi_phdr, struct_ElfW_Phdr_sz * info->dlpi_phnum);
1545     if (info->dlpi_name)
1546       __msan_unpoison(info->dlpi_name, internal_strlen(info->dlpi_name) + 1);
1547   }
1548   dl_iterate_phdr_data *cbdata = (dl_iterate_phdr_data *)data;
1549   UnpoisonParam(3);
1550   return cbdata->callback(info, size, cbdata->data);
1551 }
1552
1553 INTERCEPTOR(void *, shmat, int shmid, const void *shmaddr, int shmflg) {
1554   ENSURE_MSAN_INITED();
1555   void *p = REAL(shmat)(shmid, shmaddr, shmflg);
1556   if (p != (void *)-1) {
1557     __sanitizer_shmid_ds ds;
1558     int res = REAL(shmctl)(shmid, shmctl_ipc_stat, &ds);
1559     if (!res) {
1560       __msan_unpoison(p, ds.shm_segsz);
1561     }
1562   }
1563   return p;
1564 }
1565
1566 INTERCEPTOR(int, dl_iterate_phdr, dl_iterate_phdr_cb callback, void *data) {
1567   void *ctx;
1568   COMMON_INTERCEPTOR_ENTER(ctx, dl_iterate_phdr, callback, data);
1569   dl_iterate_phdr_data cbdata;
1570   cbdata.callback = callback;
1571   cbdata.data = data;
1572   int res = REAL(dl_iterate_phdr)(msan_dl_iterate_phdr_cb, (void *)&cbdata);
1573   return res;
1574 }
1575
1576 // wchar_t *wcschr(const wchar_t *wcs, wchar_t wc);
1577 INTERCEPTOR(wchar_t *, wcschr, void *s, wchar_t wc, void *ps) {
1578   ENSURE_MSAN_INITED();
1579   wchar_t *res = REAL(wcschr)(s, wc, ps);
1580   return res;
1581 }
1582
1583 // wchar_t *wcscpy(wchar_t *dest, const wchar_t *src);
1584 INTERCEPTOR(wchar_t *, wcscpy, wchar_t *dest, const wchar_t *src) {
1585   ENSURE_MSAN_INITED();
1586   GET_STORE_STACK_TRACE;
1587   wchar_t *res = REAL(wcscpy)(dest, src);
1588   CopyShadowAndOrigin(dest, src, sizeof(wchar_t) * (internal_wcslen(src) + 1),
1589                       &stack);
1590   return res;
1591 }
1592
1593 INTERCEPTOR(wchar_t *, wcsncpy, wchar_t *dest, const wchar_t *src, SIZE_T n) {
1594   ENSURE_MSAN_INITED();
1595   GET_STORE_STACK_TRACE;
1596   SIZE_T copy_size = internal_wcsnlen(src, n);
1597   if (copy_size < n) copy_size++;           // trailing \0
1598   wchar_t *res = REAL(wcsncpy)(dest, src, n);
1599   CopyShadowAndOrigin(dest, src, copy_size * sizeof(wchar_t), &stack);
1600   __msan_unpoison(dest + copy_size, (n - copy_size) * sizeof(wchar_t));
1601   return res;
1602 }
1603
1604 // These interface functions reside here so that they can use
1605 // REAL(memset), etc.
1606 void __msan_unpoison(const void *a, uptr size) {
1607   if (!MEM_IS_APP(a)) return;
1608   SetShadow(a, size, 0);
1609 }
1610
1611 void __msan_poison(const void *a, uptr size) {
1612   if (!MEM_IS_APP(a)) return;
1613   SetShadow(a, size, __msan::flags()->poison_heap_with_zeroes ? 0 : -1);
1614 }
1615
1616 void __msan_poison_stack(void *a, uptr size) {
1617   if (!MEM_IS_APP(a)) return;
1618   SetShadow(a, size, __msan::flags()->poison_stack_with_zeroes ? 0 : -1);
1619 }
1620
1621 void __msan_unpoison_param(uptr n) { UnpoisonParam(n); }
1622
1623 void __msan_clear_and_unpoison(void *a, uptr size) {
1624   REAL(memset)(a, 0, size);
1625   SetShadow(a, size, 0);
1626 }
1627
1628 void *__msan_memcpy(void *dest, const void *src, SIZE_T n) {
1629   if (!msan_inited) return internal_memcpy(dest, src, n);
1630   if (msan_init_is_running || __msan::IsInSymbolizerOrUnwider())
1631     return REAL(memcpy)(dest, src, n);
1632   ENSURE_MSAN_INITED();
1633   GET_STORE_STACK_TRACE;
1634   void *res = REAL(memcpy)(dest, src, n);
1635   CopyShadowAndOrigin(dest, src, n, &stack);
1636   return res;
1637 }
1638
1639 void *__msan_memset(void *s, int c, SIZE_T n) {
1640   if (!msan_inited) return internal_memset(s, c, n);
1641   if (msan_init_is_running) return REAL(memset)(s, c, n);
1642   ENSURE_MSAN_INITED();
1643   void *res = REAL(memset)(s, c, n);
1644   __msan_unpoison(s, n);
1645   return res;
1646 }
1647
1648 void *__msan_memmove(void *dest, const void *src, SIZE_T n) {
1649   if (!msan_inited) return internal_memmove(dest, src, n);
1650   if (msan_init_is_running) return REAL(memmove)(dest, src, n);
1651   ENSURE_MSAN_INITED();
1652   GET_STORE_STACK_TRACE;
1653   void *res = REAL(memmove)(dest, src, n);
1654   MoveShadowAndOrigin(dest, src, n, &stack);
1655   return res;
1656 }
1657
1658 void __msan_unpoison_string(const char* s) {
1659   if (!MEM_IS_APP(s)) return;
1660   __msan_unpoison(s, internal_strlen(s) + 1);
1661 }
1662
1663 namespace __msan {
1664
1665 void InitializeInterceptors() {
1666   static int inited = 0;
1667   CHECK_EQ(inited, 0);
1668
1669   new(interceptor_ctx()) InterceptorContext();
1670
1671   InitializeCommonInterceptors();
1672   InitializeSignalInterceptors();
1673
1674   INTERCEPT_FUNCTION(posix_memalign);
1675   MSAN_MAYBE_INTERCEPT_MEMALIGN;
1676   MSAN_MAYBE_INTERCEPT___LIBC_MEMALIGN;
1677   INTERCEPT_FUNCTION(valloc);
1678   MSAN_MAYBE_INTERCEPT_PVALLOC;
1679   INTERCEPT_FUNCTION(malloc);
1680   INTERCEPT_FUNCTION(calloc);
1681   INTERCEPT_FUNCTION(realloc);
1682   INTERCEPT_FUNCTION(reallocarray);
1683   INTERCEPT_FUNCTION(free);
1684   MSAN_MAYBE_INTERCEPT_CFREE;
1685   MSAN_MAYBE_INTERCEPT_MALLOC_USABLE_SIZE;
1686   MSAN_MAYBE_INTERCEPT_MALLINFO;
1687   MSAN_MAYBE_INTERCEPT_MALLOPT;
1688   MSAN_MAYBE_INTERCEPT_MALLOC_STATS;
1689   INTERCEPT_FUNCTION(fread);
1690   MSAN_MAYBE_INTERCEPT_FREAD_UNLOCKED;
1691   INTERCEPT_FUNCTION(memccpy);
1692   MSAN_MAYBE_INTERCEPT_MEMPCPY;
1693   INTERCEPT_FUNCTION(bcopy);
1694   INTERCEPT_FUNCTION(wmemset);
1695   INTERCEPT_FUNCTION(wmemcpy);
1696   MSAN_MAYBE_INTERCEPT_WMEMPCPY;
1697   INTERCEPT_FUNCTION(wmemmove);
1698   INTERCEPT_FUNCTION(strcpy);
1699   MSAN_MAYBE_INTERCEPT_STPCPY;
1700   MSAN_MAYBE_INTERCEPT_STPNCPY;
1701   INTERCEPT_FUNCTION(strdup);
1702   MSAN_MAYBE_INTERCEPT___STRDUP;
1703   INTERCEPT_FUNCTION(strncpy);
1704   MSAN_MAYBE_INTERCEPT_GCVT;
1705   INTERCEPT_FUNCTION(strcat);
1706   INTERCEPT_FUNCTION(strncat);
1707   INTERCEPT_STRTO(strtod);
1708   INTERCEPT_STRTO(strtof);
1709   INTERCEPT_STRTO(strtold);
1710   INTERCEPT_STRTO(strtol);
1711   INTERCEPT_STRTO(strtoul);
1712   INTERCEPT_STRTO(strtoll);
1713   INTERCEPT_STRTO(strtoull);
1714   INTERCEPT_STRTO(strtouq);
1715   INTERCEPT_STRTO(wcstod);
1716   INTERCEPT_STRTO(wcstof);
1717   INTERCEPT_STRTO(wcstold);
1718   INTERCEPT_STRTO(wcstol);
1719   INTERCEPT_STRTO(wcstoul);
1720   INTERCEPT_STRTO(wcstoll);
1721   INTERCEPT_STRTO(wcstoull);
1722 #ifdef SANITIZER_NLDBL_VERSION
1723   INTERCEPT_FUNCTION_VER(vswprintf, SANITIZER_NLDBL_VERSION);
1724   INTERCEPT_FUNCTION_VER(swprintf, SANITIZER_NLDBL_VERSION);
1725 #else
1726   INTERCEPT_FUNCTION(vswprintf);
1727   INTERCEPT_FUNCTION(swprintf);
1728 #endif
1729   INTERCEPT_FUNCTION(strftime);
1730   INTERCEPT_FUNCTION(strftime_l);
1731   MSAN_MAYBE_INTERCEPT___STRFTIME_L;
1732   INTERCEPT_FUNCTION(wcsftime);
1733   INTERCEPT_FUNCTION(wcsftime_l);
1734   MSAN_MAYBE_INTERCEPT___WCSFTIME_L;
1735   INTERCEPT_FUNCTION(mbtowc);
1736   INTERCEPT_FUNCTION(mbrtowc);
1737   INTERCEPT_FUNCTION(wcslen);
1738   INTERCEPT_FUNCTION(wcsnlen);
1739   INTERCEPT_FUNCTION(wcschr);
1740   INTERCEPT_FUNCTION(wcscpy);
1741   INTERCEPT_FUNCTION(wcsncpy);
1742   INTERCEPT_FUNCTION(wcscmp);
1743   INTERCEPT_FUNCTION(getenv);
1744   INTERCEPT_FUNCTION(setenv);
1745   INTERCEPT_FUNCTION(putenv);
1746   INTERCEPT_FUNCTION(gettimeofday);
1747   MSAN_MAYBE_INTERCEPT_FCVT;
1748   MSAN_MAYBE_INTERCEPT_FSTAT;
1749   MSAN_MAYBE_INTERCEPT_FSTAT64;
1750   MSAN_MAYBE_INTERCEPT___FXSTAT;
1751   MSAN_MAYBE_INTERCEPT_FSTATAT;
1752   MSAN_MAYBE_INTERCEPT_FSTATAT64;
1753   MSAN_MAYBE_INTERCEPT___FXSTATAT;
1754   MSAN_MAYBE_INTERCEPT___FXSTAT64;
1755   MSAN_MAYBE_INTERCEPT___FXSTATAT64;
1756   INTERCEPT_FUNCTION(pipe);
1757   INTERCEPT_FUNCTION(pipe2);
1758   INTERCEPT_FUNCTION(socketpair);
1759   MSAN_MAYBE_INTERCEPT_FGETS_UNLOCKED;
1760   INTERCEPT_FUNCTION(getrlimit);
1761   MSAN_MAYBE_INTERCEPT___GETRLIMIT;
1762   MSAN_MAYBE_INTERCEPT_GETRLIMIT64;
1763   MSAN_MAYBE_INTERCEPT_PRLIMIT;
1764   MSAN_MAYBE_INTERCEPT_PRLIMIT64;
1765   INTERCEPT_FUNCTION(gethostname);
1766   MSAN_MAYBE_INTERCEPT_EPOLL_WAIT;
1767   MSAN_MAYBE_INTERCEPT_EPOLL_PWAIT;
1768   INTERCEPT_FUNCTION(strsignal);
1769   INTERCEPT_FUNCTION(dladdr);
1770   INTERCEPT_FUNCTION(dlerror);
1771   INTERCEPT_FUNCTION(dl_iterate_phdr);
1772   INTERCEPT_FUNCTION(getrusage);
1773 #if defined(__mips__)
1774   INTERCEPT_FUNCTION_VER(pthread_create, "GLIBC_2.2");
1775 #else
1776   INTERCEPT_FUNCTION(pthread_create);
1777 #endif
1778   INTERCEPT_FUNCTION(pthread_join);
1779   INTERCEPT_FUNCTION(pthread_key_create);
1780
1781 #if SANITIZER_NETBSD
1782   INTERCEPT_FUNCTION(__libc_thr_keycreate);
1783 #endif
1784
1785   INTERCEPT_FUNCTION(pthread_join);
1786   INTERCEPT_FUNCTION(tzset);
1787   INTERCEPT_FUNCTION(atexit);
1788   INTERCEPT_FUNCTION(__cxa_atexit);
1789   INTERCEPT_FUNCTION(shmat);
1790   INTERCEPT_FUNCTION(fork);
1791   MSAN_MAYBE_INTERCEPT_OPENPTY;
1792   MSAN_MAYBE_INTERCEPT_FORKPTY;
1793
1794   inited = 1;
1795 }
1796 } // namespace __msan