1 //===-- msan.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 // MemorySanitizer runtime.
12 //===----------------------------------------------------------------------===//
13
14 #include "msan.h"
15 #include "msan_chained_origin_depot.h"
16 #include "msan_origin.h"
17 #include "msan_report.h"
18 #include "msan_thread.h"
19 #include "msan_poisoning.h"
20 #include "sanitizer_common/sanitizer_atomic.h"
21 #include "sanitizer_common/sanitizer_common.h"
22 #include "sanitizer_common/sanitizer_flags.h"
23 #include "sanitizer_common/sanitizer_flag_parser.h"
24 #include "sanitizer_common/sanitizer_libc.h"
25 #include "sanitizer_common/sanitizer_procmaps.h"
26 #include "sanitizer_common/sanitizer_stacktrace.h"
27 #include "sanitizer_common/sanitizer_symbolizer.h"
28 #include "sanitizer_common/sanitizer_stackdepot.h"
29 #include "ubsan/ubsan_flags.h"
30 #include "ubsan/ubsan_init.h"
31
32 // ACHTUNG! No system header includes in this file.
33
34 using namespace __sanitizer;
35
36 // Globals.
37 static THREADLOCAL int msan_expect_umr = 0;
38 static THREADLOCAL int msan_expected_umr_found = 0;
39
40 // Function argument shadow. Each argument starts at the next available 8-byte
41 // aligned address.
42 SANITIZER_INTERFACE_ATTRIBUTE
43 THREADLOCAL u64 __msan_param_tls[kMsanParamTlsSize / sizeof(u64)];
44
45 // Function argument origin. Each argument starts at the same offset as the
46 // corresponding shadow in (__msan_param_tls). Slightly weird, but changing this
47 // would break compatibility with older prebuilt binaries.
48 SANITIZER_INTERFACE_ATTRIBUTE
49 THREADLOCAL u32 __msan_param_origin_tls[kMsanParamTlsSize / sizeof(u32)];
50
51 SANITIZER_INTERFACE_ATTRIBUTE
52 THREADLOCAL u64 __msan_retval_tls[kMsanRetvalTlsSize / sizeof(u64)];
53
54 SANITIZER_INTERFACE_ATTRIBUTE
55 THREADLOCAL u32 __msan_retval_origin_tls;
56
57 SANITIZER_INTERFACE_ATTRIBUTE
58 ALIGNED(16) THREADLOCAL u64 __msan_va_arg_tls[kMsanParamTlsSize / sizeof(u64)];
59
60 SANITIZER_INTERFACE_ATTRIBUTE
61 ALIGNED(16)
62 THREADLOCAL u32 __msan_va_arg_origin_tls[kMsanParamTlsSize / sizeof(u32)];
63
64 SANITIZER_INTERFACE_ATTRIBUTE
65 THREADLOCAL u64 __msan_va_arg_overflow_size_tls;
66
67 SANITIZER_INTERFACE_ATTRIBUTE
68 THREADLOCAL u32 __msan_origin_tls;
69
70 static THREADLOCAL int is_in_symbolizer;
71
72 extern "C" SANITIZER_WEAK_ATTRIBUTE const int __msan_track_origins;
73
__msan_get_track_origins()74 int __msan_get_track_origins() {
75 return &__msan_track_origins ? __msan_track_origins : 0;
76 }
77
78 extern "C" SANITIZER_WEAK_ATTRIBUTE const int __msan_keep_going;
79
80 namespace __msan {
81
EnterSymbolizer()82 void EnterSymbolizer() { ++is_in_symbolizer; }
ExitSymbolizer()83 void ExitSymbolizer() { --is_in_symbolizer; }
IsInSymbolizer()84 bool IsInSymbolizer() { return is_in_symbolizer; }
85
86 static Flags msan_flags;
87
flags()88 Flags *flags() {
89 return &msan_flags;
90 }
91
92 int msan_inited = 0;
93 bool msan_init_is_running;
94
95 int msan_report_count = 0;
96
97 // Array of stack origins.
98 // FIXME: make it resizable.
99 static const uptr kNumStackOriginDescrs = 1024 * 1024;
100 static const char *StackOriginDescr[kNumStackOriginDescrs];
101 static uptr StackOriginPC[kNumStackOriginDescrs];
102 static atomic_uint32_t NumStackOriginDescrs;
103
SetDefaults()104 void Flags::SetDefaults() {
105 #define MSAN_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue;
106 #include "msan_flags.inc"
107 #undef MSAN_FLAG
108 }
109
110 // keep_going is an old name for halt_on_error,
111 // and it has inverse meaning.
112 class FlagHandlerKeepGoing final : public FlagHandlerBase {
113 bool *halt_on_error_;
114
115 public:
FlagHandlerKeepGoing(bool * halt_on_error)116 explicit FlagHandlerKeepGoing(bool *halt_on_error)
117 : halt_on_error_(halt_on_error) {}
Parse(const char * value)118 bool Parse(const char *value) final {
119 bool tmp;
120 FlagHandler<bool> h(&tmp);
121 if (!h.Parse(value)) return false;
122 *halt_on_error_ = !tmp;
123 return true;
124 }
Format(char * buffer,uptr size)125 bool Format(char *buffer, uptr size) final {
126 const char *keep_going_str = (*halt_on_error_) ? "false" : "true";
127 return FormatString(buffer, size, keep_going_str);
128 }
129 };
130
RegisterMsanFlags(FlagParser * parser,Flags * f)131 static void RegisterMsanFlags(FlagParser *parser, Flags *f) {
132 #define MSAN_FLAG(Type, Name, DefaultValue, Description) \
133 RegisterFlag(parser, #Name, Description, &f->Name);
134 #include "msan_flags.inc"
135 #undef MSAN_FLAG
136
137 FlagHandlerKeepGoing *fh_keep_going =
138 new (FlagParser::Alloc) FlagHandlerKeepGoing(&f->halt_on_error);
139 parser->RegisterHandler("keep_going", fh_keep_going,
140 "deprecated, use halt_on_error");
141 }
142
InitializeFlags()143 static void InitializeFlags() {
144 SetCommonFlagsDefaults();
145 {
146 CommonFlags cf;
147 cf.CopyFrom(*common_flags());
148 cf.external_symbolizer_path = GetEnv("MSAN_SYMBOLIZER_PATH");
149 cf.malloc_context_size = 20;
150 cf.handle_ioctl = true;
151 // FIXME: test and enable.
152 cf.check_printf = false;
153 cf.intercept_tls_get_addr = true;
154 OverrideCommonFlags(cf);
155 }
156
157 Flags *f = flags();
158 f->SetDefaults();
159
160 FlagParser parser;
161 RegisterMsanFlags(&parser, f);
162 RegisterCommonFlags(&parser);
163
164 #if MSAN_CONTAINS_UBSAN
165 __ubsan::Flags *uf = __ubsan::flags();
166 uf->SetDefaults();
167
168 FlagParser ubsan_parser;
169 __ubsan::RegisterUbsanFlags(&ubsan_parser, uf);
170 RegisterCommonFlags(&ubsan_parser);
171 #endif
172
173 // Override from user-specified string.
174 parser.ParseString(__msan_default_options());
175 #if MSAN_CONTAINS_UBSAN
176 const char *ubsan_default_options = __ubsan_default_options();
177 ubsan_parser.ParseString(ubsan_default_options);
178 #endif
179
180 parser.ParseStringFromEnv("MSAN_OPTIONS");
181 #if MSAN_CONTAINS_UBSAN
182 ubsan_parser.ParseStringFromEnv("UBSAN_OPTIONS");
183 #endif
184
185 InitializeCommonFlags();
186
187 if (Verbosity()) ReportUnrecognizedFlags();
188
189 if (common_flags()->help) parser.PrintFlagDescriptions();
190
191 // Check if deprecated exit_code MSan flag is set.
192 if (f->exit_code != -1) {
193 if (Verbosity())
194 Printf("MSAN_OPTIONS=exit_code is deprecated! "
195 "Please use MSAN_OPTIONS=exitcode instead.\n");
196 CommonFlags cf;
197 cf.CopyFrom(*common_flags());
198 cf.exitcode = f->exit_code;
199 OverrideCommonFlags(cf);
200 }
201
202 // Check flag values:
203 if (f->origin_history_size < 0 ||
204 f->origin_history_size > Origin::kMaxDepth) {
205 Printf(
206 "Origin history size invalid: %d. Must be 0 (unlimited) or in [1, %d] "
207 "range.\n",
208 f->origin_history_size, Origin::kMaxDepth);
209 Die();
210 }
211 // Limiting to kStackDepotMaxUseCount / 2 to avoid overflow in
212 // StackDepotHandle::inc_use_count_unsafe.
213 if (f->origin_history_per_stack_limit < 0 ||
214 f->origin_history_per_stack_limit > kStackDepotMaxUseCount / 2) {
215 Printf(
216 "Origin per-stack limit invalid: %d. Must be 0 (unlimited) or in [1, "
217 "%d] range.\n",
218 f->origin_history_per_stack_limit, kStackDepotMaxUseCount / 2);
219 Die();
220 }
221 if (f->store_context_size < 1) f->store_context_size = 1;
222 }
223
PrintWarning(uptr pc,uptr bp)224 void PrintWarning(uptr pc, uptr bp) {
225 PrintWarningWithOrigin(pc, bp, __msan_origin_tls);
226 }
227
PrintWarningWithOrigin(uptr pc,uptr bp,u32 origin)228 void PrintWarningWithOrigin(uptr pc, uptr bp, u32 origin) {
229 if (msan_expect_umr) {
230 // Printf("Expected UMR\n");
231 __msan_origin_tls = origin;
232 msan_expected_umr_found = 1;
233 return;
234 }
235
236 ++msan_report_count;
237
238 GET_FATAL_STACK_TRACE_PC_BP(pc, bp);
239
240 u32 report_origin =
241 (__msan_get_track_origins() && Origin::isValidId(origin)) ? origin : 0;
242 ReportUMR(&stack, report_origin);
243
244 if (__msan_get_track_origins() && !Origin::isValidId(origin)) {
245 Printf(
246 " ORIGIN: invalid (%x). Might be a bug in MemorySanitizer origin "
247 "tracking.\n This could still be a bug in your code, too!\n",
248 origin);
249 }
250 }
251
UnpoisonParam(uptr n)252 void UnpoisonParam(uptr n) {
253 internal_memset(__msan_param_tls, 0, n * sizeof(*__msan_param_tls));
254 }
255
256 // Backup MSan runtime TLS state.
257 // Implementation must be async-signal-safe.
258 // Instances of this class may live on the signal handler stack, and data size
259 // may be an issue.
Backup()260 void ScopedThreadLocalStateBackup::Backup() {
261 va_arg_overflow_size_tls = __msan_va_arg_overflow_size_tls;
262 }
263
Restore()264 void ScopedThreadLocalStateBackup::Restore() {
265 // A lame implementation that only keeps essential state and resets the rest.
266 __msan_va_arg_overflow_size_tls = va_arg_overflow_size_tls;
267
268 internal_memset(__msan_param_tls, 0, sizeof(__msan_param_tls));
269 internal_memset(__msan_retval_tls, 0, sizeof(__msan_retval_tls));
270 internal_memset(__msan_va_arg_tls, 0, sizeof(__msan_va_arg_tls));
271 internal_memset(__msan_va_arg_origin_tls, 0,
272 sizeof(__msan_va_arg_origin_tls));
273
274 if (__msan_get_track_origins()) {
275 internal_memset(&__msan_retval_origin_tls, 0,
276 sizeof(__msan_retval_origin_tls));
277 internal_memset(__msan_param_origin_tls, 0,
278 sizeof(__msan_param_origin_tls));
279 }
280 }
281
UnpoisonThreadLocalState()282 void UnpoisonThreadLocalState() {
283 }
284
GetStackOriginDescr(u32 id,uptr * pc)285 const char *GetStackOriginDescr(u32 id, uptr *pc) {
286 CHECK_LT(id, kNumStackOriginDescrs);
287 if (pc) *pc = StackOriginPC[id];
288 return StackOriginDescr[id];
289 }
290
ChainOrigin(u32 id,StackTrace * stack)291 u32 ChainOrigin(u32 id, StackTrace *stack) {
292 MsanThread *t = GetCurrentThread();
293 if (t && t->InSignalHandler())
294 return id;
295
296 Origin o = Origin::FromRawId(id);
297 stack->tag = StackTrace::TAG_UNKNOWN;
298 Origin chained = Origin::CreateChainedOrigin(o, stack);
299 return chained.raw_id();
300 }
301
302 } // namespace __msan
303
UnwindImpl(uptr pc,uptr bp,void * context,bool request_fast,u32 max_depth)304 void __sanitizer::BufferedStackTrace::UnwindImpl(
305 uptr pc, uptr bp, void *context, bool request_fast, u32 max_depth) {
306 using namespace __msan;
307 MsanThread *t = GetCurrentThread();
308 if (!t || !StackTrace::WillUseFastUnwind(request_fast)) {
309 // Block reports from our interceptors during _Unwind_Backtrace.
310 SymbolizerScope sym_scope;
311 return Unwind(max_depth, pc, bp, context, 0, 0, false);
312 }
313 if (StackTrace::WillUseFastUnwind(request_fast))
314 Unwind(max_depth, pc, bp, nullptr, t->stack_top(), t->stack_bottom(), true);
315 else
316 Unwind(max_depth, pc, 0, context, 0, 0, false);
317 }
318
319 // Interface.
320
321 using namespace __msan;
322
323 #define MSAN_MAYBE_WARNING(type, size) \
324 void __msan_maybe_warning_##size(type s, u32 o) { \
325 GET_CALLER_PC_BP_SP; \
326 (void) sp; \
327 if (UNLIKELY(s)) { \
328 PrintWarningWithOrigin(pc, bp, o); \
329 if (__msan::flags()->halt_on_error) { \
330 Printf("Exiting\n"); \
331 Die(); \
332 } \
333 } \
334 }
335
336 MSAN_MAYBE_WARNING(u8, 1)
337 MSAN_MAYBE_WARNING(u16, 2)
338 MSAN_MAYBE_WARNING(u32, 4)
339 MSAN_MAYBE_WARNING(u64, 8)
340
341 #define MSAN_MAYBE_STORE_ORIGIN(type, size) \
342 void __msan_maybe_store_origin_##size(type s, void *p, u32 o) { \
343 if (UNLIKELY(s)) { \
344 if (__msan_get_track_origins() > 1) { \
345 GET_CALLER_PC_BP_SP; \
346 (void) sp; \
347 GET_STORE_STACK_TRACE_PC_BP(pc, bp); \
348 o = ChainOrigin(o, &stack); \
349 } \
350 *(u32 *)MEM_TO_ORIGIN((uptr)p & ~3UL) = o; \
351 } \
352 }
353
354 MSAN_MAYBE_STORE_ORIGIN(u8, 1)
355 MSAN_MAYBE_STORE_ORIGIN(u16, 2)
356 MSAN_MAYBE_STORE_ORIGIN(u32, 4)
357 MSAN_MAYBE_STORE_ORIGIN(u64, 8)
358
__msan_warning()359 void __msan_warning() {
360 GET_CALLER_PC_BP_SP;
361 (void)sp;
362 PrintWarning(pc, bp);
363 if (__msan::flags()->halt_on_error) {
364 if (__msan::flags()->print_stats)
365 ReportStats();
366 Printf("Exiting\n");
367 Die();
368 }
369 }
370
__msan_warning_noreturn()371 void __msan_warning_noreturn() {
372 GET_CALLER_PC_BP_SP;
373 (void)sp;
374 PrintWarning(pc, bp);
375 if (__msan::flags()->print_stats)
376 ReportStats();
377 Printf("Exiting\n");
378 Die();
379 }
380
__msan_warning_with_origin(u32 origin)381 void __msan_warning_with_origin(u32 origin) {
382 GET_CALLER_PC_BP_SP;
383 (void)sp;
384 PrintWarningWithOrigin(pc, bp, origin);
385 if (__msan::flags()->halt_on_error) {
386 if (__msan::flags()->print_stats)
387 ReportStats();
388 Printf("Exiting\n");
389 Die();
390 }
391 }
392
__msan_warning_with_origin_noreturn(u32 origin)393 void __msan_warning_with_origin_noreturn(u32 origin) {
394 GET_CALLER_PC_BP_SP;
395 (void)sp;
396 PrintWarningWithOrigin(pc, bp, origin);
397 if (__msan::flags()->print_stats)
398 ReportStats();
399 Printf("Exiting\n");
400 Die();
401 }
402
OnStackUnwind(const SignalContext & sig,const void *,BufferedStackTrace * stack)403 static void OnStackUnwind(const SignalContext &sig, const void *,
404 BufferedStackTrace *stack) {
405 stack->Unwind(StackTrace::GetNextInstructionPc(sig.pc), sig.bp, sig.context,
406 common_flags()->fast_unwind_on_fatal);
407 }
408
MsanOnDeadlySignal(int signo,void * siginfo,void * context)409 static void MsanOnDeadlySignal(int signo, void *siginfo, void *context) {
410 HandleDeadlySignal(siginfo, context, GetTid(), &OnStackUnwind, nullptr);
411 }
412
MsanCheckFailed(const char * file,int line,const char * cond,u64 v1,u64 v2)413 static void MsanCheckFailed(const char *file, int line, const char *cond,
414 u64 v1, u64 v2) {
415 Report("MemorySanitizer CHECK failed: %s:%d \"%s\" (0x%zx, 0x%zx)\n", file,
416 line, cond, (uptr)v1, (uptr)v2);
417 PRINT_CURRENT_STACK_CHECK();
418 Die();
419 }
420
__msan_init()421 void __msan_init() {
422 CHECK(!msan_init_is_running);
423 if (msan_inited) return;
424 msan_init_is_running = 1;
425 SanitizerToolName = "MemorySanitizer";
426
427 AvoidCVE_2016_2143();
428
429 CacheBinaryName();
430 InitializeFlags();
431
432 // Install tool-specific callbacks in sanitizer_common.
433 SetCheckFailedCallback(MsanCheckFailed);
434
435 __sanitizer_set_report_path(common_flags()->log_path);
436
437 InitializeInterceptors();
438 CheckASLR();
439 InitTlsSize();
440 InstallDeadlySignalHandlers(MsanOnDeadlySignal);
441 InstallAtExitHandler(); // Needs __cxa_atexit interceptor.
442
443 DisableCoreDumperIfNecessary();
444 if (StackSizeIsUnlimited()) {
445 VPrintf(1, "Unlimited stack, doing reexec\n");
446 // A reasonably large stack size. It is bigger than the usual 8Mb, because,
447 // well, the program could have been run with unlimited stack for a reason.
448 SetStackSizeLimitInBytes(32 * 1024 * 1024);
449 ReExec();
450 }
451
452 __msan_clear_on_return();
453 if (__msan_get_track_origins())
454 VPrintf(1, "msan_track_origins\n");
455 if (!InitShadow(__msan_get_track_origins())) {
456 Printf("FATAL: MemorySanitizer can not mmap the shadow memory.\n");
457 Printf("FATAL: Make sure to compile with -fPIE and to link with -pie.\n");
458 Printf("FATAL: Disabling ASLR is known to cause this error.\n");
459 Printf("FATAL: If running under GDB, try "
460 "'set disable-randomization off'.\n");
461 DumpProcessMap();
462 Die();
463 }
464
465 Symbolizer::GetOrInit()->AddHooks(EnterSymbolizer, ExitSymbolizer);
466
467 InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir);
468
469 MsanTSDInit(MsanTSDDtor);
470
471 MsanAllocatorInit();
472
473 MsanThread *main_thread = MsanThread::Create(nullptr, nullptr);
474 SetCurrentThread(main_thread);
475 main_thread->ThreadStart();
476
477 #if MSAN_CONTAINS_UBSAN
478 __ubsan::InitAsPlugin();
479 #endif
480
481 VPrintf(1, "MemorySanitizer init done\n");
482
483 msan_init_is_running = 0;
484 msan_inited = 1;
485 }
486
__msan_set_keep_going(int keep_going)487 void __msan_set_keep_going(int keep_going) {
488 flags()->halt_on_error = !keep_going;
489 }
490
__msan_set_expect_umr(int expect_umr)491 void __msan_set_expect_umr(int expect_umr) {
492 if (expect_umr) {
493 msan_expected_umr_found = 0;
494 } else if (!msan_expected_umr_found) {
495 GET_CALLER_PC_BP_SP;
496 (void)sp;
497 GET_FATAL_STACK_TRACE_PC_BP(pc, bp);
498 ReportExpectedUMRNotFound(&stack);
499 Die();
500 }
501 msan_expect_umr = expect_umr;
502 }
503
__msan_print_shadow(const void * x,uptr size)504 void __msan_print_shadow(const void *x, uptr size) {
505 if (!MEM_IS_APP(x)) {
506 Printf("Not a valid application address: %p\n", x);
507 return;
508 }
509
510 DescribeMemoryRange(x, size);
511 }
512
__msan_dump_shadow(const void * x,uptr size)513 void __msan_dump_shadow(const void *x, uptr size) {
514 if (!MEM_IS_APP(x)) {
515 Printf("Not a valid application address: %p\n", x);
516 return;
517 }
518
519 unsigned char *s = (unsigned char*)MEM_TO_SHADOW(x);
520 for (uptr i = 0; i < size; i++)
521 Printf("%x%x ", s[i] >> 4, s[i] & 0xf);
522 Printf("\n");
523 }
524
__msan_test_shadow(const void * x,uptr size)525 sptr __msan_test_shadow(const void *x, uptr size) {
526 if (!MEM_IS_APP(x)) return -1;
527 unsigned char *s = (unsigned char *)MEM_TO_SHADOW((uptr)x);
528 if (__sanitizer::mem_is_zero((const char *)s, size))
529 return -1;
530 // Slow path: loop through again to find the location.
531 for (uptr i = 0; i < size; ++i)
532 if (s[i])
533 return i;
534 return -1;
535 }
536
__msan_check_mem_is_initialized(const void * x,uptr size)537 void __msan_check_mem_is_initialized(const void *x, uptr size) {
538 if (!__msan::flags()->report_umrs) return;
539 sptr offset = __msan_test_shadow(x, size);
540 if (offset < 0)
541 return;
542
543 GET_CALLER_PC_BP_SP;
544 (void)sp;
545 ReportUMRInsideAddressRange(__func__, x, size, offset);
546 __msan::PrintWarningWithOrigin(pc, bp,
547 __msan_get_origin(((const char *)x) + offset));
548 if (__msan::flags()->halt_on_error) {
549 Printf("Exiting\n");
550 Die();
551 }
552 }
553
__msan_set_poison_in_malloc(int do_poison)554 int __msan_set_poison_in_malloc(int do_poison) {
555 int old = flags()->poison_in_malloc;
556 flags()->poison_in_malloc = do_poison;
557 return old;
558 }
559
__msan_has_dynamic_component()560 int __msan_has_dynamic_component() { return false; }
561
562 NOINLINE
__msan_clear_on_return()563 void __msan_clear_on_return() {
564 __msan_param_tls[0] = 0;
565 }
566
__msan_partial_poison(const void * data,void * shadow,uptr size)567 void __msan_partial_poison(const void* data, void* shadow, uptr size) {
568 internal_memcpy((void*)MEM_TO_SHADOW((uptr)data), shadow, size);
569 }
570
__msan_load_unpoisoned(const void * src,uptr size,void * dst)571 void __msan_load_unpoisoned(const void *src, uptr size, void *dst) {
572 internal_memcpy(dst, src, size);
573 __msan_unpoison(dst, size);
574 }
575
__msan_set_origin(const void * a,uptr size,u32 origin)576 void __msan_set_origin(const void *a, uptr size, u32 origin) {
577 if (__msan_get_track_origins()) SetOrigin(a, size, origin);
578 }
579
580 // 'descr' is created at compile time and contains '----' in the beginning.
581 // When we see descr for the first time we replace '----' with a uniq id
582 // and set the origin to (id | (31-th bit)).
__msan_set_alloca_origin(void * a,uptr size,char * descr)583 void __msan_set_alloca_origin(void *a, uptr size, char *descr) {
584 __msan_set_alloca_origin4(a, size, descr, 0);
585 }
586
__msan_set_alloca_origin4(void * a,uptr size,char * descr,uptr pc)587 void __msan_set_alloca_origin4(void *a, uptr size, char *descr, uptr pc) {
588 static const u32 dash = '-';
589 static const u32 first_timer =
590 dash + (dash << 8) + (dash << 16) + (dash << 24);
591 u32 *id_ptr = (u32*)descr;
592 bool print = false; // internal_strstr(descr + 4, "AllocaTOTest") != 0;
593 u32 id = *id_ptr;
594 if (id == first_timer) {
595 u32 idx = atomic_fetch_add(&NumStackOriginDescrs, 1, memory_order_relaxed);
596 CHECK_LT(idx, kNumStackOriginDescrs);
597 StackOriginDescr[idx] = descr + 4;
598 #if SANITIZER_PPC64V1
599 // On PowerPC64 ELFv1, the address of a function actually points to a
600 // three-doubleword data structure with the first field containing
601 // the address of the function's code.
602 if (pc)
603 pc = *reinterpret_cast<uptr*>(pc);
604 #endif
605 StackOriginPC[idx] = pc;
606 id = Origin::CreateStackOrigin(idx).raw_id();
607 *id_ptr = id;
608 if (print)
609 Printf("First time: idx=%d id=%d %s %p \n", idx, id, descr + 4, pc);
610 }
611 if (print)
612 Printf("__msan_set_alloca_origin: descr=%s id=%x\n", descr + 4, id);
613 __msan_set_origin(a, size, id);
614 }
615
__msan_chain_origin(u32 id)616 u32 __msan_chain_origin(u32 id) {
617 GET_CALLER_PC_BP_SP;
618 (void)sp;
619 GET_STORE_STACK_TRACE_PC_BP(pc, bp);
620 return ChainOrigin(id, &stack);
621 }
622
__msan_get_origin(const void * a)623 u32 __msan_get_origin(const void *a) {
624 if (!__msan_get_track_origins()) return 0;
625 uptr x = (uptr)a;
626 uptr aligned = x & ~3ULL;
627 uptr origin_ptr = MEM_TO_ORIGIN(aligned);
628 return *(u32*)origin_ptr;
629 }
630
__msan_origin_is_descendant_or_same(u32 this_id,u32 prev_id)631 int __msan_origin_is_descendant_or_same(u32 this_id, u32 prev_id) {
632 Origin o = Origin::FromRawId(this_id);
633 while (o.raw_id() != prev_id && o.isChainedOrigin())
634 o = o.getNextChainedOrigin(nullptr);
635 return o.raw_id() == prev_id;
636 }
637
__msan_get_umr_origin()638 u32 __msan_get_umr_origin() {
639 return __msan_origin_tls;
640 }
641
__sanitizer_unaligned_load16(const uu16 * p)642 u16 __sanitizer_unaligned_load16(const uu16 *p) {
643 internal_memcpy(&__msan_retval_tls[0], (void *)MEM_TO_SHADOW((uptr)p),
644 sizeof(uu16));
645 if (__msan_get_track_origins())
646 __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));
647 return *p;
648 }
__sanitizer_unaligned_load32(const uu32 * p)649 u32 __sanitizer_unaligned_load32(const uu32 *p) {
650 internal_memcpy(&__msan_retval_tls[0], (void *)MEM_TO_SHADOW((uptr)p),
651 sizeof(uu32));
652 if (__msan_get_track_origins())
653 __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));
654 return *p;
655 }
__sanitizer_unaligned_load64(const uu64 * p)656 u64 __sanitizer_unaligned_load64(const uu64 *p) {
657 internal_memcpy(&__msan_retval_tls[0], (void *)MEM_TO_SHADOW((uptr)p),
658 sizeof(uu64));
659 if (__msan_get_track_origins())
660 __msan_retval_origin_tls = GetOriginIfPoisoned((uptr)p, sizeof(*p));
661 return *p;
662 }
__sanitizer_unaligned_store16(uu16 * p,u16 x)663 void __sanitizer_unaligned_store16(uu16 *p, u16 x) {
664 static_assert(sizeof(uu16) == sizeof(u16), "incompatible types");
665 u16 s;
666 internal_memcpy(&s, &__msan_param_tls[1], sizeof(uu16));
667 internal_memcpy((void *)MEM_TO_SHADOW((uptr)p), &s, sizeof(uu16));
668 if (s && __msan_get_track_origins())
669 if (uu32 o = __msan_param_origin_tls[2])
670 SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);
671 *p = x;
672 }
__sanitizer_unaligned_store32(uu32 * p,u32 x)673 void __sanitizer_unaligned_store32(uu32 *p, u32 x) {
674 static_assert(sizeof(uu32) == sizeof(u32), "incompatible types");
675 u32 s;
676 internal_memcpy(&s, &__msan_param_tls[1], sizeof(uu32));
677 internal_memcpy((void *)MEM_TO_SHADOW((uptr)p), &s, sizeof(uu32));
678 if (s && __msan_get_track_origins())
679 if (uu32 o = __msan_param_origin_tls[2])
680 SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);
681 *p = x;
682 }
__sanitizer_unaligned_store64(uu64 * p,u64 x)683 void __sanitizer_unaligned_store64(uu64 *p, u64 x) {
684 u64 s = __msan_param_tls[1];
685 *(uu64 *)MEM_TO_SHADOW((uptr)p) = s;
686 if (s && __msan_get_track_origins())
687 if (uu32 o = __msan_param_origin_tls[2])
688 SetOriginIfPoisoned((uptr)p, (uptr)&s, sizeof(s), o);
689 *p = x;
690 }
691
__msan_set_death_callback(void (* callback)(void))692 void __msan_set_death_callback(void (*callback)(void)) {
693 SetUserDieCallback(callback);
694 }
695
__msan_start_switch_fiber(const void * bottom,uptr size)696 void __msan_start_switch_fiber(const void *bottom, uptr size) {
697 MsanThread *t = GetCurrentThread();
698 if (!t) {
699 VReport(1, "__msan_start_switch_fiber called from unknown thread\n");
700 return;
701 }
702 t->StartSwitchFiber((uptr)bottom, size);
703 }
704
__msan_finish_switch_fiber(const void ** bottom_old,uptr * size_old)705 void __msan_finish_switch_fiber(const void **bottom_old, uptr *size_old) {
706 MsanThread *t = GetCurrentThread();
707 if (!t) {
708 VReport(1, "__msan_finish_switch_fiber called from unknown thread\n");
709 return;
710 }
711 t->FinishSwitchFiber((uptr *)bottom_old, (uptr *)size_old);
712
713 internal_memset(__msan_param_tls, 0, sizeof(__msan_param_tls));
714 internal_memset(__msan_retval_tls, 0, sizeof(__msan_retval_tls));
715 internal_memset(__msan_va_arg_tls, 0, sizeof(__msan_va_arg_tls));
716
717 if (__msan_get_track_origins()) {
718 internal_memset(__msan_param_origin_tls, 0,
719 sizeof(__msan_param_origin_tls));
720 internal_memset(&__msan_retval_origin_tls, 0,
721 sizeof(__msan_retval_origin_tls));
722 internal_memset(__msan_va_arg_origin_tls, 0,
723 sizeof(__msan_va_arg_origin_tls));
724 }
725 }
726
SANITIZER_INTERFACE_WEAK_DEF(const char *,__msan_default_options,void)727 SANITIZER_INTERFACE_WEAK_DEF(const char *, __msan_default_options, void) {
728 return "";
729 }
730
731 extern "C" {
732 SANITIZER_INTERFACE_ATTRIBUTE
__sanitizer_print_stack_trace()733 void __sanitizer_print_stack_trace() {
734 GET_FATAL_STACK_TRACE_PC_BP(StackTrace::GetCurrentPc(), GET_CURRENT_FRAME());
735 stack.Print();
736 }
737 } // extern "C"
738