1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
|
//===- FuzzerTracePC.cpp - PC tracing--------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// Trace PCs.
// This module implements __sanitizer_cov_trace_pc_guard[_init],
// the callback required for -fsanitize-coverage=trace-pc-guard instrumentation.
//
//===----------------------------------------------------------------------===//
#include "FuzzerTracePC.h"
#include "FuzzerBuiltins.h"
#include "FuzzerBuiltinsMsvc.h"
#include "FuzzerCorpus.h"
#include "FuzzerDefs.h"
#include "FuzzerDictionary.h"
#include "FuzzerExtFunctions.h"
#include "FuzzerIO.h"
#include "FuzzerUtil.h"
#include "FuzzerValueBitMap.h"
#include <set>
// Used by -fsanitize-coverage=stack-depth to track stack depth
ATTRIBUTES_INTERFACE_TLS_INITIAL_EXEC uintptr_t __sancov_lowest_stack;
namespace fuzzer {
TracePC TPC;
size_t TracePC::GetTotalPCCoverage() {
return ObservedPCs.size();
}
void TracePC::HandleInline8bitCountersInit(uint8_t *Start, uint8_t *Stop) {
if (Start == Stop) return;
if (NumModules &&
Modules[NumModules - 1].Start() == Start)
return;
assert(NumModules <
sizeof(Modules) / sizeof(Modules[0]));
auto &M = Modules[NumModules++];
uint8_t *AlignedStart = RoundUpByPage(Start);
uint8_t *AlignedStop = RoundDownByPage(Stop);
size_t NumFullPages = AlignedStop > AlignedStart ?
(AlignedStop - AlignedStart) / PageSize() : 0;
bool NeedFirst = Start < AlignedStart || !NumFullPages;
bool NeedLast = Stop > AlignedStop && AlignedStop >= AlignedStart;
M.NumRegions = NumFullPages + NeedFirst + NeedLast;;
assert(M.NumRegions > 0);
M.Regions = new Module::Region[M.NumRegions];
assert(M.Regions);
size_t R = 0;
if (NeedFirst)
M.Regions[R++] = {Start, std::min(Stop, AlignedStart), true, false};
for (uint8_t *P = AlignedStart; P < AlignedStop; P += PageSize())
M.Regions[R++] = {P, P + PageSize(), true, true};
if (NeedLast)
M.Regions[R++] = {AlignedStop, Stop, true, false};
assert(R == M.NumRegions);
assert(M.Size() == (size_t)(Stop - Start));
assert(M.Stop() == Stop);
assert(M.Start() == Start);
NumInline8bitCounters += M.Size();
}
void TracePC::HandlePCsInit(const uintptr_t *Start, const uintptr_t *Stop) {
const PCTableEntry *B = reinterpret_cast<const PCTableEntry *>(Start);
const PCTableEntry *E = reinterpret_cast<const PCTableEntry *>(Stop);
if (NumPCTables && ModulePCTable[NumPCTables - 1].Start == B) return;
assert(NumPCTables < sizeof(ModulePCTable) / sizeof(ModulePCTable[0]));
ModulePCTable[NumPCTables++] = {B, E};
NumPCsInPCTables += E - B;
}
void TracePC::PrintModuleInfo() {
if (NumModules) {
Printf("INFO: Loaded %zd modules (%zd inline 8-bit counters): ",
NumModules, NumInline8bitCounters);
for (size_t i = 0; i < NumModules; i++)
Printf("%zd [%p, %p), ", Modules[i].Size(), Modules[i].Start(),
Modules[i].Stop());
Printf("\n");
}
if (NumPCTables) {
Printf("INFO: Loaded %zd PC tables (%zd PCs): ", NumPCTables,
NumPCsInPCTables);
for (size_t i = 0; i < NumPCTables; i++) {
Printf("%zd [%p,%p), ", ModulePCTable[i].Stop - ModulePCTable[i].Start,
ModulePCTable[i].Start, ModulePCTable[i].Stop);
}
Printf("\n");
if (NumInline8bitCounters && NumInline8bitCounters != NumPCsInPCTables) {
Printf("ERROR: The size of coverage PC tables does not match the\n"
"number of instrumented PCs. This might be a compiler bug,\n"
"please contact the libFuzzer developers.\n"
"Also check https://bugs.llvm.org/show_bug.cgi?id=34636\n"
"for possible workarounds (tl;dr: don't use the old GNU ld)\n");
_Exit(1);
}
}
if (size_t NumExtraCounters = ExtraCountersEnd() - ExtraCountersBegin())
Printf("INFO: %zd Extra Counters\n", NumExtraCounters);
}
ATTRIBUTE_NO_SANITIZE_ALL
void TracePC::HandleCallerCallee(uintptr_t Caller, uintptr_t Callee) {
const uintptr_t kBits = 12;
const uintptr_t kMask = (1 << kBits) - 1;
uintptr_t Idx = (Caller & kMask) | ((Callee & kMask) << kBits);
ValueProfileMap.AddValueModPrime(Idx);
}
/// \return the address of the previous instruction.
/// Note: the logic is copied from `sanitizer_common/sanitizer_stacktrace.h`
inline ALWAYS_INLINE uintptr_t GetPreviousInstructionPc(uintptr_t PC) {
#if defined(__arm__)
// T32 (Thumb) branch instructions might be 16 or 32 bit long,
// so we return (pc-2) in that case in order to be safe.
// For A32 mode we return (pc-4) because all instructions are 32 bit long.
return (PC - 3) & (~1);
#elif defined(__powerpc__) || defined(__powerpc64__) || defined(__aarch64__)
// PCs are always 4 byte aligned.
return PC - 4;
#elif defined(__sparc__) || defined(__mips__)
return PC - 8;
#else
return PC - 1;
#endif
}
/// \return the address of the next instruction.
/// Note: the logic is copied from `sanitizer_common/sanitizer_stacktrace.cpp`
ALWAYS_INLINE uintptr_t TracePC::GetNextInstructionPc(uintptr_t PC) {
#if defined(__mips__)
return PC + 8;
#elif defined(__powerpc__) || defined(__sparc__) || defined(__arm__) || \
defined(__aarch64__)
return PC + 4;
#else
return PC + 1;
#endif
}
void TracePC::UpdateObservedPCs() {
Vector<uintptr_t> CoveredFuncs;
auto ObservePC = [&](const PCTableEntry *TE) {
if (ObservedPCs.insert(TE).second && DoPrintNewPCs) {
PrintPC("\tNEW_PC: %p %F %L", "\tNEW_PC: %p",
GetNextInstructionPc(TE->PC));
Printf("\n");
}
};
auto Observe = [&](const PCTableEntry *TE) {
if (PcIsFuncEntry(TE))
if (++ObservedFuncs[TE->PC] == 1 && NumPrintNewFuncs)
CoveredFuncs.push_back(TE->PC);
ObservePC(TE);
};
if (NumPCsInPCTables) {
if (NumInline8bitCounters == NumPCsInPCTables) {
for (size_t i = 0; i < NumModules; i++) {
auto &M = Modules[i];
assert(M.Size() ==
(size_t)(ModulePCTable[i].Stop - ModulePCTable[i].Start));
for (size_t r = 0; r < M.NumRegions; r++) {
auto &R = M.Regions[r];
if (!R.Enabled) continue;
for (uint8_t *P = R.Start; P < R.Stop; P++)
if (*P)
Observe(&ModulePCTable[i].Start[M.Idx(P)]);
}
}
}
}
for (size_t i = 0, N = Min(CoveredFuncs.size(), NumPrintNewFuncs); i < N;
i++) {
Printf("\tNEW_FUNC[%zd/%zd]: ", i + 1, CoveredFuncs.size());
PrintPC("%p %F %L", "%p", GetNextInstructionPc(CoveredFuncs[i]));
Printf("\n");
}
}
uintptr_t TracePC::PCTableEntryIdx(const PCTableEntry *TE) {
size_t TotalTEs = 0;
for (size_t i = 0; i < NumPCTables; i++) {
auto &M = ModulePCTable[i];
if (TE >= M.Start && TE < M.Stop)
return TotalTEs + TE - M.Start;
TotalTEs += M.Stop - M.Start;
}
assert(0);
return 0;
}
const TracePC::PCTableEntry *TracePC::PCTableEntryByIdx(uintptr_t Idx) {
for (size_t i = 0; i < NumPCTables; i++) {
auto &M = ModulePCTable[i];
size_t Size = M.Stop - M.Start;
if (Idx < Size) return &M.Start[Idx];
Idx -= Size;
}
return nullptr;
}
static std::string GetModuleName(uintptr_t PC) {
char ModulePathRaw[4096] = ""; // What's PATH_MAX in portable C++?
void *OffsetRaw = nullptr;
if (!EF->__sanitizer_get_module_and_offset_for_pc(
reinterpret_cast<void *>(PC), ModulePathRaw,
sizeof(ModulePathRaw), &OffsetRaw))
return "";
return ModulePathRaw;
}
template<class CallBack>
void TracePC::IterateCoveredFunctions(CallBack CB) {
for (size_t i = 0; i < NumPCTables; i++) {
auto &M = ModulePCTable[i];
assert(M.Start < M.Stop);
auto ModuleName = GetModuleName(M.Start->PC);
for (auto NextFE = M.Start; NextFE < M.Stop; ) {
auto FE = NextFE;
assert(PcIsFuncEntry(FE) && "Not a function entry point");
do {
NextFE++;
} while (NextFE < M.Stop && !(PcIsFuncEntry(NextFE)));
CB(FE, NextFE, ObservedFuncs[FE->PC]);
}
}
}
void TracePC::SetFocusFunction(const std::string &FuncName) {
// This function should be called once.
assert(!FocusFunctionCounterPtr);
if (FuncName.empty())
return;
for (size_t M = 0; M < NumModules; M++) {
auto &PCTE = ModulePCTable[M];
size_t N = PCTE.Stop - PCTE.Start;
for (size_t I = 0; I < N; I++) {
if (!(PcIsFuncEntry(&PCTE.Start[I]))) continue; // not a function entry.
auto Name = DescribePC("%F", GetNextInstructionPc(PCTE.Start[I].PC));
if (Name[0] == 'i' && Name[1] == 'n' && Name[2] == ' ')
Name = Name.substr(3, std::string::npos);
if (FuncName != Name) continue;
Printf("INFO: Focus function is set to '%s'\n", Name.c_str());
FocusFunctionCounterPtr = Modules[M].Start() + I;
return;
}
}
}
bool TracePC::ObservedFocusFunction() {
return FocusFunctionCounterPtr && *FocusFunctionCounterPtr;
}
void TracePC::PrintCoverage() {
if (!EF->__sanitizer_symbolize_pc ||
!EF->__sanitizer_get_module_and_offset_for_pc) {
Printf("INFO: __sanitizer_symbolize_pc or "
"__sanitizer_get_module_and_offset_for_pc is not available,"
" not printing coverage\n");
return;
}
Printf("COVERAGE:\n");
auto CoveredFunctionCallback = [&](const PCTableEntry *First,
const PCTableEntry *Last,
uintptr_t Counter) {
assert(First < Last);
auto VisualizePC = GetNextInstructionPc(First->PC);
std::string FileStr = DescribePC("%s", VisualizePC);
if (!IsInterestingCoverageFile(FileStr))
return;
std::string FunctionStr = DescribePC("%F", VisualizePC);
if (FunctionStr.find("in ") == 0)
FunctionStr = FunctionStr.substr(3);
std::string LineStr = DescribePC("%l", VisualizePC);
size_t NumEdges = Last - First;
Vector<uintptr_t> UncoveredPCs;
for (auto TE = First; TE < Last; TE++)
if (!ObservedPCs.count(TE))
UncoveredPCs.push_back(TE->PC);
Printf("%sCOVERED_FUNC: hits: %zd", Counter ? "" : "UN", Counter);
Printf(" edges: %zd/%zd", NumEdges - UncoveredPCs.size(), NumEdges);
Printf(" %s %s:%s\n", FunctionStr.c_str(), FileStr.c_str(),
LineStr.c_str());
if (Counter)
for (auto PC : UncoveredPCs)
Printf(" UNCOVERED_PC: %s\n",
DescribePC("%s:%l", GetNextInstructionPc(PC)).c_str());
};
IterateCoveredFunctions(CoveredFunctionCallback);
}
// Value profile.
// We keep track of various values that affect control flow.
// These values are inserted into a bit-set-based hash map.
// Every new bit in the map is treated as a new coverage.
//
// For memcmp/strcmp/etc the interesting value is the length of the common
// prefix of the parameters.
// For cmp instructions the interesting value is a XOR of the parameters.
// The interesting value is mixed up with the PC and is then added to the map.
ATTRIBUTE_NO_SANITIZE_ALL
void TracePC::AddValueForMemcmp(void *caller_pc, const void *s1, const void *s2,
size_t n, bool StopAtZero) {
if (!n) return;
size_t Len = std::min(n, Word::GetMaxSize());
const uint8_t *A1 = reinterpret_cast<const uint8_t *>(s1);
const uint8_t *A2 = reinterpret_cast<const uint8_t *>(s2);
uint8_t B1[Word::kMaxSize];
uint8_t B2[Word::kMaxSize];
// Copy the data into locals in this non-msan-instrumented function
// to avoid msan complaining further.
size_t Hash = 0; // Compute some simple hash of both strings.
for (size_t i = 0; i < Len; i++) {
B1[i] = A1[i];
B2[i] = A2[i];
size_t T = B1[i];
Hash ^= (T << 8) | B2[i];
}
size_t I = 0;
uint8_t HammingDistance = 0;
for (; I < Len; I++) {
if (B1[I] != B2[I] || (StopAtZero && B1[I] == 0)) {
HammingDistance = Popcountll(B1[I] ^ B2[I]);
break;
}
}
size_t PC = reinterpret_cast<size_t>(caller_pc);
size_t Idx = (PC & 4095) | (I << 12);
Idx += HammingDistance;
ValueProfileMap.AddValue(Idx);
TORCW.Insert(Idx ^ Hash, Word(B1, Len), Word(B2, Len));
}
template <class T>
ATTRIBUTE_TARGET_POPCNT ALWAYS_INLINE
ATTRIBUTE_NO_SANITIZE_ALL
void TracePC::HandleCmp(uintptr_t PC, T Arg1, T Arg2) {
uint64_t ArgXor = Arg1 ^ Arg2;
if (sizeof(T) == 4)
TORC4.Insert(ArgXor, Arg1, Arg2);
else if (sizeof(T) == 8)
TORC8.Insert(ArgXor, Arg1, Arg2);
uint64_t HammingDistance = Popcountll(ArgXor); // [0,64]
uint64_t AbsoluteDistance = (Arg1 == Arg2 ? 0 : Clzll(Arg1 - Arg2) + 1);
ValueProfileMap.AddValue(PC * 128 + HammingDistance);
ValueProfileMap.AddValue(PC * 128 + 64 + AbsoluteDistance);
}
static size_t InternalStrnlen(const char *S, size_t MaxLen) {
size_t Len = 0;
for (; Len < MaxLen && S[Len]; Len++) {}
return Len;
}
// Finds min of (strlen(S1), strlen(S2)).
// Needed bacause one of these strings may actually be non-zero terminated.
static size_t InternalStrnlen2(const char *S1, const char *S2) {
size_t Len = 0;
for (; S1[Len] && S2[Len]; Len++) {}
return Len;
}
void TracePC::ClearInlineCounters() {
IterateCounterRegions([](const Module::Region &R){
if (R.Enabled)
memset(R.Start, 0, R.Stop - R.Start);
});
}
ATTRIBUTE_NO_SANITIZE_ALL
void TracePC::RecordInitialStack() {
int stack;
__sancov_lowest_stack = InitialStack = reinterpret_cast<uintptr_t>(&stack);
}
uintptr_t TracePC::GetMaxStackOffset() const {
return InitialStack - __sancov_lowest_stack; // Stack grows down
}
void WarnAboutDeprecatedInstrumentation(const char *flag) {
// Use RawPrint because Printf cannot be used on Windows before OutputFile is
// initialized.
RawPrint(flag);
RawPrint(
" is no longer supported by libFuzzer.\n"
"Please either migrate to a compiler that supports -fsanitize=fuzzer\n"
"or use an older version of libFuzzer\n");
exit(1);
}
} // namespace fuzzer
extern "C" {
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
void __sanitizer_cov_trace_pc_guard(uint32_t *Guard) {
fuzzer::WarnAboutDeprecatedInstrumentation(
"-fsanitize-coverage=trace-pc-guard");
}
// Best-effort support for -fsanitize-coverage=trace-pc, which is available
// in both Clang and GCC.
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
void __sanitizer_cov_trace_pc() {
fuzzer::WarnAboutDeprecatedInstrumentation("-fsanitize-coverage=trace-pc");
}
ATTRIBUTE_INTERFACE
void __sanitizer_cov_trace_pc_guard_init(uint32_t *Start, uint32_t *Stop) {
fuzzer::WarnAboutDeprecatedInstrumentation(
"-fsanitize-coverage=trace-pc-guard");
}
ATTRIBUTE_INTERFACE
void __sanitizer_cov_8bit_counters_init(uint8_t *Start, uint8_t *Stop) {
fuzzer::TPC.HandleInline8bitCountersInit(Start, Stop);
}
ATTRIBUTE_INTERFACE
void __sanitizer_cov_pcs_init(const uintptr_t *pcs_beg,
const uintptr_t *pcs_end) {
fuzzer::TPC.HandlePCsInit(pcs_beg, pcs_end);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
void __sanitizer_cov_trace_pc_indir(uintptr_t Callee) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCallerCallee(PC, Callee);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_cmp8(uint64_t Arg1, uint64_t Arg2) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
// Now the __sanitizer_cov_trace_const_cmp[1248] callbacks just mimic
// the behaviour of __sanitizer_cov_trace_cmp[1248] ones. This, however,
// should be changed later to make full use of instrumentation.
void __sanitizer_cov_trace_const_cmp8(uint64_t Arg1, uint64_t Arg2) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_cmp4(uint32_t Arg1, uint32_t Arg2) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_const_cmp4(uint32_t Arg1, uint32_t Arg2) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_cmp2(uint16_t Arg1, uint16_t Arg2) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_const_cmp2(uint16_t Arg1, uint16_t Arg2) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_cmp1(uint8_t Arg1, uint8_t Arg2) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_const_cmp1(uint8_t Arg1, uint8_t Arg2) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Arg1, Arg2);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_switch(uint64_t Val, uint64_t *Cases) {
uint64_t N = Cases[0];
uint64_t ValSizeInBits = Cases[1];
uint64_t *Vals = Cases + 2;
// Skip the most common and the most boring case: all switch values are small.
// We may want to skip this at compile-time, but it will make the
// instrumentation less general.
if (Vals[N - 1] < 256)
return;
// Also skip small inputs values, they won't give good signal.
if (Val < 256)
return;
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
size_t i;
uint64_t Smaller = 0;
uint64_t Larger = ~(uint64_t)0;
// Find two switch values such that Smaller < Val < Larger.
// Use 0 and 0xfff..f as the defaults.
for (i = 0; i < N; i++) {
if (Val < Vals[i]) {
Larger = Vals[i];
break;
}
if (Val > Vals[i]) Smaller = Vals[i];
}
// Apply HandleCmp to {Val,Smaller} and {Val, Larger},
// use i as the PC modifier for HandleCmp.
if (ValSizeInBits == 16) {
fuzzer::TPC.HandleCmp(PC + 2 * i, static_cast<uint16_t>(Val),
(uint16_t)(Smaller));
fuzzer::TPC.HandleCmp(PC + 2 * i + 1, static_cast<uint16_t>(Val),
(uint16_t)(Larger));
} else if (ValSizeInBits == 32) {
fuzzer::TPC.HandleCmp(PC + 2 * i, static_cast<uint32_t>(Val),
(uint32_t)(Smaller));
fuzzer::TPC.HandleCmp(PC + 2 * i + 1, static_cast<uint32_t>(Val),
(uint32_t)(Larger));
} else {
fuzzer::TPC.HandleCmp(PC + 2*i, Val, Smaller);
fuzzer::TPC.HandleCmp(PC + 2*i + 1, Val, Larger);
}
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_div4(uint32_t Val) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Val, (uint32_t)0);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_div8(uint64_t Val) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Val, (uint64_t)0);
}
ATTRIBUTE_INTERFACE
ATTRIBUTE_NO_SANITIZE_ALL
ATTRIBUTE_TARGET_POPCNT
void __sanitizer_cov_trace_gep(uintptr_t Idx) {
uintptr_t PC = reinterpret_cast<uintptr_t>(GET_CALLER_PC());
fuzzer::TPC.HandleCmp(PC, Idx, (uintptr_t)0);
}
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
void __sanitizer_weak_hook_memcmp(void *caller_pc, const void *s1,
const void *s2, size_t n, int result) {
if (!fuzzer::RunningUserCallback) return;
if (result == 0) return; // No reason to mutate.
if (n <= 1) return; // Not interesting.
fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, n, /*StopAtZero*/false);
}
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
void __sanitizer_weak_hook_strncmp(void *caller_pc, const char *s1,
const char *s2, size_t n, int result) {
if (!fuzzer::RunningUserCallback) return;
if (result == 0) return; // No reason to mutate.
size_t Len1 = fuzzer::InternalStrnlen(s1, n);
size_t Len2 = fuzzer::InternalStrnlen(s2, n);
n = std::min(n, Len1);
n = std::min(n, Len2);
if (n <= 1) return; // Not interesting.
fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, n, /*StopAtZero*/true);
}
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
void __sanitizer_weak_hook_strcmp(void *caller_pc, const char *s1,
const char *s2, int result) {
if (!fuzzer::RunningUserCallback) return;
if (result == 0) return; // No reason to mutate.
size_t N = fuzzer::InternalStrnlen2(s1, s2);
if (N <= 1) return; // Not interesting.
fuzzer::TPC.AddValueForMemcmp(caller_pc, s1, s2, N, /*StopAtZero*/true);
}
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
void __sanitizer_weak_hook_strncasecmp(void *called_pc, const char *s1,
const char *s2, size_t n, int result) {
if (!fuzzer::RunningUserCallback) return;
return __sanitizer_weak_hook_strncmp(called_pc, s1, s2, n, result);
}
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
void __sanitizer_weak_hook_strcasecmp(void *called_pc, const char *s1,
const char *s2, int result) {
if (!fuzzer::RunningUserCallback) return;
return __sanitizer_weak_hook_strcmp(called_pc, s1, s2, result);
}
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
void __sanitizer_weak_hook_strstr(void *called_pc, const char *s1,
const char *s2, char *result) {
if (!fuzzer::RunningUserCallback) return;
fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), strlen(s2));
}
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
void __sanitizer_weak_hook_strcasestr(void *called_pc, const char *s1,
const char *s2, char *result) {
if (!fuzzer::RunningUserCallback) return;
fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), strlen(s2));
}
ATTRIBUTE_INTERFACE ATTRIBUTE_NO_SANITIZE_MEMORY
void __sanitizer_weak_hook_memmem(void *called_pc, const void *s1, size_t len1,
const void *s2, size_t len2, void *result) {
if (!fuzzer::RunningUserCallback) return;
fuzzer::TPC.MMT.Add(reinterpret_cast<const uint8_t *>(s2), len2);
}
} // extern "C"
|