[llvm] r257245 - [libFuzzer] don't limit memcmp tracing with 8 bytes
Kostya Serebryany via llvm-commits
llvm-commits at lists.llvm.org
Fri Jan 8 17:39:56 PST 2016
Author: kcc
Date: Fri Jan 8 19:39:55 2016
New Revision: 257245
URL: http://llvm.org/viewvc/llvm-project?rev=257245&view=rev
Log:
[libFuzzer] don't limit memcmp tracing with 8 bytes
Modified:
llvm/trunk/lib/Fuzzer/FuzzerTraceState.cpp
llvm/trunk/lib/Fuzzer/test/MemcmpTest.cpp
llvm/trunk/lib/Fuzzer/test/fuzzer-dfsan.test
Modified: llvm/trunk/lib/Fuzzer/FuzzerTraceState.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/FuzzerTraceState.cpp?rev=257245&r1=257244&r2=257245&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/FuzzerTraceState.cpp (original)
+++ llvm/trunk/lib/Fuzzer/FuzzerTraceState.cpp Fri Jan 8 19:39:55 2016
@@ -172,6 +172,8 @@ struct TraceBasedMutation {
uint8_t Data[kMaxSize];
};
+const size_t TraceBasedMutation::kMaxSize;
+
class TraceState {
public:
TraceState(const Fuzzer::FuzzingOptions &Options, const Unit &CurrentUnit)
@@ -186,15 +188,22 @@ class TraceState {
void DFSanCmpCallback(uintptr_t PC, size_t CmpSize, size_t CmpType,
uint64_t Arg1, uint64_t Arg2, dfsan_label L1,
dfsan_label L2);
+ void DFSanMemcmpCallback(size_t CmpSize, const uint8_t *Data1,
+ const uint8_t *Data2, dfsan_label L1,
+ dfsan_label L2);
void DFSanSwitchCallback(uint64_t PC, size_t ValSizeInBits, uint64_t Val,
size_t NumCases, uint64_t *Cases, dfsan_label L);
void TraceCmpCallback(uintptr_t PC, size_t CmpSize, size_t CmpType,
uint64_t Arg1, uint64_t Arg2);
+ void TraceMemcmpCallback(size_t CmpSize, const uint8_t *Data1,
+ const uint8_t *Data2);
void TraceSwitchCallback(uintptr_t PC, size_t ValSizeInBits, uint64_t Val,
size_t NumCases, uint64_t *Cases);
int TryToAddDesiredData(uint64_t PresentData, uint64_t DesiredData,
size_t DataSize);
+ int TryToAddDesiredData(const uint8_t *PresentData,
+ const uint8_t *DesiredData, size_t DataSize);
void StartTraceRecording() {
if (!Options.UseTraces) return;
@@ -209,12 +218,18 @@ class TraceState {
void ApplyTraceBasedMutation(size_t Idx, fuzzer::Unit *U);
- void AddMutation(uint32_t Pos, uint32_t Size, uint64_t Data) {
+ void AddMutation(uint32_t Pos, uint32_t Size, const uint8_t *Data) {
if (NumMutations >= kMaxMutations) return;
+ assert(Size <= TraceBasedMutation::kMaxSize);
auto &M = Mutations[NumMutations++];
M.Pos = Pos;
M.Size = Size;
- memcpy(M.Data, &Data, sizeof(Data));
+ memcpy(M.Data, Data, Size);
+ }
+
+ void AddMutation(uint32_t Pos, uint32_t Size, uint64_t Data) {
+ assert(Size <= sizeof(Data));
+ AddMutation(Pos, Size, reinterpret_cast<uint8_t*>(&Data));
}
private:
@@ -287,6 +302,26 @@ void TraceState::DFSanCmpCallback(uintpt
PC, CmpSize, CmpType, Arg1, Arg2, Res, L1, L2, NumMutations);
}
+void TraceState::DFSanMemcmpCallback(size_t CmpSize, const uint8_t *Data1,
+ const uint8_t *Data2, dfsan_label L1,
+ dfsan_label L2) {
+
+ assert(ReallyHaveDFSan());
+ if (!RecordingTraces || !IsMyThread) return;
+ if (L1 == 0 && L2 == 0)
+ return; // Not actionable.
+ if (L1 != 0 && L2 != 0)
+ return; // Probably still actionable.
+
+ const uint8_t *Data = L1 ? Data2 : Data1;
+ LabelRange LR = L1 ? GetLabelRange(L1) : GetLabelRange(L2);
+ for (size_t Pos = LR.Beg; Pos + CmpSize <= LR.End; Pos++) {
+ AddMutation(Pos, CmpSize, Data);
+ if (Options.Verbosity >= 3)
+ Printf("DFSanMemcmpCallback: Pos %d Size %d\n", Pos, CmpSize);
+ }
+}
+
void TraceState::DFSanSwitchCallback(uint64_t PC, size_t ValSizeInBits,
uint64_t Val, size_t NumCases,
uint64_t *Cases, dfsan_label L) {
@@ -333,6 +368,24 @@ int TraceState::TryToAddDesiredData(uint
return Res;
}
+int TraceState::TryToAddDesiredData(const uint8_t *PresentData,
+ const uint8_t *DesiredData,
+ size_t DataSize) {
+ int Res = 0;
+ const uint8_t *Beg = CurrentUnit.data();
+ const uint8_t *End = Beg + CurrentUnit.size();
+ for (const uint8_t *Cur = Beg; Cur < End; Cur++) {
+ Cur = (uint8_t *)memmem(Cur, End - Cur, PresentData, DataSize);
+ if (!Cur)
+ break;
+ size_t Pos = Cur - Beg;
+ assert(Pos < CurrentUnit.size());
+ AddMutation(Pos, DataSize, DesiredData);
+ Res++;
+ }
+ return Res;
+}
+
void TraceState::TraceCmpCallback(uintptr_t PC, size_t CmpSize, size_t CmpType,
uint64_t Arg1, uint64_t Arg2) {
if (!RecordingTraces || !IsMyThread) return;
@@ -347,6 +400,14 @@ void TraceState::TraceCmpCallback(uintpt
}
}
+void TraceState::TraceMemcmpCallback(size_t CmpSize, const uint8_t *Data1,
+ const uint8_t *Data2) {
+ if (!RecordingTraces || !IsMyThread) return;
+ CmpSize = std::min(CmpSize, TraceBasedMutation::kMaxSize);
+ TryToAddDesiredData(Data1, Data2, CmpSize);
+ TryToAddDesiredData(Data2, Data1, CmpSize);
+}
+
void TraceState::TraceSwitchCallback(uintptr_t PC, size_t ValSizeInBits,
uint64_t Val, size_t NumCases,
uint64_t *Cases) {
@@ -436,89 +497,66 @@ void dfsan_weak_hook_memcmp(void *caller
size_t n, dfsan_label s1_label,
dfsan_label s2_label, dfsan_label n_label) {
if (!TS) return;
- uintptr_t PC = reinterpret_cast<uintptr_t>(caller_pc);
- uint64_t S1 = 0, S2 = 0;
- // Simplification: handle only first 8 bytes.
- memcpy(&S1, s1, std::min(n, sizeof(S1)));
- memcpy(&S2, s2, std::min(n, sizeof(S2)));
dfsan_label L1 = dfsan_read_label(s1, n);
dfsan_label L2 = dfsan_read_label(s2, n);
- TS->DFSanCmpCallback(PC, n, fuzzer::ICMP_EQ, S1, S2, L1, L2);
+ TS->DFSanMemcmpCallback(n, reinterpret_cast<const uint8_t *>(s1),
+ reinterpret_cast<const uint8_t *>(s2), L1, L2);
}
void dfsan_weak_hook_strncmp(void *caller_pc, const char *s1, const char *s2,
size_t n, dfsan_label s1_label,
dfsan_label s2_label, dfsan_label n_label) {
if (!TS) return;
- uintptr_t PC = reinterpret_cast<uintptr_t>(caller_pc);
- uint64_t S1 = 0, S2 = 0;
n = std::min(n, fuzzer::InternalStrnlen(s1, n));
n = std::min(n, fuzzer::InternalStrnlen(s2, n));
- // Simplification: handle only first 8 bytes.
- memcpy(&S1, s1, std::min(n, sizeof(S1)));
- memcpy(&S2, s2, std::min(n, sizeof(S2)));
dfsan_label L1 = dfsan_read_label(s1, n);
dfsan_label L2 = dfsan_read_label(s2, n);
- TS->DFSanCmpCallback(PC, n, fuzzer::ICMP_EQ, S1, S2, L1, L2);
+ TS->DFSanMemcmpCallback(n, reinterpret_cast<const uint8_t *>(s1),
+ reinterpret_cast<const uint8_t *>(s2), L1, L2);
}
void dfsan_weak_hook_strcmp(void *caller_pc, const char *s1, const char *s2,
dfsan_label s1_label, dfsan_label s2_label) {
if (!TS) return;
- uintptr_t PC = reinterpret_cast<uintptr_t>(caller_pc);
- uint64_t S1 = 0, S2 = 0;
size_t Len1 = strlen(s1);
size_t Len2 = strlen(s2);
size_t N = std::min(Len1, Len2);
if (N <= 1) return; // Not interesting.
- // Simplification: handle only first 8 bytes.
- memcpy(&S1, s1, std::min(N, sizeof(S1)));
- memcpy(&S2, s2, std::min(N, sizeof(S2)));
dfsan_label L1 = dfsan_read_label(s1, Len1);
dfsan_label L2 = dfsan_read_label(s2, Len2);
- TS->DFSanCmpCallback(PC, N, fuzzer::ICMP_EQ, S1, S2, L1, L2);
+ TS->DFSanMemcmpCallback(N, reinterpret_cast<const uint8_t *>(s1),
+ reinterpret_cast<const uint8_t *>(s2), L1, L2);
}
void __sanitizer_weak_hook_memcmp(void *caller_pc, const void *s1,
const void *s2, size_t n) {
if (!TS) return;
- uintptr_t PC = reinterpret_cast<uintptr_t>(caller_pc);
- uint64_t S1 = 0, S2 = 0;
- // Simplification: handle only first 8 bytes.
- memcpy(&S1, s1, std::min(n, sizeof(S1)));
- memcpy(&S2, s2, std::min(n, sizeof(S2)));
- TS->TraceCmpCallback(PC, n, fuzzer::ICMP_EQ, S1, S2);
+ if (n <= 1) return; // Not interesting.
+ TS->TraceMemcmpCallback(n, reinterpret_cast<const uint8_t *>(s1),
+ reinterpret_cast<const uint8_t *>(s2));
}
void __sanitizer_weak_hook_strncmp(void *caller_pc, const char *s1,
const char *s2, size_t n) {
if (!TS) return;
- uintptr_t PC = reinterpret_cast<uintptr_t>(caller_pc);
- uint64_t S1 = 0, S2 = 0;
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.
- // Simplification: handle only first 8 bytes.
- memcpy(&S1, s1, std::min(n, sizeof(S1)));
- memcpy(&S2, s2, std::min(n, sizeof(S2)));
- TS->TraceCmpCallback(PC, n, fuzzer::ICMP_EQ, S1, S2);
+ TS->TraceMemcmpCallback(n, reinterpret_cast<const uint8_t *>(s1),
+ reinterpret_cast<const uint8_t *>(s2));
}
void __sanitizer_weak_hook_strcmp(void *caller_pc, const char *s1,
const char *s2) {
if (!TS) return;
- uintptr_t PC = reinterpret_cast<uintptr_t>(caller_pc);
- uint64_t S1 = 0, S2 = 0;
size_t Len1 = strlen(s1);
size_t Len2 = strlen(s2);
size_t N = std::min(Len1, Len2);
if (N <= 1) return; // Not interesting.
- // Simplification: handle only first 8 bytes.
- memcpy(&S1, s1, std::min(N, sizeof(S1)));
- memcpy(&S2, s2, std::min(N, sizeof(S2)));
- TS->TraceCmpCallback(PC, N, fuzzer::ICMP_EQ, S1, S2);
+ TS->TraceMemcmpCallback(N, reinterpret_cast<const uint8_t *>(s1),
+ reinterpret_cast<const uint8_t *>(s2));
}
__attribute__((visibility("default")))
Modified: llvm/trunk/lib/Fuzzer/test/MemcmpTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/test/MemcmpTest.cpp?rev=257245&r1=257244&r2=257245&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/test/MemcmpTest.cpp (original)
+++ llvm/trunk/lib/Fuzzer/test/MemcmpTest.cpp Fri Jan 8 19:39:55 2016
@@ -10,8 +10,16 @@ extern "C" int LLVMFuzzerTestOneInput(co
if (Size >= 12 && memcmp(Data + 8, "ABCD", 4) == 0) {
if (Size >= 14 && memcmp(Data + 12, "XY", 2) == 0) {
if (Size >= 16 && memcmp(Data + 14, "KLM", 3) == 0) {
- fprintf(stderr, "BINGO\n");
- exit(1);
+ if (Size >= 27 && memcmp(Data + 17, "ABCDE-GHIJ", 10) == 0){
+ fprintf(stderr, "BINGO %zd\n", Size);
+ for (size_t i = 0; i < Size; i++) {
+ uint8_t C = Data[i];
+ if (C >= 32 && C < 127)
+ fprintf(stderr, "%c", C);
+ }
+ fprintf(stderr, "\n");
+ exit(1);
+ }
}
}
}
Modified: llvm/trunk/lib/Fuzzer/test/fuzzer-dfsan.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Fuzzer/test/fuzzer-dfsan.test?rev=257245&r1=257244&r2=257245&view=diff
==============================================================================
--- llvm/trunk/lib/Fuzzer/test/fuzzer-dfsan.test (original)
+++ llvm/trunk/lib/Fuzzer/test/fuzzer-dfsan.test Fri Jan 8 19:39:55 2016
@@ -5,18 +5,19 @@ CHECK4: BINGO
CHECK_DFSanCmpCallback: DFSanCmpCallback: PC
CHECK_DFSanSwitchCallback: DFSanSwitchCallback: PC
+CHECK_DFSanMemcmpCallback: DFSanMemcmpCallback: Pos
RUN: not LLVMFuzzer-SimpleCmpTest-DFSan -use_traces=1 -seed=1 -runs=1000000 -timeout=5 2>&1 | FileCheck %s --check-prefix=CHECK1
RUN: LLVMFuzzer-SimpleCmpTest-DFSan -use_traces=1 -seed=1 -runs=100 -timeout=5 -verbosity=3 2>&1 | FileCheck %s -check-prefix=CHECK_DFSanCmpCallback
RUN: not LLVMFuzzer-MemcmpTest-DFSan -use_traces=1 -seed=1 -runs=10000 -timeout=5 2>&1 | FileCheck %s --check-prefix=CHECK2
-RUN: LLVMFuzzer-MemcmpTest-DFSan -use_traces=1 -seed=1 -runs=2 -timeout=5 -verbosity=3 2>&1 | FileCheck %s -check-prefix=CHECK_DFSanCmpCallback
+RUN: LLVMFuzzer-MemcmpTest-DFSan -use_traces=1 -seed=1 -runs=2 -timeout=5 -verbosity=3 2>&1 | FileCheck %s -check-prefix=CHECK_DFSanMemcmpCallback
RUN: not LLVMFuzzer-StrncmpTest-DFSan -use_traces=1 -seed=1 -runs=10000 -timeout=5 2>&1 | FileCheck %s --check-prefix=CHECK3
-RUN: LLVMFuzzer-StrncmpTest-DFSan -use_traces=1 -seed=1 -runs=2 -timeout=5 -verbosity=3 2>&1 | FileCheck %s -check-prefix=CHECK_DFSanCmpCallback
+RUN: LLVMFuzzer-StrncmpTest-DFSan -use_traces=1 -seed=1 -runs=2 -timeout=5 -verbosity=3 2>&1 | FileCheck %s -check-prefix=CHECK_DFSanMemcmpCallback
RUN: not LLVMFuzzer-StrcmpTest-DFSan -use_traces=1 -seed=1 -runs=10000 -timeout=5 2>&1 | FileCheck %s --check-prefix=CHECK3
-RUN: LLVMFuzzer-StrcmpTest-DFSan -use_traces=1 -seed=1 -runs=2 -timeout=5 -verbosity=3 2>&1 | FileCheck %s -check-prefix=CHECK_DFSanCmpCallback
+RUN: LLVMFuzzer-StrcmpTest-DFSan -use_traces=1 -seed=1 -runs=2 -timeout=5 -verbosity=3 2>&1 | FileCheck %s -check-prefix=CHECK_DFSanMemcmpCallback
RUN: not LLVMFuzzer-SwitchTest-DFSan -use_traces=1 -seed=1 -runs=100000 -timeout=5 2>&1 | FileCheck %s --check-prefix=CHECK4
RUN: LLVMFuzzer-SwitchTest-DFSan -use_traces=1 -seed=1 -runs=2 -timeout=5 -verbosity=3 2>&1 | FileCheck %s -check-prefix=CHECK_DFSanSwitchCallback
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