commit c6ee87514896e8845ed60aaac5cf5b7126b72d50
author morehouse <morehouse> Tue Jul 17 16:12:00 2018 +0000
committer morehouse <morehouse> Tue Jul 17 16:12:00 2018 +0000
tree 59a1a9753c0cd36f938975f42e08547b8fe285c9
parent 3f75cb411dde88b14e293d1b5fb9d42d1d184c01

libFuzzer: prevent irrelevant strings from leaking into auto-dictionary

This is a fix for bug 37047.

https://bugs.llvm.org/show_bug.cgi?id=37047

Implemented by basically reversing the logic. Previously all strings
were considered, with some operations excluded. Now strings are excluded
by default, and only strings during the CB considered.

Patch By: pdknsk

Differential Revision: https://reviews.llvm.org/D48800

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/fuzzer@337296 91177308-0d34-0410-b5e6-96231b3b80d8

FuzzerLoop.cpp

diff --git a/FuzzerLoop.cpp b/FuzzerLoop.cpp
index ba61c15..a2d53ee 100644
--- a/FuzzerLoop.cpp
+++ b/FuzzerLoop.cpp
@@ -43,6 +43,8 @@
 
 SharedMemoryRegion SMR;
 
+bool RunningUserCallback = false;
+
 // Only one Fuzzer per process.
 static Fuzzer *F;
 
@@ -243,7 +245,7 @@
 }
 
 void Fuzzer::ExitCallback() {
-  if (!RunningCB)
+  if (!RunningUserCallback)
     return; // This exit did not come from the user callback
   if (EF->__sanitizer_acquire_crash_state &&
       !EF->__sanitizer_acquire_crash_state())
@@ -277,7 +279,7 @@
   if (!InFuzzingThread())
     return;
 #endif
-  if (!RunningCB)
+  if (!RunningUserCallback)
     return; // We have not started running units yet.
   size_t Seconds =
       duration_cast<seconds>(system_clock::now() - UnitStartTime).count();
@@ -451,9 +453,9 @@
     ScopedEnableMsanInterceptorChecks S;
     UnitStartTime = system_clock::now();
     TPC.ResetMaps();
-    RunningCB = true;
+    RunningUserCallback = true;
     CB(Data, Size);
-    RunningCB = false;
+    RunningUserCallback = false;
     UnitStopTime = system_clock::now();
   };
 
@@ -558,9 +560,9 @@
     AllocTracer.Start(Options.TraceMalloc);
     UnitStartTime = system_clock::now();
     TPC.ResetMaps();
-    RunningCB = true;
+    RunningUserCallback = true;
     int Res = CB(DataCopy, Size);
-    RunningCB = false;
+    RunningUserCallback = false;
     UnitStopTime = system_clock::now();
     (void)Res;
     assert(Res == 0);