wasm support

Author: vanhauser-thc

GNUmakefile

@@ -388,6 +388,7 @@ help:
 	@echo NO_NYX - disable building nyx mode dependencies
 	@echo "NO_CORESIGHT - disable building coresight (arm64 only)"
 	@echo NO_UNICORN_ARM64 - disable building unicorn on arm64
+	@echo "WAFL_MODE - enable for WASM fuzzing with https://github.com/fgsect/WAFL"
 	@echo AFL_NO_X86 - if compiling on non-intel/amd platforms
 	@echo "LLVM_CONFIG - if your distro doesn't use the standard name for llvm-config (e.g., Debian)"
 	@echo "=========================================="

GNUmakefile.llvm

@@ -294,6 +294,11 @@ endif
 CLANG_CPPFL  = `$(LLVM_CONFIG) --cxxflags` -fno-rtti -fPIC $(CXXFLAGS) -Wno-deprecated-declarations
 CLANG_LFL    = `$(LLVM_CONFIG) --ldflags` $(LDFLAGS)
 
+# wasm fuzzing: disable thread-local storage and unset LLVM debug flag
+ifdef WAFL_MODE
+  $(info Compiling libraries for use with WAVM)
+  CLANG_CPPFL += -DNDEBUG -DNO_TLS
+endif
 
 # User teor2345 reports that this is required to make things work on MacOS X.
 ifeq "$(SYS)" "Darwin"

instrumentation/afl-compiler-rt.o.c

@@ -113,7 +113,7 @@ int        __afl_selective_coverage __attribute__((weak));
 int        __afl_selective_coverage_start_off __attribute__((weak));
 static int __afl_selective_coverage_temp = 1;
 
-#if defined(__ANDROID__) || defined(__HAIKU__)
+#if defined(__ANDROID__) || defined(__HAIKU__) || defined(NO_TLS)
 PREV_LOC_T __afl_prev_loc[NGRAM_SIZE_MAX];
 PREV_LOC_T __afl_prev_caller[CTX_MAX_K];
 u32        __afl_prev_ctx;

instrumentation/afl-llvm-pass.so.cc

@@ -413,7 +413,7 @@ bool AFLCoverage::runOnModule(Module &M) {
   GlobalVariable *AFLContext = NULL;
 
   if (ctx_str || caller_str)
-#if defined(__ANDROID__) || defined(__HAIKU__)
+#if defined(__ANDROID__) || defined(__HAIKU__) || defined(NO_TLS)
     AFLContext = new GlobalVariable(
         M, Int32Ty, false, GlobalValue::ExternalLinkage, 0, "__afl_prev_ctx");
 #else
@@ -424,7 +424,7 @@ bool AFLCoverage::runOnModule(Module &M) {
 
 #ifdef AFL_HAVE_VECTOR_INTRINSICS
   if (ngram_size)
-  #if defined(__ANDROID__) || defined(__HAIKU__)
+  #if defined(__ANDROID__) || defined(__HAIKU__) || defined(NO_TLS)
     AFLPrevLoc = new GlobalVariable(
         M, PrevLocTy, /* isConstant */ false, GlobalValue::ExternalLinkage,
         /* Initializer */ nullptr, "__afl_prev_loc");
@@ -437,7 +437,7 @@ bool AFLCoverage::runOnModule(Module &M) {
   #endif
   else
 #endif
-#if defined(__ANDROID__) || defined(__HAIKU__)
+#if defined(__ANDROID__) || defined(__HAIKU__) || defined(NO_TLS)
     AFLPrevLoc = new GlobalVariable(
         M, Int32Ty, false, GlobalValue::ExternalLinkage, 0, "__afl_prev_loc");
 #else
@@ -448,7 +448,7 @@ bool AFLCoverage::runOnModule(Module &M) {
 
 #ifdef AFL_HAVE_VECTOR_INTRINSICS
   if (ctx_k)
-  #if defined(__ANDROID__) || defined(__HAIKU__)
+  #if defined(__ANDROID__) || defined(__HAIKU__) || defined(NO_TLS)
     AFLPrevCaller = new GlobalVariable(
         M, PrevCallerTy, /* isConstant */ false, GlobalValue::ExternalLinkage,
         /* Initializer */ nullptr, "__afl_prev_caller");
@@ -461,7 +461,7 @@ bool AFLCoverage::runOnModule(Module &M) {
   #endif
   else
 #endif
-#if defined(__ANDROID__) || defined(__HAIKU__)
+#if defined(__ANDROID__) || defined(__HAIKU__) || defined(NO_TLS)
     AFLPrevCaller =
         new GlobalVariable(M, Int32Ty, false, GlobalValue::ExternalLinkage, 0,
                            "__afl_prev_caller");