Implement -fsanitize-recover for ASan and MSan. (#4783)

Resolves #4770

driver/cl_options_sanitizers.cpp

@@ -50,6 +50,12 @@ cl::list<std::string> fSanitizeCoverage(
 
 llvm::SanitizerCoverageOptions sanitizerCoverageOptions;
 
+cl::list<std::string>
+    fSanitizeRecover("fsanitize-recover", cl::CommaSeparated,
+                     cl::desc("Enable recovery for specified sanitizers ('all' "
+                              "= enable for all supported sanitizers)."),
+                     cl::value_desc("name"));
+
 SanitizerBits parseFSanitizeCmdlineParameter() {
   SanitizerBits retval = 0;
   for (const auto &name : fSanitize) {
@@ -61,6 +67,24 @@ SanitizerBits parseFSanitizeCmdlineParameter() {
   return retval;
 }
 
+SanitizerBits parseFSanitizeRecoverCmdlineParameter() {
+  SanitizerBits retval = 0;
+  for (const auto &name : fSanitizeRecover) {
+    if (name == "all") {
+      retval |= ~SanitizerBits(0);
+      continue;
+    }
+    SanitizerCheck check = parseSanitizerName(name, [&name] {
+      error(Loc(), "fsanitize-recover: Unrecognized sanitizer name '%s'.", name.c_str());
+    });
+    if (check & supportedSanitizerRecoveries)
+      retval |= SanitizerBits(check);
+    else
+      error(Loc(), "fsanitize-recover: Recovery not supported for '%s'.", name.c_str());
+  }
+  return retval;
+}
+
 void parseFSanitizeCoverageParameter(llvm::StringRef name,
                                      llvm::SanitizerCoverageOptions &opts) {
   if (name == "func") {
@@ -148,6 +172,8 @@ cl::opt<llvm::AsanDetectStackUseAfterReturnMode> fSanitizeAddressUseAfterReturn(
             "but not as much as never). Requires druntime support.")));
 
 SanitizerBits enabledSanitizers = 0;
+SanitizerBits enabledSanitizerRecoveries = 0;
+const SanitizerBits supportedSanitizerRecoveries = AddressSanitizer | MemorySanitizer;
 
 // Parse sanitizer name passed on commandline and return the corresponding
 // sanitizer bits.
@@ -171,6 +197,7 @@ SanitizerCheck parseSanitizerName(llvm::StringRef name,
 void initializeSanitizerOptionsFromCmdline()
 {
   enabledSanitizers |= parseFSanitizeCmdlineParameter();
+  enabledSanitizerRecoveries |= parseFSanitizeRecoverCmdlineParameter();
 
   auto &sancovOpts = sanitizerCoverageOptions;
 

driver/cl_options_sanitizers.h

@@ -37,6 +37,8 @@ enum SanitizerCheck : SanitizerBits {
   LeakSanitizer = 1 << 5,
 };
 extern SanitizerBits enabledSanitizers;
+extern SanitizerBits enabledSanitizerRecoveries;
+extern const SanitizerBits supportedSanitizerRecoveries;
 
 extern cl::opt<llvm::AsanDetectStackUseAfterReturnMode> fSanitizeAddressUseAfterReturn;
 
@@ -45,6 +47,10 @@ inline bool isSanitizerEnabled(SanitizerBits san) {
   return enabledSanitizers & san;
 }
 
+inline bool isSanitizerRecoveryEnabled(SanitizerBits san) {
+  return enabledSanitizerRecoveries & san;
+}
+
 SanitizerCheck parseSanitizerName(llvm::StringRef name,
                                   std::function<void()> actionUponError);
 

driver/linker-gcc.cpp

@@ -508,6 +508,13 @@ void ArgsBuilder::addSanitizers(const llvm::Triple &triple) {
   if (opts::isSanitizerEnabled(opts::ThreadSanitizer)) {
     addSanitizerLinkFlags(triple, "tsan", "-fsanitize=thread");
   }
+
+  if (opts::isSanitizerRecoveryEnabled(opts::AddressSanitizer)) {
+      args.push_back("-fsanitize-recover=address");
+  }
+  if (opts::isSanitizerRecoveryEnabled(opts::MemorySanitizer)) {
+      args.push_back("-fsanitize-recover=memory");
+  }
 }
 
 //////////////////////////////////////////////////////////////////////////////

gen/optimizer.cpp

@@ -184,7 +184,7 @@ static void addAddressSanitizerPasses(ModulePassManager &mpm,
                                       OptimizationLevel level ) {
   AddressSanitizerOptions aso;
   aso.CompileKernel = false;
-  aso.Recover = false;
+  aso.Recover = opts::isSanitizerRecoveryEnabled(opts::AddressSanitizer);
   aso.UseAfterScope = true;
   aso.UseAfterReturn = opts::fSanitizeAddressUseAfterReturn;
 
@@ -199,7 +199,7 @@ static void addMemorySanitizerPass(ModulePassManager &mpm,
                                    FunctionPassManager &fpm,
                                    OptimizationLevel level ) {
   int trackOrigins = fSanitizeMemoryTrackOrigins;
-  bool recover = false;
+  bool recover = opts::isSanitizerRecoveryEnabled(opts::MemorySanitizer);
   bool kernel = false;
 #if LDC_LLVM_VER >= 1600
   mpm.addPass(MemorySanitizerPass(

tests/sanitizers/asan_recover_stackoverflow.d

@@ -0,0 +1,32 @@
+// Test recovery with AddressSanitizer
+
+// REQUIRES: ASan
+
+// RUN: %ldc -g -fsanitize=address -fsanitize-recover=address %s -of=%t%exe
+// RUN: not %t%exe 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=halt_on_error=true not %t%exe 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=halt_on_error=false %t%exe 2>&1 | FileCheck %s
+
+// RUN: %ldc -g -fsanitize=address -fsanitize-recover=all %s -of=%t%exe
+// RUN: not %t%exe 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=halt_on_error=true not %t%exe 2>&1 | FileCheck %s
+// RUN: %env_asan_opts=halt_on_error=false %t%exe 2>&1 | FileCheck %s
+
+void foo(int* arr)
+{
+    // CHECK: stack-buffer-overflow
+    // CHECK: WRITE of size 4
+    // CHECK-NEXT: #0 {{.*}} in {{.*foo.*}} {{.*}}asan_recover_stackoverflow.d:[[@LINE+1]]
+    arr[10] = 1;
+}
+
+// CHECK: Address {{.*}} is located in stack of
+// CHECK-NEXT: #0 {{.*}} in {{.*main.*}} {{.*}}asan_recover_stackoverflow.d:[[@LINE+1]]
+void main()
+{
+    // Test for the name of the variable that is overflown.
+    // CHECK: 'aiaiaiaiaiaiai'{{.*}} <== {{.*}} overflows this variable
+    int[10] aiaiaiaiaiaiai;
+    int b;
+    foo(&aiaiaiaiaiaiai[0]);
+}