SanitizerBlacklist: blacklist functions by their source location.

This commit changes the way we blacklist functions in ASan, TSan,
MSan and UBSan. We used to treat function as "blacklisted"
and turned off instrumentation in it in two cases:

1) Function is explicitly blacklisted by its mangled name.
This part is not changed.

2) Function is located in llvm::Module, whose identifier is
contained in the list of blacklisted sources. This is completely
wrong, as llvm::Module may not correspond to the actual source
file function is defined in. Also, function can be defined in
a header, in which case user had to blacklist the .cpp file
this header was #include'd into, not the header itself.
Such functions could cause other problems - for instance, if the
header was included in multiple source files, compiled
separately and linked into a single executable, we could end up
with both instrumented and non-instrumented version of the same
function participating in the same link.

After this change we will make blacklisting decision based on
the SourceLocation of a function definition. If a function is
not explicitly defined in the source file, (for example, the
function is compiler-generated and responsible for
initialization/destruction of a global variable), then it will
be blacklisted if the corresponding global variable is defined
in blacklisted source file, and will be instrumented otherwise.

After this commit, the active users of blacklist files may have
to revisit them. This is a backwards-incompatible change, but
I don't think it's possible or makes sense to support the
old incorrect behavior.

I plan to make similar change for blacklisting GlobalVariables
(which is ASan-specific).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219997 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Basic/SanitizerBlacklist.h

@@ -23,7 +23,6 @@
 
 namespace llvm {
 class GlobalVariable;
-class Function;
 }
 
 namespace clang {
@@ -34,7 +33,6 @@ class SanitizerBlacklist {
 
 public:
   SanitizerBlacklist(StringRef BlacklistPath, SourceManager &SM);
-  bool isIn(const llvm::Function &F) const;
   bool isIn(const llvm::GlobalVariable &G,
             StringRef Category = StringRef()) const;
   bool isBlacklistedType(StringRef MangledTypeName,

lib/Basic/SanitizerBlacklist.cpp

@@ -12,7 +12,6 @@
 //
 //===----------------------------------------------------------------------===//
 #include "clang/Basic/SanitizerBlacklist.h"
-#include "llvm/IR/Function.h"
 #include "llvm/IR/GlobalValue.h"
 #include "llvm/IR/Module.h"
 
@@ -33,11 +32,6 @@ SanitizerBlacklist::SanitizerBlacklist(StringRef BlacklistPath,
                                        SourceManager &SM)
     : SCL(llvm::SpecialCaseList::createOrDie(BlacklistPath)), SM(SM) {}
 
-bool SanitizerBlacklist::isIn(const llvm::Function &F) const {
-  return isBlacklistedFile(F.getParent()->getModuleIdentifier()) ||
-         isBlacklistedFunction(F.getName());
-}
-
 bool SanitizerBlacklist::isIn(const llvm::GlobalVariable &G,
                               StringRef Category) const {
   return isBlacklistedFile(G.getParent()->getModuleIdentifier(), Category) ||

lib/CodeGen/CGDeclCXX.cpp

@@ -167,7 +167,8 @@ llvm::Constant *CodeGenFunction::createAtExitStub(const VarDecl &VD,
     llvm::raw_svector_ostream Out(FnName);
     CGM.getCXXABI().getMangleContext().mangleDynamicAtExitDestructor(&VD, Out);
   }
-  llvm::Function *fn = CGM.CreateGlobalInitOrDestructFunction(ty, FnName.str());
+  llvm::Function *fn = CGM.CreateGlobalInitOrDestructFunction(ty, FnName.str(),
+                                                              VD.getLocation());
 
   CodeGenFunction CGF(CGM);
 
@@ -219,9 +220,8 @@ void CodeGenFunction::EmitCXXGuardedInit(const VarDecl &D,
   CGM.getCXXABI().EmitGuardedInit(*this, D, DeclPtr, PerformInit);
 }
 
-llvm::Function *
-CodeGenModule::CreateGlobalInitOrDestructFunction(llvm::FunctionType *FTy,
-                                                  const Twine &Name, bool TLS) {
+llvm::Function *CodeGenModule::CreateGlobalInitOrDestructFunction(
+    llvm::FunctionType *FTy, const Twine &Name, SourceLocation Loc, bool TLS) {
   llvm::Function *Fn =
     llvm::Function::Create(FTy, llvm::GlobalValue::InternalLinkage,
                            Name, &getModule());
@@ -236,7 +236,7 @@ CodeGenModule::CreateGlobalInitOrDestructFunction(llvm::FunctionType *FTy,
   if (!getLangOpts().Exceptions)
     Fn->setDoesNotThrow();
 
-  if (!getSanitizerBlacklist().isIn(*Fn)) {
+  if (!isInSanitizerBlacklist(Fn, Loc)) {
     if (getLangOpts().Sanitize.Address)
       Fn->addFnAttr(llvm::Attribute::SanitizeAddress);
     if (getLangOpts().Sanitize.Thread)
@@ -286,7 +286,8 @@ CodeGenModule::EmitCXXGlobalVarDeclInitFunc(const VarDecl *D,
   }
 
   // Create a variable initialization function.
-  llvm::Function *Fn = CreateGlobalInitOrDestructFunction(FTy, FnName.str());
+  llvm::Function *Fn =
+      CreateGlobalInitOrDestructFunction(FTy, FnName.str(), D->getLocation());
 
   auto *ISA = D->getAttr<InitSegAttr>();
   CodeGenFunction(*this).GenerateCXXGlobalVarDeclInitFunc(Fn, D, Addr,
@@ -552,8 +553,8 @@ llvm::Function *CodeGenFunction::generateDestroyHelper(
   const CGFunctionInfo &FI = CGM.getTypes().arrangeFreeFunctionDeclaration(
       getContext().VoidTy, args, FunctionType::ExtInfo(), /*variadic=*/false);
   llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(FI);
-  llvm::Function *fn =
-      CGM.CreateGlobalInitOrDestructFunction(FTy, "__cxx_global_array_dtor");
+  llvm::Function *fn = CGM.CreateGlobalInitOrDestructFunction(
+      FTy, "__cxx_global_array_dtor", VD->getLocation());
 
   StartFunction(VD, getContext().VoidTy, fn, FI, args);
 

lib/CodeGen/CGExpr.cpp

@@ -552,7 +552,8 @@ void CodeGenFunction::EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc,
                                                      Out);
 
     // Blacklist based on the mangled type.
-    if (!CGM.getSanitizerBlacklist().isBlacklistedType(Out.str())) {
+    if (!CGM.getContext().getSanitizerBlacklist().isBlacklistedType(
+            Out.str())) {
       llvm::hash_code TypeHash = hash_value(Out.str());
 
       // Load the vptr, and compute hash_16_bytes(TypeHash, vptr).

lib/CodeGen/CodeGenFunction.cpp

@@ -579,7 +579,7 @@ void CodeGenFunction::StartFunction(GlobalDecl GD,
   CurFnInfo = &FnInfo;
   assert(CurFn->isDeclaration() && "Function already has body?");
 
-  if (CGM.getSanitizerBlacklist().isIn(*Fn))
+  if (CGM.isInSanitizerBlacklist(Fn, Loc))
     SanOpts = &SanitizerOptions::Disabled;
 
   // Pass inline keyword to optimizer if it appears explicitly on any

lib/CodeGen/CodeGenModule.cpp

@@ -740,7 +740,7 @@ void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
     B.addAttribute(llvm::Attribute::StackProtectReq);
 
   // Add sanitizer attributes if function is not blacklisted.
-  if (!getSanitizerBlacklist().isIn(*F)) {
+  if (!isInSanitizerBlacklist(F, D->getLocation())) {
     // When AddressSanitizer is enabled, set SanitizeAddress attribute
     // unless __attribute__((no_sanitize_address)) is used.
     if (LangOpts.Sanitize.Address && !D->hasAttr<NoSanitizeAddressAttr>())
@@ -1168,6 +1168,24 @@ void CodeGenModule::AddGlobalAnnotations(const ValueDecl *D,
     Annotations.push_back(EmitAnnotateAttr(GV, I, D->getLocation()));
 }
 
+bool CodeGenModule::isInSanitizerBlacklist(llvm::Function *Fn,
+                                           SourceLocation Loc) const {
+  const auto &SanitizerBL = getContext().getSanitizerBlacklist();
+  // Blacklist by function name.
+  if (SanitizerBL.isBlacklistedFunction(Fn->getName()))
+    return true;
+  // Blacklist by location.
+  if (!Loc.isInvalid())
+    return SanitizerBL.isBlacklistedLocation(Loc);
+  // If location is unknown, this may be a compiler-generated function. Assume
+  // it's located in the main file.
+  auto &SM = Context.getSourceManager();
+  if (const auto *MainFile = SM.getFileEntryForID(SM.getMainFileID())) {
+    return SanitizerBL.isBlacklistedFile(MainFile->getName());
+  }
+  return false;
+}
+
 bool CodeGenModule::MayDeferGeneration(const ValueDecl *Global) {
   // Never defer when EmitAllDecls is specified.
   if (LangOpts.EmitAllDecls)

lib/CodeGen/CodeGenModule.h

@@ -686,9 +686,10 @@ public:
   CreateOrReplaceCXXRuntimeVariable(StringRef Name, llvm::Type *Ty,
                                     llvm::GlobalValue::LinkageTypes Linkage);
 
-  llvm::Function *CreateGlobalInitOrDestructFunction(llvm::FunctionType *ty,
-                                                     const Twine &name,
-                                                     bool TLS = false);
+  llvm::Function *
+  CreateGlobalInitOrDestructFunction(llvm::FunctionType *ty, const Twine &name,
+                                     SourceLocation Loc = SourceLocation(),
+                                     bool TLS = false);
 
   /// Return the address space of the underlying global variable for D, as
   /// determined by its declaration. Normally this is the same as the address
@@ -1045,9 +1046,7 @@ public:
   /// annotations are emitted during finalization of the LLVM code.
   void AddGlobalAnnotations(const ValueDecl *D, llvm::GlobalValue *GV);
 
-  const SanitizerBlacklist &getSanitizerBlacklist() const {
-    return Context.getSanitizerBlacklist();
-  }
+  bool isInSanitizerBlacklist(llvm::Function *Fn, SourceLocation Loc) const;
 
   SanitizerMetadata *getSanitizerMetadata() {
     return SanitizerMD.get();

lib/CodeGen/ItaniumCXXABI.cpp

@@ -1912,6 +1912,7 @@ void ItaniumCXXABI::EmitThreadLocalInitFuncs(
     llvm::FunctionType *FTy =
         llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
     InitFunc = CGM.CreateGlobalInitOrDestructFunction(FTy, "__tls_init",
+                                                      SourceLocation(),
                                                       /*TLS=*/true);
     llvm::GlobalVariable *Guard = new llvm::GlobalVariable(
         CGM.getModule(), CGM.Int8Ty, /*isConstant=*/false,

lib/CodeGen/MicrosoftCXXABI.cpp

@@ -1796,9 +1796,9 @@ void MicrosoftCXXABI::EmitThreadLocalInitFuncs(
   if (!NonComdatInits.empty()) {
     llvm::FunctionType *FTy =
         llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
-    llvm::Function *InitFunc =
-        CGM.CreateGlobalInitOrDestructFunction(FTy, "__tls_init",
-                                               /*TLS=*/true);
+    llvm::Function *InitFunc = CGM.CreateGlobalInitOrDestructFunction(
+        FTy, "__tls_init", SourceLocation(),
+        /*TLS=*/true);
     CodeGenFunction(CGM).GenerateCXXGlobalInitFunc(InitFunc, NonComdatInits);
 
     AddToXDU(InitFunc);

lib/CodeGen/SanitizerMetadata.cpp

@@ -25,8 +25,8 @@ void SanitizerMetadata::reportGlobalToASan(llvm::GlobalVariable *GV,
                                            bool IsDynInit, bool IsBlacklisted) {
   if (!CGM.getLangOpts().Sanitize.Address)
     return;
-  IsDynInit &= !CGM.getSanitizerBlacklist().isIn(*GV, "init");
-  IsBlacklisted |= CGM.getSanitizerBlacklist().isIn(*GV);
+  IsDynInit &= !CGM.getContext().getSanitizerBlacklist().isIn(*GV, "init");
+  IsBlacklisted |= CGM.getContext().getSanitizerBlacklist().isIn(*GV);
 
   llvm::Value *LocDescr = nullptr;
   llvm::Value *GlobalName = nullptr;

test/CodeGen/address-safety-attr.cpp

@@ -1,9 +1,16 @@
-// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s | FileCheck -check-prefix=WITHOUT %s
-// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s -fsanitize=address | FileCheck -check-prefix=ASAN %s
-// RUN: echo "src:%s" > %t.file.blacklist
+int DefinedInDifferentFile(int *a);
+// RUN: echo "int DefinedInDifferentFile(int *a) { return *a; }" > %t.extra-source.cpp
+// RUN: echo "struct S { S(){} ~S(){} };" >> %t.extra-source.cpp
+// RUN: echo "S glob_array[5];" >> %t.extra-source.cpp
+
+// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s -include %t.extra-source.cpp | FileCheck -check-prefix=WITHOUT %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s -include %t.extra-source.cpp -fsanitize=address | FileCheck -check-prefix=ASAN %s
+
 // RUN: echo "fun:*BlacklistedFunction*" > %t.func.blacklist
-// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s -fsanitize=address -fsanitize-blacklist=%t.file.blacklist | FileCheck -check-prefix=BLFILE %s
-// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s -fsanitize=address -fsanitize-blacklist=%t.func.blacklist | FileCheck -check-prefix=BLFUNC %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s -include %t.extra-source.cpp -fsanitize=address -fsanitize-blacklist=%t.func.blacklist | FileCheck -check-prefix=BLFUNC %s
+
+// RUN: echo "src:%s" > %t.file.blacklist
+// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s -include %t.extra-source.cpp -fsanitize=address -fsanitize-blacklist=%t.file.blacklist | FileCheck -check-prefix=BLFILE %s
 
 // FIXME: %t.file.blacklist is like "src:x:\path\to\clang\test\CodeGen\address-safety-attr.cpp"
 // REQUIRES: shell
@@ -12,7 +19,25 @@
 // when AddressSanitizer is enabled, unless no_sanitize_address attribute
 // is present.
 
-// WITHOUT:  NoAddressSafety1{{.*}}) [[NOATTR:#[0-9]+]]
+// Attributes for function defined in different source file:
+// WITHOUT: DefinedInDifferentFile{{.*}} [[NOATTR:#[0-9]+]]
+// BLFILE:  DefinedInDifferentFile{{.*}} [[WITH:#[0-9]+]]
+// BLFUNC:  DefinedInDifferentFile{{.*}} [[WITH:#[0-9]+]]
+// ASAN:    DefinedInDifferentFile{{.*}} [[WITH:#[0-9]+]]
+
+// Check that functions generated for global in different source file are
+// not blacklisted.
+// WITHOUT: @__cxx_global_var_init{{.*}}[[NOATTR_NO_TF:#[0-9]+]]
+// WITHOUT: @__cxx_global_array_dtor{{.*}}[[NOATTR_NO_TF]]
+// BLFILE: @__cxx_global_var_init{{.*}}[[WITH_NO_TF:#[0-9]+]]
+// BLFILE: @__cxx_global_array_dtor{{.*}}[[WITH_NO_TF]]
+// BLFUNC: @__cxx_global_var_init{{.*}}[[WITH_NO_TF:#[0-9]+]]
+// BLFUNC: @__cxx_global_array_dtor{{.*}}[[WITH_NO_TF]]
+// ASAN: @__cxx_global_var_init{{.*}}[[WITH_NO_TF:#[0-9]+]]
+// ASAN: @__cxx_global_array_dtor{{.*}}[[WITH_NO_TF]]
+
+
+// WITHOUT:  NoAddressSafety1{{.*}}) [[NOATTR]]
 // BLFILE:  NoAddressSafety1{{.*}}) [[NOATTR:#[0-9]+]]
 // BLFUNC:  NoAddressSafety1{{.*}}) [[NOATTR:#[0-9]+]]
 // ASAN:  NoAddressSafety1{{.*}}) [[NOATTR:#[0-9]+]]
@@ -29,8 +54,8 @@ int NoAddressSafety2(int *a) { return *a; }
 
 // WITHOUT:  AddressSafetyOk{{.*}}) [[NOATTR]]
 // BLFILE:  AddressSafetyOk{{.*}}) [[NOATTR]]
-// BLFUNC: AddressSafetyOk{{.*}}) [[WITH:#[0-9]+]]
-// ASAN: AddressSafetyOk{{.*}}) [[WITH:#[0-9]+]]
+// BLFUNC: AddressSafetyOk{{.*}}) [[WITH]]
+// ASAN: AddressSafetyOk{{.*}}) [[WITH]]
 int AddressSafetyOk(int *a) { return *a; }
 
 // WITHOUT:  BlacklistedFunction{{.*}}) [[NOATTR]]
@@ -60,21 +85,23 @@ int force_instance = TemplateAddressSafetyOk<42>()
 // Check that __cxx_global_var_init* get the sanitize_address attribute.
 int global1 = 0;
 int global2 = *(int*)((char*)&global1+1);
-// WITHOUT: @__cxx_global_var_init{{.*}}[[NOATTR_NO_TF:#[0-9]+]]
+// WITHOUT: @__cxx_global_var_init{{.*}}[[NOATTR_NO_TF]]
 // BLFILE: @__cxx_global_var_init{{.*}}[[NOATTR_NO_TF:#[0-9]+]]
-// BLFUNC: @__cxx_global_var_init{{.*}}[[WITH_NO_TF:#[0-9]+]]
-// ASAN: @__cxx_global_var_init{{.*}}[[WITH_NO_TF:#[0-9]+]]
+// BLFUNC: @__cxx_global_var_init{{.*}}[[WITH_NO_TF]]
+// ASAN: @__cxx_global_var_init{{.*}}[[WITH_NO_TF]]
 
 // WITHOUT: attributes [[NOATTR]] = { nounwind{{.*}} }
 // WITHOUT: attributes [[NOATTR_NO_TF]] = { nounwind }
 
-// BLFILE: attributes [[NOATTR]] = { nounwind{{.*}} }
+// BLFILE: attributes [[WITH]] = { nounwind sanitize_address{{.*}} }
+// BLFILE: attributes [[WITH_NO_TF]] = { nounwind sanitize_address }
 // BLFILE: attributes [[NOATTR_NO_TF]] = { nounwind }
+// BLFILE: attributes [[NOATTR]] = { nounwind{{.*}} }
 
-// BLFUNC: attributes [[NOATTR]] = { nounwind{{.*}} }
 // BLFUNC: attributes [[WITH]] = { nounwind sanitize_address{{.*}} }
 // BLFUNC: attributes [[WITH_NO_TF]] = { nounwind sanitize_address }
+// BLFUNC: attributes [[NOATTR]] = { nounwind{{.*}} }
 
-// ASAN: attributes [[NOATTR]] = { nounwind{{.*}} }
 // ASAN: attributes [[WITH]] = { nounwind sanitize_address{{.*}} }
 // ASAN: attributes [[WITH_NO_TF]] = { nounwind sanitize_address }
+// ASAN: attributes [[NOATTR]] = { nounwind{{.*}} }