#include "llvm/Support/CommandLine.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/Endian.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/system_error.h"
-#include "llvm/Target/TargetMachine.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/Transforms/Utils/BlackList.h"
+#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/ModuleUtils.h"
+#include "llvm/Transforms/Utils/SpecialCaseList.h"
#include <algorithm>
#include <string>
static const uint64_t kDefaultShadowOffset64 = 1ULL << 44;
static const uint64_t kDefaultShort64bitShadowOffset = 0x7FFF8000; // < 2G.
static const uint64_t kPPC64_ShadowOffset64 = 1ULL << 41;
+static const uint64_t kMIPS32_ShadowOffset32 = 0x0aaa8000;
static const size_t kMaxStackMallocSize = 1 << 16; // 64K
static const uintptr_t kCurrentStackFrameMagic = 0x41B58AB3;
static const uintptr_t kRetiredStackFrameMagic = 0x45E0360E;
-static const char *kAsanModuleCtorName = "asan.module_ctor";
-static const char *kAsanModuleDtorName = "asan.module_dtor";
-static const int kAsanCtorAndCtorPriority = 1;
-static const char *kAsanReportErrorTemplate = "__asan_report_";
-static const char *kAsanReportLoadN = "__asan_report_load_n";
-static const char *kAsanReportStoreN = "__asan_report_store_n";
-static const char *kAsanRegisterGlobalsName = "__asan_register_globals";
-static const char *kAsanUnregisterGlobalsName = "__asan_unregister_globals";
-static const char *kAsanPoisonGlobalsName = "__asan_before_dynamic_init";
-static const char *kAsanUnpoisonGlobalsName = "__asan_after_dynamic_init";
-static const char *kAsanInitName = "__asan_init_v2";
-static const char *kAsanHandleNoReturnName = "__asan_handle_no_return";
-static const char *kAsanMappingOffsetName = "__asan_mapping_offset";
-static const char *kAsanMappingScaleName = "__asan_mapping_scale";
-static const char *kAsanStackMallocName = "__asan_stack_malloc";
-static const char *kAsanStackFreeName = "__asan_stack_free";
-static const char *kAsanGenPrefix = "__asan_gen_";
-static const char *kAsanPoisonStackMemoryName = "__asan_poison_stack_memory";
-static const char *kAsanUnpoisonStackMemoryName =
+static const char *const kAsanModuleCtorName = "asan.module_ctor";
+static const char *const kAsanModuleDtorName = "asan.module_dtor";
+static const int kAsanCtorAndCtorPriority = 1;
+static const char *const kAsanReportErrorTemplate = "__asan_report_";
+static const char *const kAsanReportLoadN = "__asan_report_load_n";
+static const char *const kAsanReportStoreN = "__asan_report_store_n";
+static const char *const kAsanRegisterGlobalsName = "__asan_register_globals";
+static const char *const kAsanUnregisterGlobalsName = "__asan_unregister_globals";
+static const char *const kAsanPoisonGlobalsName = "__asan_before_dynamic_init";
+static const char *const kAsanUnpoisonGlobalsName = "__asan_after_dynamic_init";
+static const char *const kAsanInitName = "__asan_init_v3";
+static const char *const kAsanHandleNoReturnName = "__asan_handle_no_return";
+static const char *const kAsanMappingOffsetName = "__asan_mapping_offset";
+static const char *const kAsanMappingScaleName = "__asan_mapping_scale";
+static const char *const kAsanStackMallocName = "__asan_stack_malloc";
+static const char *const kAsanStackFreeName = "__asan_stack_free";
+static const char *const kAsanGenPrefix = "__asan_gen_";
+static const char *const kAsanPoisonStackMemoryName =
+ "__asan_poison_stack_memory";
+static const char *const kAsanUnpoisonStackMemoryName =
"__asan_unpoison_stack_memory";
static const int kAsanStackLeftRedzoneMagic = 0xf1;
cl::desc("File containing the list of objects to ignore "
"during instrumentation"), cl::Hidden);
+// This is an experimental feature that will allow to choose between
+// instrumented and non-instrumented code at link-time.
+// If this option is on, just before instrumenting a function we create its
+// clone; if the function is not changed by asan the clone is deleted.
+// If we end up with a clone, we put the instrumented function into a section
+// called "ASAN" and the uninstrumented function into a section called "NOASAN".
+//
+// This is still a prototype, we need to figure out a way to keep two copies of
+// a function so that the linker can easily choose one of them.
+static cl::opt<bool> ClKeepUninstrumented("asan-keep-uninstrumented-functions",
+ cl::desc("Keep uninstrumented copies of functions"),
+ cl::Hidden, cl::init(false));
+
// These flags allow to change the shadow mapping.
// The shadow mapping looks like
// Shadow = (Mem >> scale) + (1 << offset_log)
llvm::Triple TargetTriple(M.getTargetTriple());
bool IsAndroid = TargetTriple.getEnvironment() == llvm::Triple::Android;
bool IsMacOSX = TargetTriple.getOS() == llvm::Triple::MacOSX;
- bool IsPPC64 = TargetTriple.getArch() == llvm::Triple::ppc64;
+ bool IsPPC64 = TargetTriple.getArch() == llvm::Triple::ppc64 ||
+ TargetTriple.getArch() == llvm::Triple::ppc64le;
bool IsX86_64 = TargetTriple.getArch() == llvm::Triple::x86_64;
+ bool IsMIPS32 = TargetTriple.getArch() == llvm::Triple::mips ||
+ TargetTriple.getArch() == llvm::Triple::mipsel;
ShadowMapping Mapping;
Mapping.OrShadowOffset = !IsPPC64 && !ClShort64BitOffset;
Mapping.Offset = (IsAndroid || ZeroBaseShadow) ? 0 :
- (LongSize == 32 ? kDefaultShadowOffset32 :
+ (LongSize == 32 ?
+ (IsMIPS32 ? kMIPS32_ShadowOffset32 : kDefaultShadowOffset32) :
IsPPC64 ? kPPC64_ShadowOffset64 : kDefaultShadowOffset64);
if (!ZeroBaseShadow && ClShort64BitOffset && IsX86_64 && !IsMacOSX) {
assert(LongSize == 64);
Instruction *InsertBefore, bool IsWrite);
Value *memToShadow(Value *Shadow, IRBuilder<> &IRB);
bool runOnFunction(Function &F);
- void createInitializerPoisonCalls(Module &M,
- Value *FirstAddr, Value *LastAddr);
bool maybeInsertAsanInitAtFunctionEntry(Function &F);
void emitShadowMapping(Module &M, IRBuilder<> &IRB) const;
virtual bool doInitialization(Module &M);
Function *AsanCtorFunction;
Function *AsanInitFunction;
Function *AsanHandleNoReturnFunc;
- OwningPtr<BlackList> BL;
+ OwningPtr<SpecialCaseList> BL;
// This array is indexed by AccessIsWrite and log2(AccessSize).
Function *AsanErrorCallback[2][kNumberOfAccessSizes];
// This array is indexed by AccessIsWrite.
void initializeCallbacks(Module &M);
bool ShouldInstrumentGlobal(GlobalVariable *G);
- void createInitializerPoisonCalls(Module &M, Value *FirstAddr,
- Value *LastAddr);
+ void createInitializerPoisonCalls(Module &M, GlobalValue *ModuleName);
size_t RedzoneSize() const {
return RedzoneSizeForScale(Mapping.Scale);
}
SmallString<64> BlacklistFile;
bool ZeroBaseShadow;
- OwningPtr<BlackList> BL;
+ OwningPtr<SpecialCaseList> BL;
SetOfDynamicallyInitializedGlobals DynamicallyInitializedGlobals;
Type *IntptrTy;
LLVMContext *C;
StackAlignment = std::max(StackAlignment, AI.getAlignment());
AllocaVec.push_back(&AI);
- uint64_t AlignedSize = getAlignedAllocaSize(&AI);
+ uint64_t AlignedSize = getAlignedAllocaSize(&AI);
TotalStackSize += AlignedSize;
}
bool isInterestingAlloca(AllocaInst &AI) {
return (!AI.isArrayAllocation() &&
AI.isStaticAlloca() &&
+ AI.getAlignment() <= RedzoneSize() &&
AI.getAllocatedType()->isSized());
}
}
static size_t TypeSizeToSizeIndex(uint32_t TypeSize) {
- size_t Res = CountTrailingZeros_32(TypeSize / 8);
+ size_t Res = countTrailingZeros(TypeSize / 8);
assert(Res < kNumberOfAccessSizes);
return Res;
}
// Create a constant for Str so that we can pass it to the run-time lib.
static GlobalVariable *createPrivateGlobalForString(Module &M, StringRef Str) {
Constant *StrConst = ConstantDataArray::getString(M.getContext(), Str);
- return new GlobalVariable(M, StrConst->getType(), true,
+ GlobalVariable *GV = new GlobalVariable(M, StrConst->getType(), true,
GlobalValue::PrivateLinkage, StrConst,
kAsanGenPrefix);
+ GV->setUnnamedAddr(true); // Ok to merge these.
+ GV->setAlignment(1); // Strings may not be merged w/o setting align 1.
+ return GV;
}
static bool GlobalWasGeneratedByAsan(GlobalVariable *G) {
}
void AddressSanitizerModule::createInitializerPoisonCalls(
- Module &M, Value *FirstAddr, Value *LastAddr) {
+ Module &M, GlobalValue *ModuleName) {
// We do all of our poisoning and unpoisoning within _GLOBAL__I_a.
Function *GlobalInit = M.getFunction("_GLOBAL__I_a");
// If that function is not present, this TU contains no globals, or they have
IRBuilder<> IRB(GlobalInit->begin()->getFirstInsertionPt());
// Add a call to poison all external globals before the given function starts.
- IRB.CreateCall2(AsanPoisonGlobals, FirstAddr, LastAddr);
+ Value *ModuleNameAddr = ConstantExpr::getPointerCast(ModuleName, IntptrTy);
+ IRB.CreateCall(AsanPoisonGlobals, ModuleNameAddr);
// Add calls to unpoison all globals before each return instruction.
for (Function::iterator I = GlobalInit->begin(), E = GlobalInit->end();
IRBuilder<> IRB(*C);
// Declare our poisoning and unpoisoning functions.
AsanPoisonGlobals = checkInterfaceFunction(M.getOrInsertFunction(
- kAsanPoisonGlobalsName, IRB.getVoidTy(), IntptrTy, IntptrTy, NULL));
+ kAsanPoisonGlobalsName, IRB.getVoidTy(), IntptrTy, NULL));
AsanPoisonGlobals->setLinkage(Function::ExternalLinkage);
AsanUnpoisonGlobals = checkInterfaceFunction(M.getOrInsertFunction(
kAsanUnpoisonGlobalsName, IRB.getVoidTy(), NULL));
TD = getAnalysisIfAvailable<DataLayout>();
if (!TD)
return false;
- BL.reset(new BlackList(BlacklistFile));
+ BL.reset(new SpecialCaseList(BlacklistFile));
if (BL->isIn(M)) return false;
C = &(M.getContext());
int LongSize = TD->getPointerSizeInBits();
assert(CtorFunc);
IRBuilder<> IRB(CtorFunc->getEntryBlock().getTerminator());
- // The addresses of the first and last dynamically initialized globals in
- // this TU. Used in initialization order checking.
- Value *FirstDynamic = 0, *LastDynamic = 0;
+ bool HasDynamicallyInitializedGlobals = false;
GlobalVariable *ModuleName = createPrivateGlobalForString(
M, M.getModuleIdentifier());
+ // We shouldn't merge same module names, as this string serves as unique
+ // module ID in runtime.
+ ModuleName->setUnnamedAddr(false);
for (size_t i = 0; i < n; i++) {
static const uint64_t kMaxGlobalRedzone = 1 << 18;
bool GlobalHasDynamicInitializer =
DynamicallyInitializedGlobals.Contains(G);
// Don't check initialization order if this global is blacklisted.
- GlobalHasDynamicInitializer &= !BL->isInInit(*G);
+ GlobalHasDynamicInitializer &= !BL->isIn(*G, "init");
StructType *NewTy = StructType::get(Ty, RightRedZoneTy, NULL);
Constant *NewInitializer = ConstantStruct::get(
NULL);
// Populate the first and last globals declared in this TU.
- if (CheckInitOrder && GlobalHasDynamicInitializer) {
- LastDynamic = ConstantExpr::getPointerCast(NewGlobal, IntptrTy);
- if (FirstDynamic == 0)
- FirstDynamic = LastDynamic;
- }
+ if (CheckInitOrder && GlobalHasDynamicInitializer)
+ HasDynamicallyInitializedGlobals = true;
DEBUG(dbgs() << "NEW GLOBAL: " << *NewGlobal << "\n");
}
ConstantArray::get(ArrayOfGlobalStructTy, Initializers), "");
// Create calls for poisoning before initializers run and unpoisoning after.
- if (CheckInitOrder && FirstDynamic && LastDynamic)
- createInitializerPoisonCalls(M, FirstDynamic, LastDynamic);
+ if (CheckInitOrder && HasDynamicallyInitializedGlobals)
+ createInitializerPoisonCalls(M, ModuleName);
IRB.CreateCall2(AsanRegisterGlobals,
IRB.CreatePointerCast(AllGlobals, IntptrTy),
ConstantInt::get(IntptrTy, n));
if (!TD)
return false;
- BL.reset(new BlackList(BlacklistFile));
+ BL.reset(new SpecialCaseList(BlacklistFile));
DynamicallyInitializedGlobals.Init(M);
C = &(M.getContext());
// If needed, insert __asan_init before checking for SanitizeAddress attr.
maybeInsertAsanInitAtFunctionEntry(F);
- if (!F.getAttributes().hasAttribute(AttributeSet::FunctionIndex,
- Attribute::SanitizeAddress))
+ if (!F.hasFnAttribute(Attribute::SanitizeAddress))
return false;
if (!ClDebugFunc.empty() && ClDebugFunc != F.getName())
SmallSet<Value*, 16> TempsToInstrument;
SmallVector<Instruction*, 16> ToInstrument;
SmallVector<Instruction*, 8> NoReturnCalls;
+ int NumAllocas = 0;
bool IsWrite;
// Fill the set of memory operations to instrument.
} else if (isa<MemIntrinsic>(BI) && ClMemIntrin) {
// ok, take it.
} else {
+ if (isa<AllocaInst>(BI))
+ NumAllocas++;
CallSite CS(BI);
if (CS) {
// A call inside BB.
}
}
+ Function *UninstrumentedDuplicate = 0;
+ bool LikelyToInstrument =
+ !NoReturnCalls.empty() || !ToInstrument.empty() || (NumAllocas > 0);
+ if (ClKeepUninstrumented && LikelyToInstrument) {
+ ValueToValueMapTy VMap;
+ UninstrumentedDuplicate = CloneFunction(&F, VMap, false);
+ UninstrumentedDuplicate->removeFnAttr(Attribute::SanitizeAddress);
+ UninstrumentedDuplicate->setName("NOASAN_" + F.getName());
+ F.getParent()->getFunctionList().push_back(UninstrumentedDuplicate);
+ }
+
// Instrument.
int NumInstrumented = 0;
for (size_t i = 0, n = ToInstrument.size(); i != n; i++) {
IRBuilder<> IRB(CI);
IRB.CreateCall(AsanHandleNoReturnFunc);
}
- DEBUG(dbgs() << "ASAN done instrumenting:\n" << F << "\n");
- return NumInstrumented > 0 || ChangedStack || !NoReturnCalls.empty();
+ bool res = NumInstrumented > 0 || ChangedStack || !NoReturnCalls.empty();
+ DEBUG(dbgs() << "ASAN done instrumenting: " << res << " " << F << "\n");
+
+ if (ClKeepUninstrumented) {
+ if (!res) {
+ // No instrumentation is done, no need for the duplicate.
+ if (UninstrumentedDuplicate)
+ UninstrumentedDuplicate->eraseFromParent();
+ } else {
+ // The function was instrumented. We must have the duplicate.
+ assert(UninstrumentedDuplicate);
+ UninstrumentedDuplicate->setSection("NOASAN");
+ assert(!F.hasSection());
+ F.setSection("ASAN");
+ }
+ }
+
+ return res;
}
static uint64_t ValueForPoison(uint64_t PoisonByte, size_t ShadowRedzoneSize) {
RedzoneSize(),
1ULL << Mapping.Scale,
kAsanStackPartialRedzoneMagic);
+ Poison =
+ ASan.TD->isLittleEndian()
+ ? support::endian::byte_swap<uint32_t, support::little>(Poison)
+ : support::endian::byte_swap<uint32_t, support::big>(Poison);
}
Value *PartialPoison = ConstantInt::get(RZTy, Poison);
IRB.CreateStore(PartialPoison, IRB.CreateIntToPtr(Ptr, RZPtrTy));
ConstantInt::get(IntptrTy, LocalStackSize), OrigStackBase);
}
- // This string will be parsed by the run-time (DescribeStackAddress).
+ // This string will be parsed by the run-time (DescribeAddressIfStack).
SmallString<2048> StackDescriptionStorage;
raw_svector_ostream StackDescription(StackDescriptionStorage);
- StackDescription << F.getName() << " " << AllocaVec.size() << " ";
+ StackDescription << AllocaVec.size() << " ";
// Insert poison calls for lifetime intrinsics for alloca.
bool HavePoisonedAllocas = false;
}
assert(Pos == LocalStackSize);
- // Write the Magic value and the frame description constant to the redzone.
+ // The left-most redzone has enough space for at least 4 pointers.
+ // Write the Magic value to redzone[0].
Value *BasePlus0 = IRB.CreateIntToPtr(LocalStackBase, IntptrPtrTy);
IRB.CreateStore(ConstantInt::get(IntptrTy, kCurrentStackFrameMagic),
BasePlus0);
- Value *BasePlus1 = IRB.CreateAdd(LocalStackBase,
- ConstantInt::get(IntptrTy,
- ASan.LongSize/8));
- BasePlus1 = IRB.CreateIntToPtr(BasePlus1, IntptrPtrTy);
+ // Write the frame description constant to redzone[1].
+ Value *BasePlus1 = IRB.CreateIntToPtr(
+ IRB.CreateAdd(LocalStackBase, ConstantInt::get(IntptrTy, ASan.LongSize/8)),
+ IntptrPtrTy);
GlobalVariable *StackDescriptionGlobal =
createPrivateGlobalForString(*F.getParent(), StackDescription.str());
Value *Description = IRB.CreatePointerCast(StackDescriptionGlobal,
IntptrTy);
IRB.CreateStore(Description, BasePlus1);
+ // Write the PC to redzone[2].
+ Value *BasePlus2 = IRB.CreateIntToPtr(
+ IRB.CreateAdd(LocalStackBase, ConstantInt::get(IntptrTy,
+ 2 * ASan.LongSize/8)),
+ IntptrPtrTy);
+ IRB.CreateStore(IRB.CreatePointerCast(&F, IntptrTy), BasePlus2);
// Poison the stack redzones at the entry.
Value *ShadowBase = ASan.memToShadow(LocalStackBase, IRB);