#include "llvm/ADT/StringExtras.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Dominators.h"
+#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/InstVisitor.h"
FunctionType *DFSanUnimplementedFnTy;
FunctionType *DFSanSetLabelFnTy;
FunctionType *DFSanNonzeroLabelFnTy;
+ FunctionType *DFSanVarargWrapperFnTy;
Constant *DFSanUnionFn;
Constant *DFSanCheckedUnionFn;
Constant *DFSanUnionLoadFn;
Constant *DFSanUnimplementedFn;
Constant *DFSanSetLabelFn;
Constant *DFSanNonzeroLabelFn;
+ Constant *DFSanVarargWrapperFn;
MDNode *ColdCallWeights;
DFSanABIList ABIList;
DenseMap<Value *, Function *> UnwrappedFnMap;
AttributeSet ReadOnlyNoneAttrs;
+ DenseMap<const Function *, DISubprogram> FunctionDIs;
Value *getShadowAddress(Value *Addr, Instruction *Pos);
bool isInstrumented(const Function *F);
}
FunctionType *DataFlowSanitizer::getCustomFunctionType(FunctionType *T) {
- if (T->isVarArg()) {
- // The labels are passed after all the arguments so there is no need to
- // adjust the function type.
- return T;
- }
-
llvm::SmallVector<Type *, 4> ArgTypes;
for (FunctionType::param_iterator i = T->param_begin(), e = T->param_end();
i != e; ++i) {
}
for (unsigned i = 0, e = T->getNumParams(); i != e; ++i)
ArgTypes.push_back(ShadowTy);
+ if (T->isVarArg())
+ ArgTypes.push_back(ShadowPtrTy);
Type *RetType = T->getReturnType();
if (!RetType->isVoidTy())
ArgTypes.push_back(ShadowPtrTy);
- return FunctionType::get(T->getReturnType(), ArgTypes, false);
+ return FunctionType::get(T->getReturnType(), ArgTypes, T->isVarArg());
}
bool DataFlowSanitizer::doInitialization(Module &M) {
DFSanSetLabelArgs, /*isVarArg=*/false);
DFSanNonzeroLabelFnTy = FunctionType::get(
Type::getVoidTy(*Ctx), None, /*isVarArg=*/false);
+ DFSanVarargWrapperFnTy = FunctionType::get(
+ Type::getVoidTy(*Ctx), Type::getInt8PtrTy(*Ctx), /*isVarArg=*/false);
if (GetArgTLSPtr) {
Type *ArgTLSTy = ArrayType::get(ShadowTy, 64);
AttributeSet::ReturnIndex));
BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", NewF);
- std::vector<Value *> Args;
- unsigned n = FT->getNumParams();
- for (Function::arg_iterator ai = NewF->arg_begin(); n != 0; ++ai, --n)
- Args.push_back(&*ai);
- CallInst *CI = CallInst::Create(F, Args, "", BB);
- if (FT->getReturnType()->isVoidTy())
- ReturnInst::Create(*Ctx, BB);
- else
- ReturnInst::Create(*Ctx, CI, BB);
+ if (F->isVarArg()) {
+ NewF->removeAttributes(
+ AttributeSet::FunctionIndex,
+ AttributeSet().addAttribute(*Ctx, AttributeSet::FunctionIndex,
+ "split-stack"));
+ CallInst::Create(DFSanVarargWrapperFn,
+ IRBuilder<>(BB).CreateGlobalStringPtr(F->getName()), "",
+ BB);
+ new UnreachableInst(*Ctx, BB);
+ } else {
+ std::vector<Value *> Args;
+ unsigned n = FT->getNumParams();
+ for (Function::arg_iterator ai = NewF->arg_begin(); n != 0; ++ai, --n)
+ Args.push_back(&*ai);
+ CallInst *CI = CallInst::Create(F, Args, "", BB);
+ if (FT->getReturnType()->isVoidTy())
+ ReturnInst::Create(*Ctx, BB);
+ else
+ ReturnInst::Create(*Ctx, CI, BB);
+ }
return NewF;
}
if (ABIList.isIn(M, "skip"))
return false;
+ FunctionDIs = makeSubprogramMap(M);
+
if (!GetArgTLSPtr) {
Type *ArgTLSTy = ArrayType::get(ShadowTy, 64);
ArgTLS = Mod->getOrInsertGlobal("__dfsan_arg_tls", ArgTLSTy);
}
DFSanNonzeroLabelFn =
Mod->getOrInsertFunction("__dfsan_nonzero_label", DFSanNonzeroLabelFnTy);
+ DFSanVarargWrapperFn = Mod->getOrInsertFunction("__dfsan_vararg_wrapper",
+ DFSanVarargWrapperFnTy);
std::vector<Function *> FnsToInstrument;
llvm::SmallPtrSet<Function *, 2> FnsWithNativeABI;
i != DFSanUnionLoadFn &&
i != DFSanUnimplementedFn &&
i != DFSanSetLabelFn &&
- i != DFSanNonzeroLabelFn)
+ i != DFSanNonzeroLabelFn &&
+ i != DFSanVarargWrapperFn)
FnsToInstrument.push_back(&*i);
}
Value *WrappedFnCst =
ConstantExpr::getBitCast(NewF, PointerType::getUnqual(FT));
F.replaceAllUsesWith(WrappedFnCst);
+
+ // Patch the pointer to LLVM function in debug info descriptor.
+ auto DI = FunctionDIs.find(&F);
+ if (DI != FunctionDIs.end())
+ DI->second.replaceFunction(&F);
+
UnwrappedFnMap[WrappedFnCst] = &F;
*i = NewF;
return;
}
+ // Calls to this function are synthesized in wrappers, and we shouldn't
+ // instrument them.
+ if (F == DFSF.DFS.DFSanVarargWrapperFn)
+ return;
+
assert(!(cast<FunctionType>(
CS.getCalledValue()->getType()->getPointerElementType())->isVarArg() &&
dyn_cast<InvokeInst>(CS.getInstruction())));
std::vector<Value *> Args;
CallSite::arg_iterator i = CS.arg_begin();
- for (unsigned n = CS.arg_size(); n != 0; ++i, --n) {
+ for (unsigned n = FT->getNumParams(); n != 0; ++i, --n) {
Type *T = (*i)->getType();
FunctionType *ParamFT;
if (isa<PointerType>(T) &&
}
i = CS.arg_begin();
- for (unsigned n = CS.arg_size(); n != 0; ++i, --n)
+ for (unsigned n = FT->getNumParams(); n != 0; ++i, --n)
Args.push_back(DFSF.getShadow(*i));
+ if (FT->isVarArg()) {
+ auto LabelVAAlloca =
+ new AllocaInst(ArrayType::get(DFSF.DFS.ShadowTy,
+ CS.arg_size() - FT->getNumParams()),
+ "labelva", DFSF.F->getEntryBlock().begin());
+
+ for (unsigned n = 0; i != CS.arg_end(); ++i, ++n) {
+ auto LabelVAPtr = IRB.CreateStructGEP(LabelVAAlloca, n);
+ IRB.CreateStore(DFSF.getShadow(*i), LabelVAPtr);
+ }
+
+ Args.push_back(IRB.CreateStructGEP(LabelVAAlloca, 0));
+ }
+
if (!FT->getReturnType()->isVoidTy()) {
if (!DFSF.LabelReturnAlloca) {
DFSF.LabelReturnAlloca =
Args.push_back(DFSF.LabelReturnAlloca);
}
+ for (i = CS.arg_begin() + FT->getNumParams(); i != CS.arg_end(); ++i)
+ Args.push_back(*i);
+
CallInst *CustomCI = IRB.CreateCall(CustomF, Args);
CustomCI->setCallingConv(CI->getCallingConv());
CustomCI->setAttributes(CI->getAttributes());