DataFlowSanitizer.cpp File Reference

#include "llvm/Transforms/Instrumentation/DataFlowSanitizer.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/None.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Triple.h"
#include "llvm/ADT/iterator.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/IR/Argument.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/InstVisitor.h"
#include "llvm/IR/InstrTypes.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/PassManager.h"
#include "llvm/IR/Type.h"
#include "llvm/IR/User.h"
#include "llvm/IR/Value.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/Alignment.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/SpecialCaseList.h"
#include "llvm/Support/VirtualFileSystem.h"
#include "llvm/Transforms/Instrumentation.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <iterator>
#include <memory>
#include <set>
#include <string>
#include <utility>
#include <vector>

Go to the source code of this file.

Functions
static StringRef	getGlobalTypeString (const GlobalValue &G)
static Value *	expandFromPrimitiveShadowRecursive (Value *Shadow, SmallVector< unsigned, 4 > &Indices, Type *SubShadowTy, Value *PrimitiveShadow, IRBuilder<> &IRB)
static AtomicOrdering	addAcquireOrdering (AtomicOrdering AO)
static AtomicOrdering	addReleaseOrdering (AtomicOrdering AO)
static bool	isAMustTailRetVal (Value *RetVal)
	INITIALIZE_PASS (DataFlowSanitizerLegacyPass, "dfsan", "DataFlowSanitizer: dynamic data flow analysis.", false, false) ModulePass *llvm

Variables
static const Align	ShadowTLSAlignment = Align(2)
static const Align	MinOriginAlignment = Align(4)
static const unsigned	ArgTLSSize = 800
static const unsigned	RetvalTLSSize = 800
static cl::opt< bool >	ClPreserveAlignment ("dfsan-preserve-alignment", cl::desc("respect alignment requirements provided by input IR"), cl::Hidden, cl::init(false))
static cl::list< std::string >	ClABIListFiles ("dfsan-abilist", cl::desc("File listing native ABI functions and how the pass treats them"), cl::Hidden)
static cl::opt< bool >	ClCombinePointerLabelsOnLoad ("dfsan-combine-pointer-labels-on-load", cl::desc("Combine the label of the pointer with the label of the data when " "loading from memory."), cl::Hidden, cl::init(true))
static cl::opt< bool >	ClCombinePointerLabelsOnStore ("dfsan-combine-pointer-labels-on-store", cl::desc("Combine the label of the pointer with the label of the data when " "storing in memory."), cl::Hidden, cl::init(false))
static cl::opt< bool >	ClCombineOffsetLabelsOnGEP ("dfsan-combine-offset-labels-on-gep", cl::desc("Combine the label of the offset with the label of the pointer when " "doing pointer arithmetic."), cl::Hidden, cl::init(true))
static cl::opt< bool >	ClDebugNonzeroLabels ("dfsan-debug-nonzero-labels", cl::desc("Insert calls to __dfsan_nonzero_label on observing a parameter, " "load or return with a nonzero label"), cl::Hidden)
static cl::opt< bool >	ClEventCallbacks ("dfsan-event-callbacks", cl::desc("Insert calls to __dfsan_*_callback functions on data events."), cl::Hidden, cl::init(false))
static cl::opt< bool >	ClTrackSelectControlFlow ("dfsan-track-select-control-flow", cl::desc("Propagate labels from condition values of select instructions " "to results."), cl::Hidden, cl::init(true))
static cl::opt< int >	ClInstrumentWithCallThreshold ("dfsan-instrument-with-call-threshold", cl::desc("If the function being instrumented requires more than " "this number of origin stores, use callbacks instead of " "inline checks (-1 means never use callbacks)."), cl::Hidden, cl::init(3500))
static cl::opt< int >	ClTrackOrigins ("dfsan-track-origins", cl::desc("Track origins of labels"), cl::Hidden, cl::init(0))
static const MemoryMapParams	Linux_X86_64_MemoryMapParams

Detailed Description

This file is a part of DataFlowSanitizer, a generalised dynamic data flow analysis.

Unlike other Sanitizer tools, this tool is not designed to detect a specific class of bugs on its own. Instead, it provides a generic dynamic data flow analysis framework to be used by clients to help detect application-specific issues within their own code.

The analysis is based on automatic propagation of data flow labels (also known as taint labels) through a program as it performs computation.

Argument and return value labels are passed through TLS variables __dfsan_arg_tls and __dfsan_retval_tls.

Each byte of application memory is backed by a shadow memory byte. The shadow byte can represent up to 8 labels. On Linux/x86_64, memory is then laid out as follows:

+-----------------—+ 0x800000000000 (top of memory) | application 3 | +-----------------—+ 0x700000000000 | invalid | +-----------------—+ 0x610000000000 | origin 1 | +-----------------—+ 0x600000000000 | application 2 | +-----------------—+ 0x510000000000 | shadow 1 | +-----------------—+ 0x500000000000 | invalid | +-----------------—+ 0x400000000000 | origin 3 | +-----------------—+ 0x300000000000 | shadow 3 | +-----------------—+ 0x200000000000 | origin 2 | +-----------------—+ 0x110000000000 | invalid | +-----------------—+ 0x100000000000 | shadow 2 | +-----------------—+ 0x010000000000 | application 1 | +-----------------—+ 0x000000000000

MEM_TO_SHADOW(mem) = mem ^ 0x500000000000 SHADOW_TO_ORIGIN(shadow) = shadow + 0x100000000000

For more information, please refer to the design document: http://clang.llvm.org/docs/DataFlowSanitizerDesign.html

Definition in file DataFlowSanitizer.cpp.

Function Documentation

addAcquireOrdering()

static AtomicOrdering addAcquireOrdering ( AtomicOrdering  AO )

static

Definition at line 2086 of file DataFlowSanitizer.cpp.

References llvm_unreachable, and Unordered.

addReleaseOrdering()

static AtomicOrdering addReleaseOrdering ( AtomicOrdering  AO )

static

Definition at line 2346 of file DataFlowSanitizer.cpp.

References llvm_unreachable, and Unordered.

expandFromPrimitiveShadowRecursive()

static Value* expandFromPrimitiveShadowRecursive ( Value *  Shadow, SmallVector< unsigned, 4 > &  Indices, Type *  SubShadowTy, Value *  PrimitiveShadow, IRBuilder<> &  IRB  )

static

Definition at line 867 of file DataFlowSanitizer.cpp.

References llvm::IRBuilderBase::CreateInsertValue(), llvm_unreachable, and llvm::ARM_MB::ST.

getGlobalTypeString()

static StringRef getGlobalTypeString ( const GlobalValue &  G )

static

Definition at line 235 of file DataFlowSanitizer.cpp.

References G.

INITIALIZE_PASS()

INITIALIZE_PASS	(	DataFlowSanitizerLegacyPass	,
		"dfsan"	,
		"DataFlowSanitizer: dynamic data flow analysis."	,
		false	,
		false
	)

Definition at line 3030 of file DataFlowSanitizer.cpp.

isAMustTailRetVal()

static bool isAMustTailRetVal ( Value *  RetVal )

static

Definition at line 2665 of file DataFlowSanitizer.cpp.

References I.

Variable Documentation

ArgTLSSize

const unsigned ArgTLSSize = 800

static

Definition at line 131 of file DataFlowSanitizer.cpp.

ClABIListFiles

cl::list<std::string> ClABIListFiles("dfsan-abilist", cl::desc("File listing native ABI functions and how the pass treats them"), cl::Hidden)

static

ClCombineOffsetLabelsOnGEP

cl::opt<bool> ClCombineOffsetLabelsOnGEP("dfsan-combine-offset-labels-on-gep", cl::desc( "Combine the label of the offset with the label of the pointer when " "doing pointer arithmetic."), cl::Hidden, cl::init(true))

static

ClCombinePointerLabelsOnLoad

cl::opt<bool> ClCombinePointerLabelsOnLoad("dfsan-combine-pointer-labels-on-load", cl::desc("Combine the label of the pointer with the label of the data when " "loading from memory."), cl::Hidden, cl::init(true))

static

ClCombinePointerLabelsOnStore

cl::opt<bool> ClCombinePointerLabelsOnStore("dfsan-combine-pointer-labels-on-store", cl::desc("Combine the label of the pointer with the label of the data when " "storing in memory."), cl::Hidden, cl::init(false))

static

ClDebugNonzeroLabels

cl::opt<bool> ClDebugNonzeroLabels("dfsan-debug-nonzero-labels", cl::desc("Insert calls to __dfsan_nonzero_label on observing a parameter, " "load or return with a nonzero label"), cl::Hidden)

static

ClEventCallbacks

cl::opt<bool> ClEventCallbacks("dfsan-event-callbacks", cl::desc("Insert calls to __dfsan_*_callback functions on data events."), cl::Hidden, cl::init(false))

static

ClInstrumentWithCallThreshold

cl::opt<int> ClInstrumentWithCallThreshold("dfsan-instrument-with-call-threshold", cl::desc("If the function being instrumented requires more than " "this number of origin stores, use callbacks instead of " "inline checks (-1 means never use callbacks)."), cl::Hidden, cl::init(3500))

static

ClPreserveAlignment

cl::opt<bool> ClPreserveAlignment("dfsan-preserve-alignment", cl::desc("respect alignment requirements provided by input IR"), cl::Hidden, cl::init(false))

static

ClTrackOrigins

cl::opt<int> ClTrackOrigins("dfsan-track-origins", cl::desc("Track origins of labels"), cl::Hidden, cl::init(0))

static

ClTrackSelectControlFlow

cl::opt<bool> ClTrackSelectControlFlow("dfsan-track-select-control-flow", cl::desc("Propagate labels from condition values of select instructions " "to results."), cl::Hidden, cl::init(true))

static

Linux_X86_64_MemoryMapParams

const MemoryMapParams Linux_X86_64_MemoryMapParams

static

Initial value:

= {
    0,              
    0x500000000000, 
    0,              
    0x100000000000, 
}

Definition at line 263 of file DataFlowSanitizer.cpp.

MinOriginAlignment

const Align MinOriginAlignment = Align(4)

static

Definition at line 127 of file DataFlowSanitizer.cpp.

RetvalTLSSize

const unsigned RetvalTLSSize = 800

static

Definition at line 132 of file DataFlowSanitizer.cpp.

ShadowTLSAlignment

const Align ShadowTLSAlignment = Align(2)

static

Definition at line 125 of file DataFlowSanitizer.cpp.