AddressSanitizer.cpp revision 2735cf4aa52e31b8d2de90f836c3ad991215e04e
1800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany//===-- AddressSanitizer.cpp - memory error detector ------------*- C++ -*-===// 2800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// 3800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// The LLVM Compiler Infrastructure 4800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// 5800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This file is distributed under the University of Illinois Open Source 6800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// License. See LICENSE.TXT for details. 7800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// 8800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany//===----------------------------------------------------------------------===// 9800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// 10800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This file is a part of AddressSanitizer, an address sanity checker. 11800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Details of the algorithm: 12800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// http://code.google.com/p/address-sanitizer/wiki/AddressSanitizerAlgorithm 13800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// 14800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany//===----------------------------------------------------------------------===// 15800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 16800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#define DEBUG_TYPE "asan" 17800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 18a1c45044099cf7fb4a072f1326f164706d5bb2e2Kostya Serebryany#include "FunctionBlackList.h" 1906cb8ed00696eb14d1b831921452e50ec0568ea2Chandler Carruth#include "llvm/Function.h" 2006cb8ed00696eb14d1b831921452e50ec0568ea2Chandler Carruth#include "llvm/IRBuilder.h" 2106cb8ed00696eb14d1b831921452e50ec0568ea2Chandler Carruth#include "llvm/IntrinsicInst.h" 2206cb8ed00696eb14d1b831921452e50ec0568ea2Chandler Carruth#include "llvm/LLVMContext.h" 2306cb8ed00696eb14d1b831921452e50ec0568ea2Chandler Carruth#include "llvm/Module.h" 2406cb8ed00696eb14d1b831921452e50ec0568ea2Chandler Carruth#include "llvm/Type.h" 25800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/ArrayRef.h" 26800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/OwningPtr.h" 27800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/SmallSet.h" 28800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/SmallString.h" 29800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/SmallVector.h" 30800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/StringExtras.h" 3106fdbaa9145f01a291d4981ca5120b7bdcad44c6Evgeniy Stepanov#include "llvm/ADT/Triple.h" 32800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/CommandLine.h" 33800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/DataTypes.h" 34800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/Debug.h" 35800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/raw_ostream.h" 36800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/system_error.h" 37800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Target/TargetData.h" 38800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Target/TargetMachine.h" 39800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Transforms/Instrumentation.h" 40800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Transforms/Utils/BasicBlockUtils.h" 41800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Transforms/Utils/ModuleUtils.h" 42800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 43800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include <string> 44800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include <algorithm> 45800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 46800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanyusing namespace llvm; 47800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 48800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uint64_t kDefaultShadowScale = 3; 49800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uint64_t kDefaultShadowOffset32 = 1ULL << 29; 50800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uint64_t kDefaultShadowOffset64 = 1ULL << 44; 5106fdbaa9145f01a291d4981ca5120b7bdcad44c6Evgeniy Stepanovstatic const uint64_t kDefaultShadowOffsetAndroid = 0; 52800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 53800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const size_t kMaxStackMallocSize = 1 << 16; // 64K 54800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uintptr_t kCurrentStackFrameMagic = 0x41B58AB3; 55800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uintptr_t kRetiredStackFrameMagic = 0x45E0360E; 56800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 57800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const char *kAsanModuleCtorName = "asan.module_ctor"; 587bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryanystatic const char *kAsanModuleDtorName = "asan.module_dtor"; 597bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryanystatic const int kAsanCtorAndCtorPriority = 1; 60800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const char *kAsanReportErrorTemplate = "__asan_report_"; 61800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const char *kAsanRegisterGlobalsName = "__asan_register_globals"; 627bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryanystatic const char *kAsanUnregisterGlobalsName = "__asan_unregister_globals"; 63800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const char *kAsanInitName = "__asan_init"; 6495e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryanystatic const char *kAsanHandleNoReturnName = "__asan_handle_no_return"; 65800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const char *kAsanMappingOffsetName = "__asan_mapping_offset"; 66800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const char *kAsanMappingScaleName = "__asan_mapping_scale"; 67800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const char *kAsanStackMallocName = "__asan_stack_malloc"; 68800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const char *kAsanStackFreeName = "__asan_stack_free"; 69800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 70800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const int kAsanStackLeftRedzoneMagic = 0xf1; 71800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const int kAsanStackMidRedzoneMagic = 0xf2; 72800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const int kAsanStackRightRedzoneMagic = 0xf3; 73800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const int kAsanStackPartialRedzoneMagic = 0xf4; 74800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 75c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany// Accesses sizes are powers of two: 1, 2, 4, 8, 16. 76c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanystatic const size_t kNumberOfAccessSizes = 5; 77c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 78800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Command-line flags. 79800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 80800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -f[no-]asan-reads. 81800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClInstrumentReads("asan-instrument-reads", 82800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("instrument read instructions"), cl::Hidden, cl::init(true)); 83800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClInstrumentWrites("asan-instrument-writes", 84800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("instrument write instructions"), cl::Hidden, cl::init(true)); 85e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryanystatic cl::opt<bool> ClInstrumentAtomics("asan-instrument-atomics", 86e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany cl::desc("instrument atomic instructions (rmw, cmpxchg)"), 87e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany cl::Hidden, cl::init(true)); 88c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanystatic cl::opt<bool> ClMergeCallbacks("asan-merge-callbacks", 89c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany cl::desc("merge __asan_report_ callbacks to create fewer BBs"), 90c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany cl::Hidden, cl::init(false)); 91c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany// This flag limits the number of instructions to be instrumented 92324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany// in any given BB. Normally, this should be set to unlimited (INT_MAX), 93324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany// but due to http://llvm.org/bugs/show_bug.cgi?id=12652 we temporary 94324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany// set it to 10000. 95324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryanystatic cl::opt<int> ClMaxInsnsToInstrumentPerBB("asan-max-ins-per-bb", 96324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany cl::init(10000), 97324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany cl::desc("maximal number of instructions to instrument in any given BB"), 98324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany cl::Hidden); 99800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -f[no]asan-stack. 100800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClStack("asan-stack", 101800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Handle stack memory"), cl::Hidden, cl::init(true)); 102800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -f[no]asan-use-after-return. 103800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClUseAfterReturn("asan-use-after-return", 104800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Check return-after-free"), cl::Hidden, cl::init(false)); 105800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -f[no]asan-globals. 106800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClGlobals("asan-globals", 107800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Handle global objects"), cl::Hidden, cl::init(true)); 108800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClMemIntrin("asan-memintrin", 109800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Handle memset/memcpy/memmove"), cl::Hidden, cl::init(true)); 110800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -fasan-blacklist. 111800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<std::string> ClBlackListFile("asan-blacklist", 112800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("File containing the list of functions to ignore " 113800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany "during instrumentation"), cl::Hidden); 114800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 115800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// These flags allow to change the shadow mapping. 116800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// The shadow mapping looks like 117800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Shadow = (Mem >> scale) + (1 << offset_log) 118800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClMappingScale("asan-mapping-scale", 119800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("scale of asan shadow mapping"), cl::Hidden, cl::init(0)); 120800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClMappingOffsetLog("asan-mapping-offset-log", 121800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("offset of asan shadow mapping"), cl::Hidden, cl::init(-1)); 122800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 123800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Optimization flags. Not user visible, used mostly for testing 124800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// and benchmarking the tool. 125800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClOpt("asan-opt", 126800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Optimize instrumentation"), cl::Hidden, cl::init(true)); 127800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClOptSameTemp("asan-opt-same-temp", 128800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Instrument the same temp just once"), cl::Hidden, 129800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::init(true)); 130800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClOptGlobals("asan-opt-globals", 131800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Don't instrument scalar globals"), cl::Hidden, cl::init(true)); 132800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 133800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Debug flags. 134800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClDebug("asan-debug", cl::desc("debug"), cl::Hidden, 135800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::init(0)); 136800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClDebugStack("asan-debug-stack", cl::desc("debug stack"), 137800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::Hidden, cl::init(0)); 138800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<std::string> ClDebugFunc("asan-debug-func", 139800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::Hidden, cl::desc("Debug func")); 140800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClDebugMin("asan-debug-min", cl::desc("Debug min inst"), 141800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::Hidden, cl::init(-1)); 142800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClDebugMax("asan-debug-max", cl::desc("Debug man inst"), 143800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::Hidden, cl::init(-1)); 144800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 145800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanynamespace { 146800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 147c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany/// An object of this type is created while instrumenting every function. 148c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanystruct AsanFunctionContext { 1492735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany AsanFunctionContext(Function &Function) : F(Function), CrashBlock() { } 150c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 1512735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany Function &F; 152c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // These are initially zero. If we require at least one call to 153c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // __asan_report_{read,write}{1,2,4,8,16}, an appropriate BB is created. 154c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany BasicBlock *CrashBlock[2][kNumberOfAccessSizes]; 155c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany}; 156c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 157800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany/// AddressSanitizer: instrument the code in module to find memory bugs. 158800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystruct AddressSanitizer : public ModulePass { 159800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AddressSanitizer(); 16025878042030e85c244b41bfcdfad27c32360e2ecAlexander Potapenko virtual const char *getPassName() const; 161c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany void instrumentMop(AsanFunctionContext &AFC, Instruction *I); 162c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany void instrumentAddress(AsanFunctionContext &AFC, 163c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Instruction *OrigIns, IRBuilder<> &IRB, 164800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Addr, uint32_t TypeSize, bool IsWrite); 165c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *createSlowPathCmp(IRBuilder<> &IRB, Value *AddrLong, 166c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *ShadowValue, uint32_t TypeSize); 167c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Instruction *generateCrashCode(BasicBlock *BB, Value *Addr, 1682735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany bool IsWrite, size_t AccessSizeIndex); 169c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany bool instrumentMemIntrinsic(AsanFunctionContext &AFC, MemIntrinsic *MI); 170c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany void instrumentMemIntrinsicParam(AsanFunctionContext &AFC, 171c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Instruction *OrigIns, Value *Addr, 172c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *Size, 173800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *InsertBefore, bool IsWrite); 174800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *memToShadow(Value *Shadow, IRBuilder<> &IRB); 175800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany bool handleFunction(Module &M, Function &F); 176a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany bool maybeInsertAsanInitAtFunctionEntry(Function &F); 177800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany bool poisonStackInFunction(Module &M, Function &F); 178800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany virtual bool runOnModule(Module &M); 179800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany bool insertGlobalRedzones(Module &M); 180800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany static char ID; // Pass identification, replacement for typeid 181800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 182800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany private: 183800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 184800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t getAllocaSizeInBytes(AllocaInst *AI) { 185800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *Ty = AI->getAllocatedType(); 186d8313be41031e4d768f5b38199904d4debff88cdEvgeniy Stepanov uint64_t SizeInBytes = TD->getTypeAllocSize(Ty); 187800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return SizeInBytes; 188800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 189800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t getAlignedSize(uint64_t SizeInBytes) { 190800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return ((SizeInBytes + RedzoneSize - 1) 191800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany / RedzoneSize) * RedzoneSize; 192800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 193800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t getAlignedAllocaSize(AllocaInst *AI) { 194800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t SizeInBytes = getAllocaSizeInBytes(AI); 195800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return getAlignedSize(SizeInBytes); 196800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 197800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 19855cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko Function *checkInterfaceFunction(Constant *FuncOrBitcast); 199800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany void PoisonStack(const ArrayRef<AllocaInst*> &AllocaVec, IRBuilder<> IRB, 200800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *ShadowBase, bool DoPoison); 2015a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany bool LooksLikeCodeInBug11395(Instruction *I); 202800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 203800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany LLVMContext *C; 204800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TargetData *TD; 205800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t MappingOffset; 206800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany int MappingScale; 207800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t RedzoneSize; 208800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany int LongSize; 209800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *IntptrTy; 210800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *IntptrPtrTy; 211800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Function *AsanCtorFunction; 212800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Function *AsanInitFunction; 213800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *CtorInsertBefore; 214a1c45044099cf7fb4a072f1326f164706d5bb2e2Kostya Serebryany OwningPtr<FunctionBlackList> BL; 2159db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany // This array is indexed by AccessIsWrite and log2(AccessSize). 2169db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany Function *AsanErrorCallback[2][kNumberOfAccessSizes]; 217800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany}; 218c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 219800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} // namespace 220800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 221800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanychar AddressSanitizer::ID = 0; 222800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya SerebryanyINITIALIZE_PASS(AddressSanitizer, "asan", 223800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany "AddressSanitizer: detects use-after-free and out-of-bounds bugs.", 224800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany false, false) 225800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya SerebryanyAddressSanitizer::AddressSanitizer() : ModulePass(ID) { } 226800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya SerebryanyModulePass *llvm::createAddressSanitizerPass() { 227800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return new AddressSanitizer(); 228800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 229800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 23025878042030e85c244b41bfcdfad27c32360e2ecAlexander Potapenkoconst char *AddressSanitizer::getPassName() const { 23125878042030e85c244b41bfcdfad27c32360e2ecAlexander Potapenko return "AddressSanitizer"; 23225878042030e85c244b41bfcdfad27c32360e2ecAlexander Potapenko} 23325878042030e85c244b41bfcdfad27c32360e2ecAlexander Potapenko 2342735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryanystatic size_t TypeSizeToSizeIndex(uint32_t TypeSize) { 2352735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany size_t Res = CountTrailingZeros_32(TypeSize / 8); 2362735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany assert(Res < kNumberOfAccessSizes); 2372735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany return Res; 2382735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany} 2392735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany 240800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Create a constant for Str so that we can pass it to the run-time lib. 241800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic GlobalVariable *createPrivateGlobalForString(Module &M, StringRef Str) { 24218c7f80b3e83ab584bd8572695a3cde8bafd9d3cChris Lattner Constant *StrConst = ConstantDataArray::getString(M.getContext(), Str); 243800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return new GlobalVariable(M, StrConst->getType(), true, 244800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalValue::PrivateLinkage, StrConst, ""); 245800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 246800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 247800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Split the basic block and insert an if-then code. 248800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Before: 249800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Head 25056139bc493790612ee6281630678e293be6b2eb2Kostya Serebryany// Cmp 251800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Tail 252800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// After: 253800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Head 254800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// if (Cmp) 25556139bc493790612ee6281630678e293be6b2eb2Kostya Serebryany// ThenBlock 256800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Tail 257800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// 258c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany// If ThenBlock is zero, a new block is created and its terminator is returned. 2592735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany// Otherwize 0 is returned. 260c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanystatic BranchInst *splitBlockAndInsertIfThen(Value *Cmp, 261c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany BasicBlock *ThenBlock = 0) { 26256139bc493790612ee6281630678e293be6b2eb2Kostya Serebryany Instruction *SplitBefore = cast<Instruction>(Cmp)->getNextNode(); 263800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BasicBlock *Head = SplitBefore->getParent(); 264349f14c72cbcd3c50091d20a874967aca5f2f746Chandler Carruth BasicBlock *Tail = Head->splitBasicBlock(SplitBefore); 265800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TerminatorInst *HeadOldTerm = Head->getTerminator(); 2662735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany BranchInst *CheckTerm = 0; 267c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany if (!ThenBlock) { 268c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany LLVMContext &C = Head->getParent()->getParent()->getContext(); 269c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany ThenBlock = BasicBlock::Create(C, "", Head->getParent()); 270c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany CheckTerm = BranchInst::Create(Tail, ThenBlock); 271c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany } 272349f14c72cbcd3c50091d20a874967aca5f2f746Chandler Carruth BranchInst *HeadNewTerm = 273349f14c72cbcd3c50091d20a874967aca5f2f746Chandler Carruth BranchInst::Create(/*ifTrue*/ThenBlock, /*ifFalse*/Tail, Cmp); 274349f14c72cbcd3c50091d20a874967aca5f2f746Chandler Carruth ReplaceInstWithInst(HeadOldTerm, HeadNewTerm); 275349f14c72cbcd3c50091d20a874967aca5f2f746Chandler Carruth 276349f14c72cbcd3c50091d20a874967aca5f2f746Chandler Carruth return CheckTerm; 277800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 278800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 279800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya SerebryanyValue *AddressSanitizer::memToShadow(Value *Shadow, IRBuilder<> &IRB) { 280800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Shadow >> scale 281800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Shadow = IRB.CreateLShr(Shadow, MappingScale); 282800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (MappingOffset == 0) 283800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return Shadow; 284800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // (Shadow >> scale) | offset 285800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return IRB.CreateOr(Shadow, ConstantInt::get(IntptrTy, 286800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany MappingOffset)); 287800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 288800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 289c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanyvoid AddressSanitizer::instrumentMemIntrinsicParam( 290c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany AsanFunctionContext &AFC, Instruction *OrigIns, 291800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Addr, Value *Size, Instruction *InsertBefore, bool IsWrite) { 292800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Check the first byte. 293800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany { 294800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(InsertBefore); 295c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany instrumentAddress(AFC, OrigIns, IRB, Addr, 8, IsWrite); 296800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 297800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Check the last byte. 298800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany { 299800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(InsertBefore); 300800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *SizeMinusOne = IRB.CreateSub( 301800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Size, ConstantInt::get(Size->getType(), 1)); 302800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SizeMinusOne = IRB.CreateIntCast(SizeMinusOne, IntptrTy, false); 303800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *AddrLong = IRB.CreatePointerCast(Addr, IntptrTy); 304800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *AddrPlusSizeMinisOne = IRB.CreateAdd(AddrLong, SizeMinusOne); 305c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany instrumentAddress(AFC, OrigIns, IRB, AddrPlusSizeMinisOne, 8, IsWrite); 306800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 307800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 308800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 309800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Instrument memset/memmove/memcpy 310c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanybool AddressSanitizer::instrumentMemIntrinsic(AsanFunctionContext &AFC, 311c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany MemIntrinsic *MI) { 312800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Dst = MI->getDest(); 313800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany MemTransferInst *MemTran = dyn_cast<MemTransferInst>(MI); 3142735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany Value *Src = MemTran ? MemTran->getSource() : 0; 315800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Length = MI->getLength(); 316800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 317800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Constant *ConstLength = dyn_cast<Constant>(Length); 318800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *InsertBefore = MI; 319800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ConstLength) { 320800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ConstLength->isNullValue()) return false; 321800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else { 322800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // The size is not a constant so it could be zero -- check at run-time. 323800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(InsertBefore); 324800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 325800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Cmp = IRB.CreateICmpNE(Length, 32656139bc493790612ee6281630678e293be6b2eb2Kostya Serebryany Constant::getNullValue(Length->getType())); 32756139bc493790612ee6281630678e293be6b2eb2Kostya Serebryany InsertBefore = splitBlockAndInsertIfThen(Cmp); 328800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 329800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 330c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany instrumentMemIntrinsicParam(AFC, MI, Dst, Length, InsertBefore, true); 331800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (Src) 332c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany instrumentMemIntrinsicParam(AFC, MI, Src, Length, InsertBefore, false); 333800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return true; 334800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 335800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 336e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany// If I is an interesting memory access, return the PointerOperand 337e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany// and set IsWrite. Otherwise return NULL. 338e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryanystatic Value *isInterestingMemoryAccess(Instruction *I, bool *IsWrite) { 339800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (LoadInst *LI = dyn_cast<LoadInst>(I)) { 340e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (!ClInstrumentReads) return NULL; 341e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany *IsWrite = false; 342800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return LI->getPointerOperand(); 343800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 344e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (StoreInst *SI = dyn_cast<StoreInst>(I)) { 345e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (!ClInstrumentWrites) return NULL; 346e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany *IsWrite = true; 347e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany return SI->getPointerOperand(); 348e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany } 349e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (AtomicRMWInst *RMW = dyn_cast<AtomicRMWInst>(I)) { 350e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (!ClInstrumentAtomics) return NULL; 351e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany *IsWrite = true; 352e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany return RMW->getPointerOperand(); 353e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany } 354e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (AtomicCmpXchgInst *XCHG = dyn_cast<AtomicCmpXchgInst>(I)) { 355e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (!ClInstrumentAtomics) return NULL; 356e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany *IsWrite = true; 357e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany return XCHG->getPointerOperand(); 358e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany } 359e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany return NULL; 360800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 361800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 362c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanyvoid AddressSanitizer::instrumentMop(AsanFunctionContext &AFC, Instruction *I) { 363e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany bool IsWrite; 364e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany Value *Addr = isInterestingMemoryAccess(I, &IsWrite); 365e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany assert(Addr); 366800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClOpt && ClOptGlobals && isa<GlobalVariable>(Addr)) { 367800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // We are accessing a global scalar variable. Nothing to catch here. 368800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return; 369800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 370800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *OrigPtrTy = Addr->getType(); 371800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *OrigTy = cast<PointerType>(OrigPtrTy)->getElementType(); 372800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 373800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(OrigTy->isSized()); 374800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint32_t TypeSize = TD->getTypeStoreSizeInBits(OrigTy); 375800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 376800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (TypeSize != 8 && TypeSize != 16 && 377800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TypeSize != 32 && TypeSize != 64 && TypeSize != 128) { 378800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Ignore all unusual sizes. 379800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return; 380800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 381800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 382800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(I); 383c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany instrumentAddress(AFC, I, IRB, Addr, TypeSize, IsWrite); 384800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 385800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 38655cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko// Validate the result of Module::getOrInsertFunction called for an interface 38755cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko// function of AddressSanitizer. If the instrumented module defines a function 38855cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko// with the same name, their prototypes must match, otherwise 38955cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko// getOrInsertFunction returns a bitcast. 39055cabae685991ac6bc6d96b14e2139f64a0c9967Alexander PotapenkoFunction *AddressSanitizer::checkInterfaceFunction(Constant *FuncOrBitcast) { 39155cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko if (isa<Function>(FuncOrBitcast)) return cast<Function>(FuncOrBitcast); 39255cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko FuncOrBitcast->dump(); 39355cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko report_fatal_error("trying to redefine an AddressSanitizer " 39455cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko "interface function"); 39555cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko} 39655cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko 397800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya SerebryanyInstruction *AddressSanitizer::generateCrashCode( 3982735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany BasicBlock *BB, Value *Addr, bool IsWrite, size_t AccessSizeIndex) { 399c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany IRBuilder<> IRB(BB->getFirstNonPHI()); 4009db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany CallInst *Call = IRB.CreateCall(AsanErrorCallback[IsWrite][AccessSizeIndex], 4019db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany Addr); 4023c7faae346f548c55cad86d82a2e242443001f23Kostya Serebryany Call->setDoesNotReturn(); 4033c7faae346f548c55cad86d82a2e242443001f23Kostya Serebryany return Call; 404800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 405800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 4062735cf4aa52e31b8d2de90f836c3ad991215e04eKostya SerebryanyValue *AddressSanitizer::createSlowPathCmp(IRBuilder<> &IRB, Value *AddrLong, 407c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *ShadowValue, 408c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany uint32_t TypeSize) { 409c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany size_t Granularity = 1 << MappingScale; 410c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // Addr & (Granularity - 1) 411c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *LastAccessedByte = IRB.CreateAnd( 412c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany AddrLong, ConstantInt::get(IntptrTy, Granularity - 1)); 413c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // (Addr & (Granularity - 1)) + size - 1 414c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany if (TypeSize / 8 > 1) 415c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany LastAccessedByte = IRB.CreateAdd( 416c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany LastAccessedByte, ConstantInt::get(IntptrTy, TypeSize / 8 - 1)); 417c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // (uint8_t) ((Addr & (Granularity-1)) + size - 1) 418c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany LastAccessedByte = IRB.CreateIntCast( 419c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany LastAccessedByte, IRB.getInt8Ty(), false); 420c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // ((uint8_t) ((Addr & (Granularity-1)) + size - 1)) >= ShadowValue 421c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany return IRB.CreateICmpSGE(LastAccessedByte, ShadowValue); 422c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany} 423c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 424c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanyvoid AddressSanitizer::instrumentAddress(AsanFunctionContext &AFC, 425c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Instruction *OrigIns, 426800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> &IRB, Value *Addr, 427800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint32_t TypeSize, bool IsWrite) { 428800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *AddrLong = IRB.CreatePointerCast(Addr, IntptrTy); 429800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 430800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *ShadowTy = IntegerType::get( 431800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany *C, std::max(8U, TypeSize >> MappingScale)); 432800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *ShadowPtrTy = PointerType::get(ShadowTy, 0); 433800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *ShadowPtr = memToShadow(AddrLong, IRB); 434800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *CmpVal = Constant::getNullValue(ShadowTy); 435800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *ShadowValue = IRB.CreateLoad( 436800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateIntToPtr(ShadowPtr, ShadowPtrTy)); 437800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 438800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Cmp = IRB.CreateICmpNE(ShadowValue, CmpVal); 439800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 4402735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany BasicBlock *CrashBlock = 0; 441c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany if (ClMergeCallbacks) { 4422735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany BasicBlock **Cached = 4432735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany &AFC.CrashBlock[IsWrite][TypeSizeToSizeIndex(TypeSize)]; 4442735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany if (!*Cached) { 4452735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany BasicBlock *BB = BasicBlock::Create(*C, "crash_bb", &AFC.F); 4462735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany new UnreachableInst(*C, BB); 4472735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany *Cached = BB; 4482735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany } 4492735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany CrashBlock = *Cached; 450c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany } else { 4512735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany CrashBlock = BasicBlock::Create(*C, "crash_bb", &AFC.F); 452c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany new UnreachableInst(*C, CrashBlock); 4532735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany size_t AccessSizeIndex = TypeSizeToSizeIndex(TypeSize); 454c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Instruction *Crash = 4552735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany generateCrashCode(CrashBlock, AddrLong, IsWrite, AccessSizeIndex); 456c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Crash->setDebugLoc(OrigIns->getDebugLoc()); 457c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany } 458800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 459800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t Granularity = 1 << MappingScale; 460800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (TypeSize < 8 * Granularity) { 461c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Instruction *CheckTerm = splitBlockAndInsertIfThen(Cmp); 462c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany IRB.SetInsertPoint(CheckTerm); 463c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *Cmp2 = createSlowPathCmp(IRB, AddrLong, ShadowValue, TypeSize); 464c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany splitBlockAndInsertIfThen(Cmp2, CrashBlock); 465c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany } else { 466c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany splitBlockAndInsertIfThen(Cmp, CrashBlock); 467800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 468800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 469800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 470800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This function replaces all global variables with new variables that have 471800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// trailing redzones. It also creates a function that poisons 472800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// redzones and inserts this function into llvm.global_ctors. 473800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanybool AddressSanitizer::insertGlobalRedzones(Module &M) { 474800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallVector<GlobalVariable *, 16> GlobalsToChange; 475800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 476800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (Module::GlobalListType::iterator G = M.getGlobalList().begin(), 477800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany E = M.getGlobalList().end(); G != E; ++G) { 478800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *Ty = cast<PointerType>(G->getType())->getElementType(); 479800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany DEBUG(dbgs() << "GLOBAL: " << *G); 480800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 481800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!Ty->isSized()) continue; 482800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!G->hasInitializer()) continue; 4837cf2a04361e8613264498e50babe52d65c070473Kostya Serebryany // Touch only those globals that will not be defined in other modules. 4847cf2a04361e8613264498e50babe52d65c070473Kostya Serebryany // Don't handle ODR type linkages since other modules may be built w/o asan. 4852e7fb2f73641f1f1ca385fe7777075945bf4ca24Kostya Serebryany if (G->getLinkage() != GlobalVariable::ExternalLinkage && 4862e7fb2f73641f1f1ca385fe7777075945bf4ca24Kostya Serebryany G->getLinkage() != GlobalVariable::PrivateLinkage && 4872e7fb2f73641f1f1ca385fe7777075945bf4ca24Kostya Serebryany G->getLinkage() != GlobalVariable::InternalLinkage) 488800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany continue; 489d2703dec271d82c8c9d22afb835c07730fd25d47Kostya Serebryany // Two problems with thread-locals: 490d2703dec271d82c8c9d22afb835c07730fd25d47Kostya Serebryany // - The address of the main thread's copy can't be computed at link-time. 491d2703dec271d82c8c9d22afb835c07730fd25d47Kostya Serebryany // - Need to poison all copies, not just the main thread's one. 492d2703dec271d82c8c9d22afb835c07730fd25d47Kostya Serebryany if (G->isThreadLocal()) 493d2703dec271d82c8c9d22afb835c07730fd25d47Kostya Serebryany continue; 494800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // For now, just ignore this Alloca if the alignment is large. 495800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (G->getAlignment() > RedzoneSize) continue; 496800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 497800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Ignore all the globals with the names starting with "\01L_OBJC_". 498800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Many of those are put into the .cstring section. The linker compresses 499800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // that section by removing the spare \0s after the string terminator, so 500800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // our redzones get broken. 501800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if ((G->getName().find("\01L_OBJC_") == 0) || 502800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany (G->getName().find("\01l_OBJC_") == 0)) { 503800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany DEBUG(dbgs() << "Ignoring \\01L_OBJC_* global: " << *G); 504800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany continue; 505800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 506800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 507800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (G->hasSection()) { 508800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StringRef Section(G->getSection()); 5098375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // Ignore the globals from the __OBJC section. The ObjC runtime assumes 5108375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // those conform to /usr/lib/objc/runtime.h, so we can't add redzones to 5118375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // them. 512800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if ((Section.find("__OBJC,") == 0) || 513800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany (Section.find("__DATA, __objc_") == 0)) { 514800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany DEBUG(dbgs() << "Ignoring ObjC runtime global: " << *G); 515800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany continue; 516800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 5178375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // See http://code.google.com/p/address-sanitizer/issues/detail?id=32 5188375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // Constant CFString instances are compiled in the following way: 5198375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // -- the string buffer is emitted into 5208375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // __TEXT,__cstring,cstring_literals 5218375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // -- the constant NSConstantString structure referencing that buffer 5228375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // is placed into __DATA,__cfstring 5238375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // Therefore there's no point in placing redzones into __DATA,__cfstring. 5248375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko // Moreover, it causes the linker to crash on OS X 10.7 5258375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko if (Section.find("__DATA,__cfstring") == 0) { 5268375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko DEBUG(dbgs() << "Ignoring CFString: " << *G); 5278375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko continue; 5288375bc923638299410e75e8f668524fc1aa113bdAlexander Potapenko } 529800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 530800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 531800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalsToChange.push_back(G); 532800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 533800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 534800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t n = GlobalsToChange.size(); 535800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (n == 0) return false; 536800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 537800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // A global is described by a structure 538800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // size_t beg; 539800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // size_t size; 540800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // size_t size_with_redzone; 541800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // const char *name; 542800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // We initialize an array of such structures and pass it to a run-time call. 543800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StructType *GlobalStructTy = StructType::get(IntptrTy, IntptrTy, 544800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IntptrTy, IntptrTy, NULL); 545800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallVector<Constant *, 16> Initializers(n); 546800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 547800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(CtorInsertBefore); 548800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 549800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0; i < n; i++) { 550800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalVariable *G = GlobalsToChange[i]; 551800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany PointerType *PtrTy = cast<PointerType>(G->getType()); 552800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *Ty = PtrTy->getElementType(); 553208a4ff2b56f453910bb817540f34b8169f7702aKostya Serebryany uint64_t SizeInBytes = TD->getTypeAllocSize(Ty); 554800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t RightRedzoneSize = RedzoneSize + 555800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany (RedzoneSize - (SizeInBytes % RedzoneSize)); 556800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *RightRedZoneTy = ArrayType::get(IRB.getInt8Ty(), RightRedzoneSize); 557800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 558800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StructType *NewTy = StructType::get(Ty, RightRedZoneTy, NULL); 559800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Constant *NewInitializer = ConstantStruct::get( 560800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NewTy, G->getInitializer(), 561800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Constant::getNullValue(RightRedZoneTy), NULL); 562800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 563a4b2b1d8fbb84b0b6fac5abce21a2a5c5e907282Kostya Serebryany SmallString<2048> DescriptionOfGlobal = G->getName(); 564a4b2b1d8fbb84b0b6fac5abce21a2a5c5e907282Kostya Serebryany DescriptionOfGlobal += " ("; 565a4b2b1d8fbb84b0b6fac5abce21a2a5c5e907282Kostya Serebryany DescriptionOfGlobal += M.getModuleIdentifier(); 566a4b2b1d8fbb84b0b6fac5abce21a2a5c5e907282Kostya Serebryany DescriptionOfGlobal += ")"; 567a4b2b1d8fbb84b0b6fac5abce21a2a5c5e907282Kostya Serebryany GlobalVariable *Name = createPrivateGlobalForString(M, DescriptionOfGlobal); 568800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 569800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Create a new global variable with enough space for a redzone. 570800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalVariable *NewGlobal = new GlobalVariable( 571800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany M, NewTy, G->isConstant(), G->getLinkage(), 572ce718ff9f42c7da092eaa01dd0242e8d5ba84713Hans Wennborg NewInitializer, "", G, G->getThreadLocalMode()); 573800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NewGlobal->copyAttributesFrom(G); 574800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NewGlobal->setAlignment(RedzoneSize); 575800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 576800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Indices2[2]; 577800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Indices2[0] = IRB.getInt32(0); 578800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Indices2[1] = IRB.getInt32(0); 579800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 580800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany G->replaceAllUsesWith( 581f1639abf1aaba1448f719f595156cd0f4cd560ccKostya Serebryany ConstantExpr::getGetElementPtr(NewGlobal, Indices2, true)); 582800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NewGlobal->takeName(G); 583800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany G->eraseFromParent(); 584800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 585800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Initializers[i] = ConstantStruct::get( 586800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalStructTy, 587800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantExpr::getPointerCast(NewGlobal, IntptrTy), 588800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, SizeInBytes), 589800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, SizeInBytes + RightRedzoneSize), 590800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantExpr::getPointerCast(Name, IntptrTy), 591800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NULL); 592800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany DEBUG(dbgs() << "NEW GLOBAL:\n" << *NewGlobal); 593800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 594800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 595800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ArrayType *ArrayOfGlobalStructTy = ArrayType::get(GlobalStructTy, n); 596800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalVariable *AllGlobals = new GlobalVariable( 597800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany M, ArrayOfGlobalStructTy, false, GlobalVariable::PrivateLinkage, 598800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantArray::get(ArrayOfGlobalStructTy, Initializers), ""); 599800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 60055cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko Function *AsanRegisterGlobals = checkInterfaceFunction(M.getOrInsertFunction( 601800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany kAsanRegisterGlobalsName, IRB.getVoidTy(), IntptrTy, IntptrTy, NULL)); 602800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AsanRegisterGlobals->setLinkage(Function::ExternalLinkage); 603800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 604800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateCall2(AsanRegisterGlobals, 605800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreatePointerCast(AllGlobals, IntptrTy), 606800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, n)); 607800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 6087bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany // We also need to unregister globals at the end, e.g. when a shared library 6097bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany // gets closed. 6107bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany Function *AsanDtorFunction = Function::Create( 6117bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany FunctionType::get(Type::getVoidTy(*C), false), 6127bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany GlobalValue::InternalLinkage, kAsanModuleDtorName, &M); 6137bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany BasicBlock *AsanDtorBB = BasicBlock::Create(*C, "", AsanDtorFunction); 6147bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany IRBuilder<> IRB_Dtor(ReturnInst::Create(*C, AsanDtorBB)); 61555cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko Function *AsanUnregisterGlobals = 61655cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko checkInterfaceFunction(M.getOrInsertFunction( 61755cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko kAsanUnregisterGlobalsName, 61855cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko IRB.getVoidTy(), IntptrTy, IntptrTy, NULL)); 6197bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany AsanUnregisterGlobals->setLinkage(Function::ExternalLinkage); 6207bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany 6217bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany IRB_Dtor.CreateCall2(AsanUnregisterGlobals, 6227bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany IRB.CreatePointerCast(AllGlobals, IntptrTy), 6237bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany ConstantInt::get(IntptrTy, n)); 6247bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany appendToGlobalDtors(M, AsanDtorFunction, kAsanCtorAndCtorPriority); 6257bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany 626800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany DEBUG(dbgs() << M); 627800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return true; 628800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 629800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 630800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// virtual 631800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanybool AddressSanitizer::runOnModule(Module &M) { 632800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Initialize the private fields. No one has accessed them before. 633800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TD = getAnalysisIfAvailable<TargetData>(); 634800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!TD) 635800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return false; 636a1c45044099cf7fb4a072f1326f164706d5bb2e2Kostya Serebryany BL.reset(new FunctionBlackList(ClBlackListFile)); 637800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 638800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany C = &(M.getContext()); 639800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany LongSize = TD->getPointerSizeInBits(); 640800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IntptrTy = Type::getIntNTy(*C, LongSize); 641800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IntptrPtrTy = PointerType::get(IntptrTy, 0); 642800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 643800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AsanCtorFunction = Function::Create( 644800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany FunctionType::get(Type::getVoidTy(*C), false), 645800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalValue::InternalLinkage, kAsanModuleCtorName, &M); 646800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BasicBlock *AsanCtorBB = BasicBlock::Create(*C, "", AsanCtorFunction); 647800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany CtorInsertBefore = ReturnInst::Create(*C, AsanCtorBB); 648800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 649800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // call __asan_init in the module ctor. 650800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(CtorInsertBefore); 65155cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko AsanInitFunction = checkInterfaceFunction( 652800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany M.getOrInsertFunction(kAsanInitName, IRB.getVoidTy(), NULL)); 653800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AsanInitFunction->setLinkage(Function::ExternalLinkage); 654800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateCall(AsanInitFunction); 655800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 6569db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany // Create __asan_report* callbacks. 6579db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany for (size_t AccessIsWrite = 0; AccessIsWrite <= 1; AccessIsWrite++) { 6589db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany for (size_t AccessSizeIndex = 0; AccessSizeIndex < kNumberOfAccessSizes; 6599db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany AccessSizeIndex++) { 6609db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany // IsWrite and TypeSize are encoded in the function name. 6619db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany std::string FunctionName = std::string(kAsanReportErrorTemplate) + 6629db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany (AccessIsWrite ? "store" : "load") + itostr(1 << AccessSizeIndex); 6639db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany AsanErrorCallback[AccessIsWrite][AccessSizeIndex] = cast<Function>( 6649db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany M.getOrInsertFunction(FunctionName, IRB.getVoidTy(), IntptrTy, NULL)); 6659db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany } 6669db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany } 6679db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany 66806fdbaa9145f01a291d4981ca5120b7bdcad44c6Evgeniy Stepanov llvm::Triple targetTriple(M.getTargetTriple()); 66906fdbaa9145f01a291d4981ca5120b7bdcad44c6Evgeniy Stepanov bool isAndroid = targetTriple.getEnvironment() == llvm::Triple::ANDROIDEABI; 67006fdbaa9145f01a291d4981ca5120b7bdcad44c6Evgeniy Stepanov 67106fdbaa9145f01a291d4981ca5120b7bdcad44c6Evgeniy Stepanov MappingOffset = isAndroid ? kDefaultShadowOffsetAndroid : 67206fdbaa9145f01a291d4981ca5120b7bdcad44c6Evgeniy Stepanov (LongSize == 32 ? kDefaultShadowOffset32 : kDefaultShadowOffset64); 673800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClMappingOffsetLog >= 0) { 674800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClMappingOffsetLog == 0) { 675800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // special case 676800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany MappingOffset = 0; 677800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else { 678800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany MappingOffset = 1ULL << ClMappingOffsetLog; 679800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 680800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 681800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany MappingScale = kDefaultShadowScale; 682800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClMappingScale) { 683800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany MappingScale = ClMappingScale; 684800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 685800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Redzone used for stack and globals is at least 32 bytes. 686800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // For scales 6 and 7, the redzone has to be 64 and 128 bytes respectively. 687800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany RedzoneSize = std::max(32, (int)(1 << MappingScale)); 688800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 689800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany bool Res = false; 690800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 691800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClGlobals) 692800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Res |= insertGlobalRedzones(M); 693800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 6948c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany if (ClMappingOffsetLog >= 0) { 6958c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany // Tell the run-time the current values of mapping offset and scale. 6968c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany GlobalValue *asan_mapping_offset = 6978c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany new GlobalVariable(M, IntptrTy, true, GlobalValue::LinkOnceODRLinkage, 6988c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany ConstantInt::get(IntptrTy, MappingOffset), 6998c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany kAsanMappingOffsetName); 7008c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany // Read the global, otherwise it may be optimized away. 7018c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany IRB.CreateLoad(asan_mapping_offset, true); 7028c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany } 7038c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany if (ClMappingScale) { 7048c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany GlobalValue *asan_mapping_scale = 7058c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany new GlobalVariable(M, IntptrTy, true, GlobalValue::LinkOnceODRLinkage, 7068c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany ConstantInt::get(IntptrTy, MappingScale), 7078c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany kAsanMappingScaleName); 7088c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany // Read the global, otherwise it may be optimized away. 7098c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany IRB.CreateLoad(asan_mapping_scale, true); 7108c0134a77615b66f57250f0662bc899e4574551eKostya Serebryany } 711800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 712800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 713800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) { 714800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (F->isDeclaration()) continue; 715800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Res |= handleFunction(M, *F); 716800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 717800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 7187bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany appendToGlobalCtors(M, AsanCtorFunction, kAsanCtorAndCtorPriority); 7199b02741d2284d9516a59666c211fe1f57e8803adKostya Serebryany 720800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return Res; 721800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 722800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 723a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryanybool AddressSanitizer::maybeInsertAsanInitAtFunctionEntry(Function &F) { 724a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // For each NSObject descendant having a +load method, this method is invoked 725a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // by the ObjC runtime before any of the static constructors is called. 726a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // Therefore we need to instrument such methods with a call to __asan_init 727a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // at the beginning in order to initialize our runtime before any access to 728a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // the shadow memory. 729a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // We cannot just ignore these methods, because they may call other 730a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // instrumented functions. 731a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany if (F.getName().find(" load]") != std::string::npos) { 732a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany IRBuilder<> IRB(F.begin()->begin()); 733a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany IRB.CreateCall(AsanInitFunction); 734a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany return true; 735a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany } 736a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany return false; 737a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany} 738a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany 739800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanybool AddressSanitizer::handleFunction(Module &M, Function &F) { 740800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (BL->isIn(F)) return false; 741800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (&F == AsanCtorFunction) return false; 742a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany 743a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // If needed, insert __asan_init before checking for AddressSafety attr. 744a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany maybeInsertAsanInitAtFunctionEntry(F); 745a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany 7460307b9a88574d7e54459181afaa656ac92971847Kostya Serebryany if (!F.hasFnAttr(Attribute::AddressSafety)) return false; 747800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 748800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!ClDebugFunc.empty() && ClDebugFunc != F.getName()) 749800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return false; 750800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // We want to instrument every address only once per basic block 751800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // (unless there are calls between uses). 752800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallSet<Value*, 16> TempsToInstrument; 753800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallVector<Instruction*, 16> ToInstrument; 75495e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany SmallVector<Instruction*, 8> NoReturnCalls; 755e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany bool IsWrite; 756800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 757800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Fill the set of memory operations to instrument. 758800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (Function::iterator FI = F.begin(), FE = F.end(); 759800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany FI != FE; ++FI) { 760800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TempsToInstrument.clear(); 761324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany int NumInsnsPerBB = 0; 762800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); 763800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BI != BE; ++BI) { 764bcb55ce3862bbbedac4e09d7099c9e0efc434e4bKostya Serebryany if (LooksLikeCodeInBug11395(BI)) return false; 765e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (Value *Addr = isInterestingMemoryAccess(BI, &IsWrite)) { 766800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClOpt && ClOptSameTemp) { 767800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!TempsToInstrument.insert(Addr)) 768800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany continue; // We've seen this temp in the current BB. 769800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 770800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else if (isa<MemIntrinsic>(BI) && ClMemIntrin) { 771800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // ok, take it. 772800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else { 77395e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany if (CallInst *CI = dyn_cast<CallInst>(BI)) { 774800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // A call inside BB. 775800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TempsToInstrument.clear(); 77695e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany if (CI->doesNotReturn()) { 77795e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany NoReturnCalls.push_back(CI); 77895e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany } 779800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 780800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany continue; 781800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 782800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ToInstrument.push_back(BI); 783324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany NumInsnsPerBB++; 784324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany if (NumInsnsPerBB >= ClMaxInsnsToInstrumentPerBB) 785324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany break; 786800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 787800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 788800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 7892735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany AsanFunctionContext AFC(F); 790c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 791800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Instrument. 792800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany int NumInstrumented = 0; 793800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0, n = ToInstrument.size(); i != n; i++) { 794800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *Inst = ToInstrument[i]; 795800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClDebugMin < 0 || ClDebugMax < 0 || 796800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany (NumInstrumented >= ClDebugMin && NumInstrumented <= ClDebugMax)) { 797e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (isInterestingMemoryAccess(Inst, &IsWrite)) 798c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany instrumentMop(AFC, Inst); 799800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany else 800c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany instrumentMemIntrinsic(AFC, cast<MemIntrinsic>(Inst)); 801800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 802800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NumInstrumented++; 803800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 804800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 8052735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany if (NumInstrumented) { 8062735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany for (size_t IsWrite = 0; IsWrite <= 1; IsWrite++) { 8072735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany for (size_t AccessSizeIndex = 0; AccessSizeIndex < kNumberOfAccessSizes; 8082735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany AccessSizeIndex++) { 8092735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany BasicBlock *BB = AFC.CrashBlock[IsWrite][AccessSizeIndex]; 8102735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany if (!BB) continue; 8112735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany generateCrashCode(BB, ConstantInt::get(IntptrTy, 0), 8122735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany IsWrite, AccessSizeIndex); 8132735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany } 8142735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany } 8152735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany } 8162735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany 817800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany DEBUG(dbgs() << F); 818800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 819800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany bool ChangedStack = poisonStackInFunction(M, F); 82095e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany 82195e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany // We must unpoison the stack before every NoReturn call (throw, _exit, etc). 82295e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany // See e.g. http://code.google.com/p/address-sanitizer/issues/detail?id=37 82395e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany for (size_t i = 0, n = NoReturnCalls.size(); i != n; i++) { 82495e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany Instruction *CI = NoReturnCalls[i]; 82595e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany IRBuilder<> IRB(CI); 82695e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany IRB.CreateCall(M.getOrInsertFunction(kAsanHandleNoReturnName, 82795e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany IRB.getVoidTy(), NULL)); 82895e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany } 82995e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany 83095e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany return NumInstrumented > 0 || ChangedStack || !NoReturnCalls.empty(); 831800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 832800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 833800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic uint64_t ValueForPoison(uint64_t PoisonByte, size_t ShadowRedzoneSize) { 834800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ShadowRedzoneSize == 1) return PoisonByte; 835800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ShadowRedzoneSize == 2) return (PoisonByte << 8) + PoisonByte; 836800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ShadowRedzoneSize == 4) 837800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return (PoisonByte << 24) + (PoisonByte << 16) + 838800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany (PoisonByte << 8) + (PoisonByte); 839858143816d43e58b17bfd11cb1b57afbd7f0f893Craig Topper llvm_unreachable("ShadowRedzoneSize is either 1, 2 or 4"); 840800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 841800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 842800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic void PoisonShadowPartialRightRedzone(uint8_t *Shadow, 843800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t Size, 844800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t RedzoneSize, 845800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t ShadowGranularity, 846800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint8_t Magic) { 847800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0; i < RedzoneSize; 848800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany i+= ShadowGranularity, Shadow++) { 849800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (i + ShadowGranularity <= Size) { 850800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany *Shadow = 0; // fully addressable 851800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else if (i >= Size) { 852800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany *Shadow = Magic; // unaddressable 853800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else { 854800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany *Shadow = Size - i; // first Size-i bytes are addressable 855800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 856800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 857800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 858800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 859800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanyvoid AddressSanitizer::PoisonStack(const ArrayRef<AllocaInst*> &AllocaVec, 860800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB, 861800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *ShadowBase, bool DoPoison) { 862800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t ShadowRZSize = RedzoneSize >> MappingScale; 863800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(ShadowRZSize >= 1 && ShadowRZSize <= 4); 864800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *RZTy = Type::getIntNTy(*C, ShadowRZSize * 8); 865800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *RZPtrTy = PointerType::get(RZTy, 0); 866800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 867800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *PoisonLeft = ConstantInt::get(RZTy, 868800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ValueForPoison(DoPoison ? kAsanStackLeftRedzoneMagic : 0LL, ShadowRZSize)); 869800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *PoisonMid = ConstantInt::get(RZTy, 870800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ValueForPoison(DoPoison ? kAsanStackMidRedzoneMagic : 0LL, ShadowRZSize)); 871800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *PoisonRight = ConstantInt::get(RZTy, 872800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ValueForPoison(DoPoison ? kAsanStackRightRedzoneMagic : 0LL, ShadowRZSize)); 873800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 874800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // poison the first red zone. 875800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(PoisonLeft, IRB.CreateIntToPtr(ShadowBase, RZPtrTy)); 876800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 877800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // poison all other red zones. 878800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t Pos = RedzoneSize; 879800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0, n = AllocaVec.size(); i < n; i++) { 880800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AllocaInst *AI = AllocaVec[i]; 881800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t SizeInBytes = getAllocaSizeInBytes(AI); 882800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t AlignedSize = getAlignedAllocaSize(AI); 883800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(AlignedSize - SizeInBytes < RedzoneSize); 884800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Ptr = NULL; 885800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 886800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Pos += AlignedSize; 887800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 888800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(ShadowBase->getType() == IntptrTy); 889800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (SizeInBytes < AlignedSize) { 890800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Poison the partial redzone at right 891800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Ptr = IRB.CreateAdd( 892800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ShadowBase, ConstantInt::get(IntptrTy, 893800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany (Pos >> MappingScale) - ShadowRZSize)); 894800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t AddressableBytes = RedzoneSize - (AlignedSize - SizeInBytes); 895800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint32_t Poison = 0; 896800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (DoPoison) { 897800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany PoisonShadowPartialRightRedzone((uint8_t*)&Poison, AddressableBytes, 898800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany RedzoneSize, 899800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1ULL << MappingScale, 900800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany kAsanStackPartialRedzoneMagic); 901800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 902800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *PartialPoison = ConstantInt::get(RZTy, Poison); 903800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(PartialPoison, IRB.CreateIntToPtr(Ptr, RZPtrTy)); 904800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 905800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 906800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Poison the full redzone at right. 907800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Ptr = IRB.CreateAdd(ShadowBase, 908800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, Pos >> MappingScale)); 909800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Poison = i == AllocaVec.size() - 1 ? PoisonRight : PoisonMid; 910800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(Poison, IRB.CreateIntToPtr(Ptr, RZPtrTy)); 911800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 912800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Pos += RedzoneSize; 913800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 914800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 915800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 9165a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany// Workaround for bug 11395: we don't want to instrument stack in functions 9175a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany// with large assembly blobs (32-bit only), otherwise reg alloc may crash. 918d2703dec271d82c8c9d22afb835c07730fd25d47Kostya Serebryany// FIXME: remove once the bug 11395 is fixed. 9195a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryanybool AddressSanitizer::LooksLikeCodeInBug11395(Instruction *I) { 9205a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany if (LongSize != 32) return false; 9215a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany CallInst *CI = dyn_cast<CallInst>(I); 9225a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany if (!CI || !CI->isInlineAsm()) return false; 9235a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany if (CI->getNumArgOperands() <= 5) return false; 9245a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany // We have inline assembly with quite a few arguments. 9255a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany return true; 9265a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany} 9275a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany 928800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Find all static Alloca instructions and put 929800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// poisoned red zones around all of them. 930800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Then unpoison everything back before the function returns. 931800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// 932800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Stack poisoning does not play well with exception handling. 933800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// When an exception is thrown, we essentially bypass the code 934800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// that unpoisones the stack. This is why the run-time library has 935800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// to intercept __cxa_throw (as well as longjmp, etc) and unpoison the entire 936800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// stack in the interceptor. This however does not work inside the 937800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// actual function which catches the exception. Most likely because the 938800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// compiler hoists the load of the shadow value somewhere too high. 939800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This causes asan to report a non-existing bug on 453.povray. 940800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// It sounds like an LLVM bug. 941800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanybool AddressSanitizer::poisonStackInFunction(Module &M, Function &F) { 942800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!ClStack) return false; 943800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallVector<AllocaInst*, 16> AllocaVec; 944800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallVector<Instruction*, 8> RetVec; 945800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t TotalSize = 0; 946800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 947800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Filter out Alloca instructions we want (and can) handle. 948800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Collect Ret instructions. 949800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (Function::iterator FI = F.begin(), FE = F.end(); 950800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany FI != FE; ++FI) { 951800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BasicBlock &BB = *FI; 952800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (BasicBlock::iterator BI = BB.begin(), BE = BB.end(); 953800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BI != BE; ++BI) { 954800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (isa<ReturnInst>(BI)) { 955800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany RetVec.push_back(BI); 956800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany continue; 957800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 958800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 959800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AllocaInst *AI = dyn_cast<AllocaInst>(BI); 960800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!AI) continue; 961800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (AI->isArrayAllocation()) continue; 962800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!AI->isStaticAlloca()) continue; 963800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!AI->getAllocatedType()->isSized()) continue; 964800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (AI->getAlignment() > RedzoneSize) continue; 965800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AllocaVec.push_back(AI); 966800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t AlignedSize = getAlignedAllocaSize(AI); 967800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TotalSize += AlignedSize; 968800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 969800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 970800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 971800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (AllocaVec.empty()) return false; 972800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 973800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t LocalStackSize = TotalSize + (AllocaVec.size() + 1) * RedzoneSize; 974800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 975800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany bool DoStackMalloc = ClUseAfterReturn 976800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany && LocalStackSize <= kMaxStackMallocSize; 977800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 978800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *InsBefore = AllocaVec[0]; 979800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(InsBefore); 980800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 981800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 982800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *ByteArrayTy = ArrayType::get(IRB.getInt8Ty(), LocalStackSize); 983800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AllocaInst *MyAlloca = 984800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany new AllocaInst(ByteArrayTy, "MyAlloca", InsBefore); 985800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany MyAlloca->setAlignment(RedzoneSize); 986800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(MyAlloca->isStaticAlloca()); 987800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *OrigStackBase = IRB.CreatePointerCast(MyAlloca, IntptrTy); 988800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *LocalStackBase = OrigStackBase; 989800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 990800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (DoStackMalloc) { 991800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *AsanStackMallocFunc = M.getOrInsertFunction( 992800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany kAsanStackMallocName, IntptrTy, IntptrTy, IntptrTy, NULL); 993800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany LocalStackBase = IRB.CreateCall2(AsanStackMallocFunc, 994800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, LocalStackSize), OrigStackBase); 995800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 996800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 997800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // This string will be parsed by the run-time (DescribeStackAddress). 998800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallString<2048> StackDescriptionStorage; 999800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany raw_svector_ostream StackDescription(StackDescriptionStorage); 1000800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StackDescription << F.getName() << " " << AllocaVec.size() << " "; 1001800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1002800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t Pos = RedzoneSize; 1003800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Replace Alloca instructions with base+offset. 1004800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0, n = AllocaVec.size(); i < n; i++) { 1005800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AllocaInst *AI = AllocaVec[i]; 1006800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t SizeInBytes = getAllocaSizeInBytes(AI); 1007800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StringRef Name = AI->getName(); 1008800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StackDescription << Pos << " " << SizeInBytes << " " 1009800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany << Name.size() << " " << Name << " "; 1010800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t AlignedSize = getAlignedAllocaSize(AI); 1011800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert((AlignedSize % RedzoneSize) == 0); 1012800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AI->replaceAllUsesWith( 1013800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateIntToPtr( 1014800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateAdd(LocalStackBase, ConstantInt::get(IntptrTy, Pos)), 1015800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AI->getType())); 1016800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Pos += AlignedSize + RedzoneSize; 1017800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1018800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(Pos == LocalStackSize); 1019800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1020800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Write the Magic value and the frame description constant to the redzone. 1021800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *BasePlus0 = IRB.CreateIntToPtr(LocalStackBase, IntptrPtrTy); 1022800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(ConstantInt::get(IntptrTy, kCurrentStackFrameMagic), 1023800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BasePlus0); 1024800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *BasePlus1 = IRB.CreateAdd(LocalStackBase, 1025800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, LongSize/8)); 1026800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BasePlus1 = IRB.CreateIntToPtr(BasePlus1, IntptrPtrTy); 1027800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Description = IRB.CreatePointerCast( 1028800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany createPrivateGlobalForString(M, StackDescription.str()), 1029800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IntptrTy); 1030800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(Description, BasePlus1); 1031800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1032800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Poison the stack redzones at the entry. 1033800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *ShadowBase = memToShadow(LocalStackBase, IRB); 1034800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany PoisonStack(ArrayRef<AllocaInst*>(AllocaVec), IRB, ShadowBase, true); 1035800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1036800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *AsanStackFreeFunc = NULL; 1037800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (DoStackMalloc) { 1038800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AsanStackFreeFunc = M.getOrInsertFunction( 1039800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany kAsanStackFreeName, IRB.getVoidTy(), 1040800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IntptrTy, IntptrTy, IntptrTy, NULL); 1041800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1042800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1043800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Unpoison the stack before all ret instructions. 1044800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0, n = RetVec.size(); i < n; i++) { 1045800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *Ret = RetVec[i]; 1046800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRBRet(Ret); 1047800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1048800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Mark the current frame as retired. 1049800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBRet.CreateStore(ConstantInt::get(IntptrTy, kRetiredStackFrameMagic), 1050800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BasePlus0); 1051800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Unpoison the stack. 1052800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany PoisonStack(ArrayRef<AllocaInst*>(AllocaVec), IRBRet, ShadowBase, false); 1053800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1054800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (DoStackMalloc) { 1055800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBRet.CreateCall3(AsanStackFreeFunc, LocalStackBase, 1056800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, LocalStackSize), 1057800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany OrigStackBase); 1058800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1059800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1060800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1061800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClDebugStack) { 1062800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany DEBUG(dbgs() << F); 1063800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1064800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1065800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return true; 1066800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 1067