AddressSanitizer.cpp revision 4172a8abbabea2359d91bb07101166565127d798
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 18d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include "llvm/Transforms/Instrumentation.h" 19800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/ArrayRef.h" 201c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov#include "llvm/ADT/DenseMap.h" 2159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov#include "llvm/ADT/DepthFirstIterator.h" 22800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/OwningPtr.h" 23800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/SmallSet.h" 24800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/SmallString.h" 25800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/SmallVector.h" 26800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/ADT/StringExtras.h" 2706fdbaa9145f01a291d4981ca5120b7bdcad44c6Evgeniy Stepanov#include "llvm/ADT/Triple.h" 281afbb517965e29b07cb42e2335d5eadd87de6535Alexey Samsonov#include "llvm/DIBuilder.h" 290b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/DataLayout.h" 300b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/Function.h" 310b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/IRBuilder.h" 320b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/InlineAsm.h" 330b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/IntrinsicInst.h" 340b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/LLVMContext.h" 350b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/Module.h" 360b8c9a80f20772c3793201ab5b251d3520b9cea3Chandler Carruth#include "llvm/IR/Type.h" 3759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov#include "llvm/InstVisitor.h" 381479c9bb392325688b72e5829bbb7939c4a079a4Kostya Serebryany#include "llvm/Support/CallSite.h" 39800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/CommandLine.h" 40800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/DataTypes.h" 41800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/Debug.h" 423e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany#include "llvm/Support/Endian.h" 43800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/raw_ostream.h" 44800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Support/system_error.h" 45800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Transforms/Utils/BasicBlockUtils.h" 4620985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany#include "llvm/Transforms/Utils/Cloning.h" 471afbb517965e29b07cb42e2335d5eadd87de6535Alexey Samsonov#include "llvm/Transforms/Utils/Local.h" 48800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include "llvm/Transforms/Utils/ModuleUtils.h" 49405515d55f470d04ef75f653b7f1994329c9066bPeter Collingbourne#include "llvm/Transforms/Utils/SpecialCaseList.h" 50800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany#include <algorithm> 51d04a8d4b33ff316ca4cf961e06c9e312eff8e64fChandler Carruth#include <string> 52800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 53800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanyusing namespace llvm; 54800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 55800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uint64_t kDefaultShadowScale = 3; 56800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uint64_t kDefaultShadowOffset32 = 1ULL << 29; 57800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uint64_t kDefaultShadowOffset64 = 1ULL << 44; 58117de489a0d5f4ff280fb173fe45bd5ce8514d93Kostya Serebryanystatic const uint64_t kDefaultShort64bitShadowOffset = 0x7FFF8000; // < 2G. 5948a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryanystatic const uint64_t kPPC64_ShadowOffset64 = 1ULL << 41; 603e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryanystatic const uint64_t kMIPS32_ShadowOffset32 = 0x0aaa8000; 61800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 62800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const size_t kMaxStackMallocSize = 1 << 16; // 64K 63800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uintptr_t kCurrentStackFrameMagic = 0x41B58AB3; 64800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const uintptr_t kRetiredStackFrameMagic = 0x45E0360E; 65800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 664172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanModuleCtorName = "asan.module_ctor"; 674172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanModuleDtorName = "asan.module_dtor"; 684172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const int kAsanCtorAndCtorPriority = 1; 694172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanReportErrorTemplate = "__asan_report_"; 704172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanReportLoadN = "__asan_report_load_n"; 714172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanReportStoreN = "__asan_report_store_n"; 724172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanRegisterGlobalsName = "__asan_register_globals"; 734172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanUnregisterGlobalsName = "__asan_unregister_globals"; 744172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanPoisonGlobalsName = "__asan_before_dynamic_init"; 754172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanUnpoisonGlobalsName = "__asan_after_dynamic_init"; 764172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanInitName = "__asan_init_v3"; 774172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanHandleNoReturnName = "__asan_handle_no_return"; 784172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanMappingOffsetName = "__asan_mapping_offset"; 794172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanMappingScaleName = "__asan_mapping_scale"; 804172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanStackMallocName = "__asan_stack_malloc"; 814172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanStackFreeName = "__asan_stack_free"; 824172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanGenPrefix = "__asan_gen_"; 834172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanPoisonStackMemoryName = 844172a8abbabea2359d91bb07101166565127d798Craig Topper "__asan_poison_stack_memory"; 854172a8abbabea2359d91bb07101166565127d798Craig Topperstatic const char *const kAsanUnpoisonStackMemoryName = 86f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov "__asan_unpoison_stack_memory"; 87800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 88800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const int kAsanStackLeftRedzoneMagic = 0xf1; 89800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const int kAsanStackMidRedzoneMagic = 0xf2; 90800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const int kAsanStackRightRedzoneMagic = 0xf3; 91800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic const int kAsanStackPartialRedzoneMagic = 0xf4; 92800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 93c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany// Accesses sizes are powers of two: 1, 2, 4, 8, 16. 94c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanystatic const size_t kNumberOfAccessSizes = 5; 95c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 96800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Command-line flags. 97800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 98800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -f[no-]asan-reads. 99800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClInstrumentReads("asan-instrument-reads", 100800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("instrument read instructions"), cl::Hidden, cl::init(true)); 101800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClInstrumentWrites("asan-instrument-writes", 102800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("instrument write instructions"), cl::Hidden, cl::init(true)); 103e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryanystatic cl::opt<bool> ClInstrumentAtomics("asan-instrument-atomics", 104e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany cl::desc("instrument atomic instructions (rmw, cmpxchg)"), 105e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany cl::Hidden, cl::init(true)); 1066e2d506dc962873a0e05092bbb034f9a615d1084Kostya Serebryanystatic cl::opt<bool> ClAlwaysSlowPath("asan-always-slow-path", 1076e2d506dc962873a0e05092bbb034f9a615d1084Kostya Serebryany cl::desc("use instrumentation with slow path for all accesses"), 1086e2d506dc962873a0e05092bbb034f9a615d1084Kostya Serebryany cl::Hidden, cl::init(false)); 109c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany// This flag limits the number of instructions to be instrumented 110324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany// in any given BB. Normally, this should be set to unlimited (INT_MAX), 111324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany// but due to http://llvm.org/bugs/show_bug.cgi?id=12652 we temporary 112324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany// set it to 10000. 113324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryanystatic cl::opt<int> ClMaxInsnsToInstrumentPerBB("asan-max-ins-per-bb", 114324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany cl::init(10000), 115324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany cl::desc("maximal number of instructions to instrument in any given BB"), 116324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany cl::Hidden); 117800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -f[no]asan-stack. 118800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClStack("asan-stack", 119800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Handle stack memory"), cl::Hidden, cl::init(true)); 120800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -f[no]asan-use-after-return. 121800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClUseAfterReturn("asan-use-after-return", 122800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Check return-after-free"), cl::Hidden, cl::init(false)); 123800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This flag may need to be replaced with -f[no]asan-globals. 124800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClGlobals("asan-globals", 125800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Handle global objects"), cl::Hidden, cl::init(true)); 1269b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryanystatic cl::opt<bool> ClInitializers("asan-initialization-order", 1279b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany cl::desc("Handle C++ initializer order"), cl::Hidden, cl::init(false)); 128800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClMemIntrin("asan-memintrin", 129800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Handle memset/memcpy/memmove"), cl::Hidden, cl::init(true)); 1306c55412ea4b39103a3a5764d49ddfdf50e066d56Kostya Serebryanystatic cl::opt<bool> ClRealignStack("asan-realign-stack", 1316c55412ea4b39103a3a5764d49ddfdf50e066d56Kostya Serebryany cl::desc("Realign stack to 32"), cl::Hidden, cl::init(true)); 132b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonovstatic cl::opt<std::string> ClBlacklistFile("asan-blacklist", 133b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonov cl::desc("File containing the list of objects to ignore " 134800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany "during instrumentation"), cl::Hidden); 135800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 13620985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// This is an experimental feature that will allow to choose between 13720985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// instrumented and non-instrumented code at link-time. 13820985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// If this option is on, just before instrumenting a function we create its 13920985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// clone; if the function is not changed by asan the clone is deleted. 14020985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// If we end up with a clone, we put the instrumented function into a section 14120985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// called "ASAN" and the uninstrumented function into a section called "NOASAN". 14220985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// 14320985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// This is still a prototype, we need to figure out a way to keep two copies of 14420985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany// a function so that the linker can easily choose one of them. 14520985711c76b8799d689a9c0e416b68896333c23Kostya Serebryanystatic cl::opt<bool> ClKeepUninstrumented("asan-keep-uninstrumented-functions", 14620985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany cl::desc("Keep uninstrumented copies of functions"), 14720985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany cl::Hidden, cl::init(false)); 14820985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany 149800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// These flags allow to change the shadow mapping. 150800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// The shadow mapping looks like 151800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Shadow = (Mem >> scale) + (1 << offset_log) 152800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClMappingScale("asan-mapping-scale", 153800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("scale of asan shadow mapping"), cl::Hidden, cl::init(0)); 154800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClMappingOffsetLog("asan-mapping-offset-log", 155800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("offset of asan shadow mapping"), cl::Hidden, cl::init(-1)); 156117de489a0d5f4ff280fb173fe45bd5ce8514d93Kostya Serebryanystatic cl::opt<bool> ClShort64BitOffset("asan-short-64bit-mapping-offset", 157117de489a0d5f4ff280fb173fe45bd5ce8514d93Kostya Serebryany cl::desc("Use short immediate constant as the mapping offset for 64bit"), 1580bc55d517e8e64f0f441736fba2447781c405ef4Kostya Serebryany cl::Hidden, cl::init(true)); 159800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 160800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Optimization flags. Not user visible, used mostly for testing 161800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// and benchmarking the tool. 162800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClOpt("asan-opt", 163800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Optimize instrumentation"), cl::Hidden, cl::init(true)); 164800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClOptSameTemp("asan-opt-same-temp", 165800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Instrument the same temp just once"), cl::Hidden, 166800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::init(true)); 167800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<bool> ClOptGlobals("asan-opt-globals", 168800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::desc("Don't instrument scalar globals"), cl::Hidden, cl::init(true)); 169800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 170ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonovstatic cl::opt<bool> ClCheckLifetime("asan-check-lifetime", 171ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov cl::desc("Use llvm.lifetime intrinsics to insert extra checks"), 172ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov cl::Hidden, cl::init(false)); 173ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov 174800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Debug flags. 175800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClDebug("asan-debug", cl::desc("debug"), cl::Hidden, 176800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::init(0)); 177800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClDebugStack("asan-debug-stack", cl::desc("debug stack"), 178800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::Hidden, cl::init(0)); 179800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<std::string> ClDebugFunc("asan-debug-func", 180800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::Hidden, cl::desc("Debug func")); 181800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClDebugMin("asan-debug-min", cl::desc("Debug min inst"), 182800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::Hidden, cl::init(-1)); 183800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic cl::opt<int> ClDebugMax("asan-debug-max", cl::desc("Debug man inst"), 184800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany cl::Hidden, cl::init(-1)); 185800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 186800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanynamespace { 187ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany/// A set of dynamically initialized globals extracted from metadata. 188ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryanyclass SetOfDynamicallyInitializedGlobals { 189ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany public: 190ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany void Init(Module& M) { 191ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany // Clang generates metadata identifying all dynamically initialized globals. 192ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany NamedMDNode *DynamicGlobals = 193ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany M.getNamedMetadata("llvm.asan.dynamically_initialized_globals"); 194ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany if (!DynamicGlobals) 195ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany return; 196ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany for (int i = 0, n = DynamicGlobals->getNumOperands(); i < n; ++i) { 197ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany MDNode *MDN = DynamicGlobals->getOperand(i); 198ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany assert(MDN->getNumOperands() == 1); 199ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany Value *VG = MDN->getOperand(0); 200ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany // The optimizer may optimize away a global entirely, in which case we 201ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany // cannot instrument access to it. 202ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany if (!VG) 203ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany continue; 204ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany DynInitGlobals.insert(cast<GlobalVariable>(VG)); 205ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany } 206ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany } 207ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany bool Contains(GlobalVariable *G) { return DynInitGlobals.count(G) != 0; } 208ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany private: 209ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany SmallSet<GlobalValue*, 32> DynInitGlobals; 210ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany}; 211ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany 21219cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov/// This struct defines the shadow mapping using the rule: 21348a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany/// shadow = (mem >> Scale) ADD-or-OR Offset. 21419cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonovstruct ShadowMapping { 21519cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov int Scale; 21619cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov uint64_t Offset; 21748a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany bool OrShadowOffset; 21819cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov}; 21919cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov 22011af9a873f9e1409a422ab31e22729368805afafAlexey Samsonovstatic ShadowMapping getShadowMapping(const Module &M, int LongSize, 22111af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov bool ZeroBaseShadow) { 22211af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov llvm::Triple TargetTriple(M.getTargetTriple()); 22311af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov bool IsAndroid = TargetTriple.getEnvironment() == llvm::Triple::Android; 224c8a196ae8fad3cba7a777e2e7916fd36ebf70fe6Alexander Potapenko bool IsMacOSX = TargetTriple.getOS() == llvm::Triple::MacOSX; 22548a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany bool IsPPC64 = TargetTriple.getArch() == llvm::Triple::ppc64; 2260bc55d517e8e64f0f441736fba2447781c405ef4Kostya Serebryany bool IsX86_64 = TargetTriple.getArch() == llvm::Triple::x86_64; 2273e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany bool IsMIPS32 = TargetTriple.getArch() == llvm::Triple::mips || 2283e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany TargetTriple.getArch() == llvm::Triple::mipsel; 22919cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov 23019cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov ShadowMapping Mapping; 23119cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov 23248a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany // OR-ing shadow offset if more efficient (at least on x86), 23348a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany // but on ppc64 we have to use add since the shadow offset is not neccesary 23448a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany // 1/8-th of the address space. 235117de489a0d5f4ff280fb173fe45bd5ce8514d93Kostya Serebryany Mapping.OrShadowOffset = !IsPPC64 && !ClShort64BitOffset; 23648a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany 23711af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov Mapping.Offset = (IsAndroid || ZeroBaseShadow) ? 0 : 2383e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany (LongSize == 32 ? 2393e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany (IsMIPS32 ? kMIPS32_ShadowOffset32 : kDefaultShadowOffset32) : 24048a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany IsPPC64 ? kPPC64_ShadowOffset64 : kDefaultShadowOffset64); 241c8a196ae8fad3cba7a777e2e7916fd36ebf70fe6Alexander Potapenko if (!ZeroBaseShadow && ClShort64BitOffset && IsX86_64 && !IsMacOSX) { 2420bc55d517e8e64f0f441736fba2447781c405ef4Kostya Serebryany assert(LongSize == 64); 243117de489a0d5f4ff280fb173fe45bd5ce8514d93Kostya Serebryany Mapping.Offset = kDefaultShort64bitShadowOffset; 24439f02940ba085af79011f7e9095bf9902cd0fa6fKostya Serebryany } 24539f02940ba085af79011f7e9095bf9902cd0fa6fKostya Serebryany if (!ZeroBaseShadow && ClMappingOffsetLog >= 0) { 24619cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov // Zero offset log is the special case. 24719cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov Mapping.Offset = (ClMappingOffsetLog == 0) ? 0 : 1ULL << ClMappingOffsetLog; 24819cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov } 24919cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov 25019cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov Mapping.Scale = kDefaultShadowScale; 25119cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov if (ClMappingScale) { 25219cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov Mapping.Scale = ClMappingScale; 25319cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov } 25419cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov 25519cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov return Mapping; 256b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany} 257b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany 25819cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonovstatic size_t RedzoneSizeForScale(int MappingScale) { 259b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany // Redzone used for stack and globals is at least 32 bytes. 260b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany // For scales 6 and 7, the redzone has to be 64 and 128 bytes respectively. 26119cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov return std::max(32U, 1U << MappingScale); 262b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany} 263ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany 264800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany/// AddressSanitizer: instrument the code in module to find memory bugs. 265ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryanystruct AddressSanitizer : public FunctionPass { 266b4ba5e68e1ac00bfb93572a1f271673deefd7ea9Alexey Samsonov AddressSanitizer(bool CheckInitOrder = true, 267ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov bool CheckUseAfterReturn = false, 268b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonov bool CheckLifetime = false, 26911af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov StringRef BlacklistFile = StringRef(), 27011af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov bool ZeroBaseShadow = false) 271ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov : FunctionPass(ID), 272ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov CheckInitOrder(CheckInitOrder || ClInitializers), 273ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov CheckUseAfterReturn(CheckUseAfterReturn || ClUseAfterReturn), 274b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonov CheckLifetime(CheckLifetime || ClCheckLifetime), 275b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonov BlacklistFile(BlacklistFile.empty() ? ClBlacklistFile 27611af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov : BlacklistFile), 27711af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov ZeroBaseShadow(ZeroBaseShadow) {} 2781416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany virtual const char *getPassName() const { 2791416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany return "AddressSanitizerFunctionPass"; 2801416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany } 281ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany void instrumentMop(Instruction *I); 2826ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany void instrumentAddress(Instruction *OrigIns, Instruction *InsertBefore, 2836ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *Addr, uint32_t TypeSize, bool IsWrite, 2846ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *SizeArgument); 285c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *createSlowPathCmp(IRBuilder<> &IRB, Value *AddrLong, 286c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *ShadowValue, uint32_t TypeSize); 287ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany Instruction *generateCrashCode(Instruction *InsertBefore, Value *Addr, 2886ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany bool IsWrite, size_t AccessSizeIndex, 2896ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *SizeArgument); 290ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany bool instrumentMemIntrinsic(MemIntrinsic *MI); 291ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany void instrumentMemIntrinsicParam(Instruction *OrigIns, Value *Addr, 292c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *Size, 293800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *InsertBefore, bool IsWrite); 294800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *memToShadow(Value *Shadow, IRBuilder<> &IRB); 295ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany bool runOnFunction(Function &F); 296a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany bool maybeInsertAsanInitAtFunctionEntry(Function &F); 29719cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov void emitShadowMapping(Module &M, IRBuilder<> &IRB) const; 298ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany virtual bool doInitialization(Module &M); 299800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany static char ID; // Pass identification, replacement for typeid 300800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 301800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany private: 3028b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany void initializeCallbacks(Module &M); 303800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 3049b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany bool ShouldInstrumentGlobal(GlobalVariable *G); 3055a3a9c937198084498a196dae856ac5a5a005bccKostya Serebryany bool LooksLikeCodeInBug11395(Instruction *I); 3069b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany void FindDynamicInitializers(Module &M); 307800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 308ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov bool CheckInitOrder; 309ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov bool CheckUseAfterReturn; 310ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov bool CheckLifetime; 31111af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov SmallString<64> BlacklistFile; 31211af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov bool ZeroBaseShadow; 31311af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov 314800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany LLVMContext *C; 3153574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow DataLayout *TD; 316800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany int LongSize; 317800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *IntptrTy; 31819cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov ShadowMapping Mapping; 319800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Function *AsanCtorFunction; 320800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Function *AsanInitFunction; 321ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany Function *AsanHandleNoReturnFunc; 322405515d55f470d04ef75f653b7f1994329c9066bPeter Collingbourne OwningPtr<SpecialCaseList> BL; 3239db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany // This array is indexed by AccessIsWrite and log2(AccessSize). 3249db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany Function *AsanErrorCallback[2][kNumberOfAccessSizes]; 3256ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany // This array is indexed by AccessIsWrite. 3266ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Function *AsanErrorCallbackSized[2]; 327f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany InlineAsm *EmptyAsm; 328ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany SetOfDynamicallyInitializedGlobals DynamicallyInitializedGlobals; 32959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 33059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov friend struct FunctionStackPoisoner; 331800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany}; 332c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 3331416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryanyclass AddressSanitizerModule : public ModulePass { 334b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany public: 335b4ba5e68e1ac00bfb93572a1f271673deefd7ea9Alexey Samsonov AddressSanitizerModule(bool CheckInitOrder = true, 33611af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov StringRef BlacklistFile = StringRef(), 33711af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov bool ZeroBaseShadow = false) 338ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov : ModulePass(ID), 339b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonov CheckInitOrder(CheckInitOrder || ClInitializers), 340b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonov BlacklistFile(BlacklistFile.empty() ? ClBlacklistFile 34111af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov : BlacklistFile), 34211af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov ZeroBaseShadow(ZeroBaseShadow) {} 3431416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany bool runOnModule(Module &M); 3441416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany static char ID; // Pass identification, replacement for typeid 3451416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany virtual const char *getPassName() const { 3461416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany return "AddressSanitizerModule"; 3471416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany } 348f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov 349b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany private: 3504684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov void initializeCallbacks(Module &M); 3514684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov 352b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany bool ShouldInstrumentGlobal(GlobalVariable *G); 353ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov void createInitializerPoisonCalls(Module &M, GlobalValue *ModuleName); 35419cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov size_t RedzoneSize() const { 35519cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov return RedzoneSizeForScale(Mapping.Scale); 35619cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov } 357b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany 358ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov bool CheckInitOrder; 359b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonov SmallString<64> BlacklistFile; 36011af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov bool ZeroBaseShadow; 36111af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov 362405515d55f470d04ef75f653b7f1994329c9066bPeter Collingbourne OwningPtr<SpecialCaseList> BL; 363b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany SetOfDynamicallyInitializedGlobals DynamicallyInitializedGlobals; 364b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany Type *IntptrTy; 365b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany LLVMContext *C; 3661416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany DataLayout *TD; 36719cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov ShadowMapping Mapping; 3684684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov Function *AsanPoisonGlobals; 3694684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov Function *AsanUnpoisonGlobals; 3704684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov Function *AsanRegisterGlobals; 3714684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov Function *AsanUnregisterGlobals; 372b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany}; 373b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany 37459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// Stack poisoning does not play well with exception handling. 37559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// When an exception is thrown, we essentially bypass the code 37659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// that unpoisones the stack. This is why the run-time library has 37759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// to intercept __cxa_throw (as well as longjmp, etc) and unpoison the entire 37859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// stack in the interceptor. This however does not work inside the 37959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// actual function which catches the exception. Most likely because the 38059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// compiler hoists the load of the shadow value somewhere too high. 38159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// This causes asan to report a non-existing bug on 453.povray. 38259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// It sounds like an LLVM bug. 38359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonovstruct FunctionStackPoisoner : public InstVisitor<FunctionStackPoisoner> { 38459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Function &F; 38559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov AddressSanitizer &ASan; 38659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov DIBuilder DIB; 38759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov LLVMContext *C; 38859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Type *IntptrTy; 38959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Type *IntptrPtrTy; 39019cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov ShadowMapping Mapping; 39159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 39259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov SmallVector<AllocaInst*, 16> AllocaVec; 39359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov SmallVector<Instruction*, 8> RetVec; 39459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov uint64_t TotalStackSize; 39559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov unsigned StackAlignment; 39659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 39759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Function *AsanStackMallocFunc, *AsanStackFreeFunc; 39859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Function *AsanPoisonStackMemoryFunc, *AsanUnpoisonStackMemoryFunc; 39959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 4001c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Stores a place and arguments of poisoning/unpoisoning call for alloca. 4011c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov struct AllocaPoisonCall { 4021c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov IntrinsicInst *InsBefore; 4031c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov uint64_t Size; 4041c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov bool DoPoison; 4051c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov }; 4061c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov SmallVector<AllocaPoisonCall, 8> AllocaPoisonCallVec; 4071c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov 4081c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Maps Value to an AllocaInst from which the Value is originated. 4091c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov typedef DenseMap<Value*, AllocaInst*> AllocaForValueMapTy; 4101c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaForValueMapTy AllocaForValue; 4111c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov 41259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov FunctionStackPoisoner(Function &F, AddressSanitizer &ASan) 41359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov : F(F), ASan(ASan), DIB(*F.getParent()), C(ASan.C), 41459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov IntptrTy(ASan.IntptrTy), IntptrPtrTy(PointerType::get(IntptrTy, 0)), 41519cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov Mapping(ASan.Mapping), 41619cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov TotalStackSize(0), StackAlignment(1 << Mapping.Scale) {} 41759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 41859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov bool runOnFunction() { 41959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov if (!ClStack) return false; 42059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov // Collect alloca, ret, lifetime instructions etc. 42159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov for (df_iterator<BasicBlock*> DI = df_begin(&F.getEntryBlock()), 42259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov DE = df_end(&F.getEntryBlock()); DI != DE; ++DI) { 42359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov BasicBlock *BB = *DI; 42459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov visit(*BB); 42559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 42659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov if (AllocaVec.empty()) return false; 42759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 42859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov initializeCallbacks(*F.getParent()); 42959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 43059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov poisonStack(); 43159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 43259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov if (ClDebugStack) { 43359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov DEBUG(dbgs() << F); 43459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 43559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov return true; 43659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 43759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 43859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov // Finds all static Alloca instructions and puts 43959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov // poisoned red zones around all of them. 44059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov // Then unpoison everything back before the function returns. 44159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov void poisonStack(); 44259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 44359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov // ----------------------- Visitors. 44459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov /// \brief Collect all Ret instructions. 44559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov void visitReturnInst(ReturnInst &RI) { 44659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov RetVec.push_back(&RI); 44759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 44859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 44959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov /// \brief Collect Alloca instructions we want (and can) handle. 45059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov void visitAllocaInst(AllocaInst &AI) { 4511c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (!isInterestingAlloca(AI)) return; 45259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 45359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov StackAlignment = std::max(StackAlignment, AI.getAlignment()); 45459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov AllocaVec.push_back(&AI); 455d4429214a2dffcfd8f97956ac8b1a67c4795d242Kostya Serebryany uint64_t AlignedSize = getAlignedAllocaSize(&AI); 45659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov TotalStackSize += AlignedSize; 45759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 45859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 4591c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov /// \brief Collect lifetime intrinsic calls to check for use-after-scope 4601c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov /// errors. 4611c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov void visitIntrinsicInst(IntrinsicInst &II) { 4621c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (!ASan.CheckLifetime) return; 4631c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov Intrinsic::ID ID = II.getIntrinsicID(); 4641c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (ID != Intrinsic::lifetime_start && 4651c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov ID != Intrinsic::lifetime_end) 4661c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov return; 4671c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Found lifetime intrinsic, add ASan instrumentation if necessary. 4681c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov ConstantInt *Size = dyn_cast<ConstantInt>(II.getArgOperand(0)); 4691c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // If size argument is undefined, don't do anything. 4701c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (Size->isMinusOne()) return; 4711c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Check that size doesn't saturate uint64_t and can 4721c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // be stored in IntptrTy. 4731c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov const uint64_t SizeValue = Size->getValue().getLimitedValue(); 4741c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (SizeValue == ~0ULL || 4751c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov !ConstantInt::isValueValidForType(IntptrTy, SizeValue)) 4761c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov return; 4771c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Find alloca instruction that corresponds to llvm.lifetime argument. 4781c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaInst *AI = findAllocaForValue(II.getArgOperand(1)); 4791c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (!AI) return; 4801c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov bool DoPoison = (ID == Intrinsic::lifetime_end); 4811c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaPoisonCall APC = {&II, SizeValue, DoPoison}; 4821c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaPoisonCallVec.push_back(APC); 4831c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov } 4841c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov 48559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov // ---------------------- Helpers. 48659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov void initializeCallbacks(Module &M); 48759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 4881c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Check if we want (and can) handle this alloca. 4891c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov bool isInterestingAlloca(AllocaInst &AI) { 4901c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov return (!AI.isArrayAllocation() && 4911c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AI.isStaticAlloca() && 492d4429214a2dffcfd8f97956ac8b1a67c4795d242Kostya Serebryany AI.getAlignment() <= RedzoneSize() && 4931c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AI.getAllocatedType()->isSized()); 4941c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov } 4951c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov 49619cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov size_t RedzoneSize() const { 49719cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov return RedzoneSizeForScale(Mapping.Scale); 49819cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov } 49959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov uint64_t getAllocaSizeInBytes(AllocaInst *AI) { 50059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Type *Ty = AI->getAllocatedType(); 50159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov uint64_t SizeInBytes = ASan.TD->getTypeAllocSize(Ty); 50259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov return SizeInBytes; 50359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 50459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov uint64_t getAlignedSize(uint64_t SizeInBytes) { 50559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov size_t RZ = RedzoneSize(); 50659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov return ((SizeInBytes + RZ - 1) / RZ) * RZ; 50759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 50859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov uint64_t getAlignedAllocaSize(AllocaInst *AI) { 50959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov uint64_t SizeInBytes = getAllocaSizeInBytes(AI); 51059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov return getAlignedSize(SizeInBytes); 51159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 5121c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov /// Finds alloca where the value comes from. 5131c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaInst *findAllocaForValue(Value *V); 51459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov void poisonRedZones(const ArrayRef<AllocaInst*> &AllocaVec, IRBuilder<> IRB, 51559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Value *ShadowBase, bool DoPoison); 51659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov void poisonAlloca(Value *V, uint64_t Size, IRBuilder<> IRB, bool DoPoison); 51759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov}; 51859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 519800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} // namespace 520800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 521800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanychar AddressSanitizer::ID = 0; 522800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya SerebryanyINITIALIZE_PASS(AddressSanitizer, "asan", 523800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany "AddressSanitizer: detects use-after-free and out-of-bounds bugs.", 524800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany false, false) 525ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey SamsonovFunctionPass *llvm::createAddressSanitizerFunctionPass( 526b0dcf61252e58715a3bea79f4c112572df361c30Alexey Samsonov bool CheckInitOrder, bool CheckUseAfterReturn, bool CheckLifetime, 52711af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov StringRef BlacklistFile, bool ZeroBaseShadow) { 528ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov return new AddressSanitizer(CheckInitOrder, CheckUseAfterReturn, 52911af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov CheckLifetime, BlacklistFile, ZeroBaseShadow); 530800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 531800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 5321416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryanychar AddressSanitizerModule::ID = 0; 5331416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya SerebryanyINITIALIZE_PASS(AddressSanitizerModule, "asan-module", 5341416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany "AddressSanitizer: detects use-after-free and out-of-bounds bugs." 5351416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany "ModulePass", false, false) 536b0dcf61252e58715a3bea79f4c112572df361c30Alexey SamsonovModulePass *llvm::createAddressSanitizerModulePass( 53711af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov bool CheckInitOrder, StringRef BlacklistFile, bool ZeroBaseShadow) { 53811af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov return new AddressSanitizerModule(CheckInitOrder, BlacklistFile, 53911af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov ZeroBaseShadow); 54025878042030e85c244b41bfcdfad27c32360e2ecAlexander Potapenko} 54125878042030e85c244b41bfcdfad27c32360e2ecAlexander Potapenko 5422735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryanystatic size_t TypeSizeToSizeIndex(uint32_t TypeSize) { 543c6af2432c802d241c8fffbe0371c023e6c58844eMichael J. Spencer size_t Res = countTrailingZeros(TypeSize / 8); 5442735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany assert(Res < kNumberOfAccessSizes); 5452735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany return Res; 5462735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany} 5472735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany 548800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Create a constant for Str so that we can pass it to the run-time lib. 549800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic GlobalVariable *createPrivateGlobalForString(Module &M, StringRef Str) { 55018c7f80b3e83ab584bd8572695a3cde8bafd9d3cChris Lattner Constant *StrConst = ConstantDataArray::getString(M.getContext(), Str); 5515111627ac1b0ae8a5a9d4dc1be8b22939ba850d0Kostya Serebryany GlobalVariable *GV = new GlobalVariable(M, StrConst->getType(), true, 55251c7c65e32f76ec5a50cdecfe2b4c287c57da127Kostya Serebryany GlobalValue::PrivateLinkage, StrConst, 55351c7c65e32f76ec5a50cdecfe2b4c287c57da127Kostya Serebryany kAsanGenPrefix); 5545111627ac1b0ae8a5a9d4dc1be8b22939ba850d0Kostya Serebryany GV->setUnnamedAddr(true); // Ok to merge these. 5555111627ac1b0ae8a5a9d4dc1be8b22939ba850d0Kostya Serebryany GV->setAlignment(1); // Strings may not be merged w/o setting align 1. 5565111627ac1b0ae8a5a9d4dc1be8b22939ba850d0Kostya Serebryany return GV; 55751c7c65e32f76ec5a50cdecfe2b4c287c57da127Kostya Serebryany} 55851c7c65e32f76ec5a50cdecfe2b4c287c57da127Kostya Serebryany 55951c7c65e32f76ec5a50cdecfe2b4c287c57da127Kostya Serebryanystatic bool GlobalWasGeneratedByAsan(GlobalVariable *G) { 56051c7c65e32f76ec5a50cdecfe2b4c287c57da127Kostya Serebryany return G->getName().find(kAsanGenPrefix) == 0; 561800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 562800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 563800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya SerebryanyValue *AddressSanitizer::memToShadow(Value *Shadow, IRBuilder<> &IRB) { 564800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Shadow >> scale 56519cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov Shadow = IRB.CreateLShr(Shadow, Mapping.Scale); 56619cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov if (Mapping.Offset == 0) 567800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return Shadow; 568800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // (Shadow >> scale) | offset 56948a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany if (Mapping.OrShadowOffset) 57048a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany return IRB.CreateOr(Shadow, ConstantInt::get(IntptrTy, Mapping.Offset)); 57148a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany else 57248a615fee78c3c262c60147a65dc6fff5fd6bb3bKostya Serebryany return IRB.CreateAdd(Shadow, ConstantInt::get(IntptrTy, Mapping.Offset)); 573800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 574800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 575c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryanyvoid AddressSanitizer::instrumentMemIntrinsicParam( 576ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany Instruction *OrigIns, 577800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Addr, Value *Size, Instruction *InsertBefore, bool IsWrite) { 5786ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany IRBuilder<> IRB(InsertBefore); 5796ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany if (Size->getType() != IntptrTy) 5806ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Size = IRB.CreateIntCast(Size, IntptrTy, false); 581800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Check the first byte. 5826ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany instrumentAddress(OrigIns, InsertBefore, Addr, 8, IsWrite, Size); 583800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Check the last byte. 5846ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany IRB.SetInsertPoint(InsertBefore); 5856ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *SizeMinusOne = IRB.CreateSub(Size, ConstantInt::get(IntptrTy, 1)); 5866ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *AddrLong = IRB.CreatePointerCast(Addr, IntptrTy); 5876ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *AddrLast = IRB.CreateAdd(AddrLong, SizeMinusOne); 5886ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany instrumentAddress(OrigIns, InsertBefore, AddrLast, 8, IsWrite, Size); 589800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 590800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 591800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// Instrument memset/memmove/memcpy 592ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryanybool AddressSanitizer::instrumentMemIntrinsic(MemIntrinsic *MI) { 593800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Dst = MI->getDest(); 594800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany MemTransferInst *MemTran = dyn_cast<MemTransferInst>(MI); 5952735cf4aa52e31b8d2de90f836c3ad991215e04eKostya Serebryany Value *Src = MemTran ? MemTran->getSource() : 0; 596800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Length = MI->getLength(); 597800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 598800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Constant *ConstLength = dyn_cast<Constant>(Length); 599800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *InsertBefore = MI; 600800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ConstLength) { 601800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ConstLength->isNullValue()) return false; 602800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else { 603800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // The size is not a constant so it could be zero -- check at run-time. 604800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(InsertBefore); 605800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 606800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Cmp = IRB.CreateICmpNE(Length, 60756139bc493790612ee6281630678e293be6b2eb2Kostya Serebryany Constant::getNullValue(Length->getType())); 6084a2dec05cef5882b745dd248d79e42a42cdbc87bEvgeniy Stepanov InsertBefore = SplitBlockAndInsertIfThen(cast<Instruction>(Cmp), false); 609800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 610800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 611ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany instrumentMemIntrinsicParam(MI, Dst, Length, InsertBefore, true); 612800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (Src) 613ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany instrumentMemIntrinsicParam(MI, Src, Length, InsertBefore, false); 614800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return true; 615800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 616800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 617e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany// If I is an interesting memory access, return the PointerOperand 618e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany// and set IsWrite. Otherwise return NULL. 619e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryanystatic Value *isInterestingMemoryAccess(Instruction *I, bool *IsWrite) { 620800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (LoadInst *LI = dyn_cast<LoadInst>(I)) { 621e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (!ClInstrumentReads) return NULL; 622e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany *IsWrite = false; 623800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return LI->getPointerOperand(); 624800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 625e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (StoreInst *SI = dyn_cast<StoreInst>(I)) { 626e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (!ClInstrumentWrites) return NULL; 627e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany *IsWrite = true; 628e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany return SI->getPointerOperand(); 629e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany } 630e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (AtomicRMWInst *RMW = dyn_cast<AtomicRMWInst>(I)) { 631e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (!ClInstrumentAtomics) return NULL; 632e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany *IsWrite = true; 633e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany return RMW->getPointerOperand(); 634e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany } 635e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (AtomicCmpXchgInst *XCHG = dyn_cast<AtomicCmpXchgInst>(I)) { 636e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (!ClInstrumentAtomics) return NULL; 637e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany *IsWrite = true; 638e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany return XCHG->getPointerOperand(); 639e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany } 640e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany return NULL; 641800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 642800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 643ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryanyvoid AddressSanitizer::instrumentMop(Instruction *I) { 6443780ad8b998d93d7db406919c06137cdb786ef05Axel Naumann bool IsWrite = false; 645e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany Value *Addr = isInterestingMemoryAccess(I, &IsWrite); 646e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany assert(Addr); 6479b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (ClOpt && ClOptGlobals) { 6489b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (GlobalVariable *G = dyn_cast<GlobalVariable>(Addr)) { 6499b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // If initialization order checking is disabled, a simple access to a 6509b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // dynamically initialized global is always valid. 651ee548275c63a1eeffda9d3edd2bea04e1dadcc67Alexey Samsonov if (!CheckInitOrder) 6529b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return; 6539b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // If a global variable does not have dynamic initialization we don't 654407790604b8f71f7172bbdfb76c27e1799d241c2Kostya Serebryany // have to instrument it. However, if a global does not have initailizer 655407790604b8f71f7172bbdfb76c27e1799d241c2Kostya Serebryany // at all, we assume it has dynamic initializer (in other TU). 656407790604b8f71f7172bbdfb76c27e1799d241c2Kostya Serebryany if (G->hasInitializer() && !DynamicallyInitializedGlobals.Contains(G)) 6579b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return; 6589b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany } 659800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 6609b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 661800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *OrigPtrTy = Addr->getType(); 662800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *OrigTy = cast<PointerType>(OrigPtrTy)->getElementType(); 663800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 664800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(OrigTy->isSized()); 665605ff6655b31033dde21e61416751847bd0ee201Kostya Serebryany uint32_t TypeSize = TD->getTypeStoreSizeInBits(OrigTy); 666800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 6676ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany assert((TypeSize % 8) == 0); 668800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 6696ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany // Instrument a 1-, 2-, 4-, 8-, or 16- byte access with one check. 6706ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany if (TypeSize == 8 || TypeSize == 16 || 6716ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany TypeSize == 32 || TypeSize == 64 || TypeSize == 128) 6726ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany return instrumentAddress(I, I, Addr, TypeSize, IsWrite, 0); 6736ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany // Instrument unusual size (but still multiple of 8). 6746ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany // We can not do it with a single check, so we do 1-byte check for the first 6756ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany // and the last bytes. We call __asan_report_*_n(addr, real_size) to be able 6766ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany // to report the actual access size. 677800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(I); 6786ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *LastByte = IRB.CreateIntToPtr( 6796ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany IRB.CreateAdd(IRB.CreatePointerCast(Addr, IntptrTy), 6806ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany ConstantInt::get(IntptrTy, TypeSize / 8 - 1)), 6816ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany OrigPtrTy); 6826ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *Size = ConstantInt::get(IntptrTy, TypeSize / 8); 6836ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany instrumentAddress(I, I, Addr, 8, IsWrite, Size); 6846ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany instrumentAddress(I, I, LastByte, 8, IsWrite, Size); 685800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 686800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 68755cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko// Validate the result of Module::getOrInsertFunction called for an interface 68855cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko// function of AddressSanitizer. If the instrumented module defines a function 68955cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko// with the same name, their prototypes must match, otherwise 69055cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko// getOrInsertFunction returns a bitcast. 691b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryanystatic Function *checkInterfaceFunction(Constant *FuncOrBitcast) { 69255cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko if (isa<Function>(FuncOrBitcast)) return cast<Function>(FuncOrBitcast); 69355cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko FuncOrBitcast->dump(); 69455cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko report_fatal_error("trying to redefine an AddressSanitizer " 69555cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko "interface function"); 69655cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko} 69755cabae685991ac6bc6d96b14e2139f64a0c9967Alexander Potapenko 698800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya SerebryanyInstruction *AddressSanitizer::generateCrashCode( 699ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany Instruction *InsertBefore, Value *Addr, 7006ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany bool IsWrite, size_t AccessSizeIndex, Value *SizeArgument) { 701ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany IRBuilder<> IRB(InsertBefore); 7026ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany CallInst *Call = SizeArgument 7036ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany ? IRB.CreateCall2(AsanErrorCallbackSized[IsWrite], Addr, SizeArgument) 7046ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany : IRB.CreateCall(AsanErrorCallback[IsWrite][AccessSizeIndex], Addr); 7056ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany 706f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany // We don't do Call->setDoesNotReturn() because the BB already has 707f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany // UnreachableInst at the end. 708f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany // This EmptyAsm is required to avoid callback merge. 709f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany IRB.CreateCall(EmptyAsm); 7103c7faae346f548c55cad86d82a2e242443001f23Kostya Serebryany return Call; 711800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 712800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 7132735cf4aa52e31b8d2de90f836c3ad991215e04eKostya SerebryanyValue *AddressSanitizer::createSlowPathCmp(IRBuilder<> &IRB, Value *AddrLong, 714c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *ShadowValue, 715c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany uint32_t TypeSize) { 71619cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov size_t Granularity = 1 << Mapping.Scale; 717c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // Addr & (Granularity - 1) 718c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *LastAccessedByte = IRB.CreateAnd( 719c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany AddrLong, ConstantInt::get(IntptrTy, Granularity - 1)); 720c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // (Addr & (Granularity - 1)) + size - 1 721c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany if (TypeSize / 8 > 1) 722c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany LastAccessedByte = IRB.CreateAdd( 723c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany LastAccessedByte, ConstantInt::get(IntptrTy, TypeSize / 8 - 1)); 724c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // (uint8_t) ((Addr & (Granularity-1)) + size - 1) 725c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany LastAccessedByte = IRB.CreateIntCast( 7266e2d506dc962873a0e05092bbb034f9a615d1084Kostya Serebryany LastAccessedByte, ShadowValue->getType(), false); 727c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany // ((uint8_t) ((Addr & (Granularity-1)) + size - 1)) >= ShadowValue 728c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany return IRB.CreateICmpSGE(LastAccessedByte, ShadowValue); 729c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany} 730c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany 731ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryanyvoid AddressSanitizer::instrumentAddress(Instruction *OrigIns, 7326ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Instruction *InsertBefore, 7336ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Value *Addr, uint32_t TypeSize, 7346ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany bool IsWrite, Value *SizeArgument) { 7356ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany IRBuilder<> IRB(InsertBefore); 736800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *AddrLong = IRB.CreatePointerCast(Addr, IntptrTy); 737800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 738800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *ShadowTy = IntegerType::get( 73919cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov *C, std::max(8U, TypeSize >> Mapping.Scale)); 740800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *ShadowPtrTy = PointerType::get(ShadowTy, 0); 741800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *ShadowPtr = memToShadow(AddrLong, IRB); 742800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *CmpVal = Constant::getNullValue(ShadowTy); 743800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *ShadowValue = IRB.CreateLoad( 744800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateIntToPtr(ShadowPtr, ShadowPtrTy)); 745800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 746800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Cmp = IRB.CreateICmpNE(ShadowValue, CmpVal); 74711c2a47af825a0f89d75aaa97ad873ed2acef266Kostya Serebryany size_t AccessSizeIndex = TypeSizeToSizeIndex(TypeSize); 74819cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov size_t Granularity = 1 << Mapping.Scale; 749ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany TerminatorInst *CrashTerm = 0; 750ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany 7516e2d506dc962873a0e05092bbb034f9a615d1084Kostya Serebryany if (ClAlwaysSlowPath || (TypeSize < 8 * Granularity)) { 7524a2dec05cef5882b745dd248d79e42a42cdbc87bEvgeniy Stepanov TerminatorInst *CheckTerm = 7534a2dec05cef5882b745dd248d79e42a42cdbc87bEvgeniy Stepanov SplitBlockAndInsertIfThen(cast<Instruction>(Cmp), false); 754ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany assert(dyn_cast<BranchInst>(CheckTerm)->isUnconditional()); 755f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany BasicBlock *NextBB = CheckTerm->getSuccessor(0); 756c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany IRB.SetInsertPoint(CheckTerm); 757c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany Value *Cmp2 = createSlowPathCmp(IRB, AddrLong, ShadowValue, TypeSize); 758ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany BasicBlock *CrashBlock = 759ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany BasicBlock::Create(*C, "", NextBB->getParent(), NextBB); 760ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany CrashTerm = new UnreachableInst(*C, CrashBlock); 761f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany BranchInst *NewTerm = BranchInst::Create(CrashBlock, NextBB, Cmp2); 762f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany ReplaceInstWithInst(CheckTerm, NewTerm); 763c0ed3e548c6f688e22685de04e210c7b59ac3433Kostya Serebryany } else { 7644a2dec05cef5882b745dd248d79e42a42cdbc87bEvgeniy Stepanov CrashTerm = SplitBlockAndInsertIfThen(cast<Instruction>(Cmp), true); 765800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 766ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany 7676ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany Instruction *Crash = generateCrashCode( 7686ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany CrashTerm, AddrLong, IsWrite, AccessSizeIndex, SizeArgument); 769ebd6454929f2ba3b92f61c151eccde0b8b0a8dedKostya Serebryany Crash->setDebugLoc(OrigIns->getDebugLoc()); 770800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 771800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 7721416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryanyvoid AddressSanitizerModule::createInitializerPoisonCalls( 773ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov Module &M, GlobalValue *ModuleName) { 7749b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // We do all of our poisoning and unpoisoning within _GLOBAL__I_a. 7759b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany Function *GlobalInit = M.getFunction("_GLOBAL__I_a"); 7769b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // If that function is not present, this TU contains no globals, or they have 7779b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // all been optimized away 7789b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (!GlobalInit) 7799b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return; 7809b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 7819b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Set up the arguments to our poison/unpoison functions. 7829b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany IRBuilder<> IRB(GlobalInit->begin()->getFirstInsertionPt()); 7839b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 7849b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Add a call to poison all external globals before the given function starts. 785ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov Value *ModuleNameAddr = ConstantExpr::getPointerCast(ModuleName, IntptrTy); 786ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov IRB.CreateCall(AsanPoisonGlobals, ModuleNameAddr); 7879b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 7889b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Add calls to unpoison all globals before each return instruction. 7899b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany for (Function::iterator I = GlobalInit->begin(), E = GlobalInit->end(); 7909b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany I != E; ++I) { 7919b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (ReturnInst *RI = dyn_cast<ReturnInst>(I->getTerminator())) { 7929b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany CallInst::Create(AsanUnpoisonGlobals, "", RI); 7939b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany } 7949b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany } 7959b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany} 7969b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 7971416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryanybool AddressSanitizerModule::ShouldInstrumentGlobal(GlobalVariable *G) { 7989b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany Type *Ty = cast<PointerType>(G->getType())->getElementType(); 799324d96b9e265b0fd8bf63a28340910def64e2164Kostya Serebryany DEBUG(dbgs() << "GLOBAL: " << *G << "\n"); 8009b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 80159a4a47a7bea7cc17877c6a3954ad9f8309ff1cbKostya Serebryany if (BL->isIn(*G)) return false; 8029b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (!Ty->isSized()) return false; 8039b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (!G->hasInitializer()) return false; 80451c7c65e32f76ec5a50cdecfe2b4c287c57da127Kostya Serebryany if (GlobalWasGeneratedByAsan(G)) return false; // Our own global. 8059b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Touch only those globals that will not be defined in other modules. 8069b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Don't handle ODR type linkages since other modules may be built w/o asan. 8079b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (G->getLinkage() != GlobalVariable::ExternalLinkage && 8089b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany G->getLinkage() != GlobalVariable::PrivateLinkage && 8099b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany G->getLinkage() != GlobalVariable::InternalLinkage) 8109b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return false; 8119b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Two problems with thread-locals: 8129b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // - The address of the main thread's copy can't be computed at link-time. 8139b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // - Need to poison all copies, not just the main thread's one. 8149b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (G->isThreadLocal()) 8159b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return false; 8169b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // For now, just ignore this Alloca if the alignment is large. 817b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany if (G->getAlignment() > RedzoneSize()) return false; 8189b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 8199b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Ignore all the globals with the names starting with "\01L_OBJC_". 8209b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Many of those are put into the .cstring section. The linker compresses 8219b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // that section by removing the spare \0s after the string terminator, so 8229b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // our redzones get broken. 8239b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if ((G->getName().find("\01L_OBJC_") == 0) || 8249b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany (G->getName().find("\01l_OBJC_") == 0)) { 8259b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany DEBUG(dbgs() << "Ignoring \\01L_OBJC_* global: " << *G); 8269b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return false; 8279b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany } 8289b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 8299b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (G->hasSection()) { 8309b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany StringRef Section(G->getSection()); 8319b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Ignore the globals from the __OBJC section. The ObjC runtime assumes 8329b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // those conform to /usr/lib/objc/runtime.h, so we can't add redzones to 8339b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // them. 8349b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if ((Section.find("__OBJC,") == 0) || 8359b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany (Section.find("__DATA, __objc_") == 0)) { 8369b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany DEBUG(dbgs() << "Ignoring ObjC runtime global: " << *G); 8379b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return false; 8389b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany } 8399b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // See http://code.google.com/p/address-sanitizer/issues/detail?id=32 8409b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Constant CFString instances are compiled in the following way: 8419b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // -- the string buffer is emitted into 8429b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // __TEXT,__cstring,cstring_literals 8439b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // -- the constant NSConstantString structure referencing that buffer 8449b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // is placed into __DATA,__cfstring 8459b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Therefore there's no point in placing redzones into __DATA,__cfstring. 8469b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Moreover, it causes the linker to crash on OS X 10.7 8479b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (Section.find("__DATA,__cfstring") == 0) { 8489b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany DEBUG(dbgs() << "Ignoring CFString: " << *G); 8499b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return false; 8509b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany } 8519b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany } 8529b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 8539b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany return true; 8549b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany} 8559b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 8564684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonovvoid AddressSanitizerModule::initializeCallbacks(Module &M) { 8574684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov IRBuilder<> IRB(*C); 8584684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov // Declare our poisoning and unpoisoning functions. 8594684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov AsanPoisonGlobals = checkInterfaceFunction(M.getOrInsertFunction( 860ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov kAsanPoisonGlobalsName, IRB.getVoidTy(), IntptrTy, NULL)); 8614684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov AsanPoisonGlobals->setLinkage(Function::ExternalLinkage); 8624684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov AsanUnpoisonGlobals = checkInterfaceFunction(M.getOrInsertFunction( 8634684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov kAsanUnpoisonGlobalsName, IRB.getVoidTy(), NULL)); 8644684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov AsanUnpoisonGlobals->setLinkage(Function::ExternalLinkage); 8654684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov // Declare functions that register/unregister globals. 8664684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov AsanRegisterGlobals = checkInterfaceFunction(M.getOrInsertFunction( 8674684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov kAsanRegisterGlobalsName, IRB.getVoidTy(), 8684684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov IntptrTy, IntptrTy, NULL)); 8694684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov AsanRegisterGlobals->setLinkage(Function::ExternalLinkage); 8704684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov AsanUnregisterGlobals = checkInterfaceFunction(M.getOrInsertFunction( 8714684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov kAsanUnregisterGlobalsName, 8724684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov IRB.getVoidTy(), IntptrTy, IntptrTy, NULL)); 8734684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov AsanUnregisterGlobals->setLinkage(Function::ExternalLinkage); 8744684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov} 8754684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov 876800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// This function replaces all global variables with new variables that have 877800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// trailing redzones. It also creates a function that poisons 878800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany// redzones and inserts this function into llvm.global_ctors. 8791416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryanybool AddressSanitizerModule::runOnModule(Module &M) { 8801416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany if (!ClGlobals) return false; 8811416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany TD = getAnalysisIfAvailable<DataLayout>(); 8821416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany if (!TD) 8831416edc30adbd53b2be863f7f3de56de4a4c9d0aKostya Serebryany return false; 884405515d55f470d04ef75f653b7f1994329c9066bPeter Collingbourne BL.reset(new SpecialCaseList(BlacklistFile)); 885d6f62c8da5aa4f3388cec1542309ffa623cac601Alexey Samsonov if (BL->isIn(M)) return false; 886b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany C = &(M.getContext()); 88719cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov int LongSize = TD->getPointerSizeInBits(); 88819cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov IntptrTy = Type::getIntNTy(*C, LongSize); 88911af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov Mapping = getShadowMapping(M, LongSize, ZeroBaseShadow); 8904684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov initializeCallbacks(M); 8914684858624d7ffe82379783e9b678227d5e0b515Alexey Samsonov DynamicallyInitializedGlobals.Init(M); 892b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany 893800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallVector<GlobalVariable *, 16> GlobalsToChange; 894800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 8959b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany for (Module::GlobalListType::iterator G = M.global_begin(), 8969b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany E = M.global_end(); G != E; ++G) { 8979b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany if (ShouldInstrumentGlobal(G)) 8989b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany GlobalsToChange.push_back(G); 899800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 900800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 901800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t n = GlobalsToChange.size(); 902800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (n == 0) return false; 903800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 904800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // A global is described by a structure 905800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // size_t beg; 906800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // size_t size; 907800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // size_t size_with_redzone; 908800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // const char *name; 909086a472dbed9911f83add781e020cb49c89829d0Kostya Serebryany // const char *module_name; 9109b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // size_t has_dynamic_init; 911800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // We initialize an array of such structures and pass it to a run-time call. 912800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StructType *GlobalStructTy = StructType::get(IntptrTy, IntptrTy, 9139b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany IntptrTy, IntptrTy, 914086a472dbed9911f83add781e020cb49c89829d0Kostya Serebryany IntptrTy, IntptrTy, NULL); 9159b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany SmallVector<Constant *, 16> Initializers(n), DynamicInit; 916800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 917b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany 918b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany Function *CtorFunc = M.getFunction(kAsanModuleCtorName); 919b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany assert(CtorFunc); 920b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany IRBuilder<> IRB(CtorFunc->getEntryBlock().getTerminator()); 921800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 922ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov bool HasDynamicallyInitializedGlobals = false; 9239b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 924086a472dbed9911f83add781e020cb49c89829d0Kostya Serebryany GlobalVariable *ModuleName = createPrivateGlobalForString( 925086a472dbed9911f83add781e020cb49c89829d0Kostya Serebryany M, M.getModuleIdentifier()); 926ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov // We shouldn't merge same module names, as this string serves as unique 927ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov // module ID in runtime. 928ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov ModuleName->setUnnamedAddr(false); 929086a472dbed9911f83add781e020cb49c89829d0Kostya Serebryany 930800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0; i < n; i++) { 93129f975f8ffda1f5d78cbf2530c2316abef11aa70Kostya Serebryany static const uint64_t kMaxGlobalRedzone = 1 << 18; 932800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalVariable *G = GlobalsToChange[i]; 933800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany PointerType *PtrTy = cast<PointerType>(G->getType()); 934800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *Ty = PtrTy->getElementType(); 935208a4ff2b56f453910bb817540f34b8169f7702aKostya Serebryany uint64_t SizeInBytes = TD->getTypeAllocSize(Ty); 93629f975f8ffda1f5d78cbf2530c2316abef11aa70Kostya Serebryany uint64_t MinRZ = RedzoneSize(); 93763f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany // MinRZ <= RZ <= kMaxGlobalRedzone 93863f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany // and trying to make RZ to be ~ 1/4 of SizeInBytes. 93929f975f8ffda1f5d78cbf2530c2316abef11aa70Kostya Serebryany uint64_t RZ = std::max(MinRZ, 94063f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany std::min(kMaxGlobalRedzone, 94163f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany (SizeInBytes / MinRZ / 4) * MinRZ)); 94263f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany uint64_t RightRedzoneSize = RZ; 94363f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany // Round up to MinRZ 94463f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany if (SizeInBytes % MinRZ) 94563f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany RightRedzoneSize += MinRZ - (SizeInBytes % MinRZ); 94663f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany assert(((RightRedzoneSize + SizeInBytes) % MinRZ) == 0); 947800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *RightRedZoneTy = ArrayType::get(IRB.getInt8Ty(), RightRedzoneSize); 9489b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Determine whether this global should be poisoned in initialization. 949ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany bool GlobalHasDynamicInitializer = 950ca23d43084c45a7d6f4371d62f45be044650ce38Kostya Serebryany DynamicallyInitializedGlobals.Contains(G); 95159a4a47a7bea7cc17877c6a3954ad9f8309ff1cbKostya Serebryany // Don't check initialization order if this global is blacklisted. 95246e11c4c97fe1c424241e4098801456303a5c86ePeter Collingbourne GlobalHasDynamicInitializer &= !BL->isIn(*G, "init"); 953800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 954800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StructType *NewTy = StructType::get(Ty, RightRedZoneTy, NULL); 955800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Constant *NewInitializer = ConstantStruct::get( 956800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NewTy, G->getInitializer(), 957800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Constant::getNullValue(RightRedZoneTy), NULL); 958800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 959086a472dbed9911f83add781e020cb49c89829d0Kostya Serebryany GlobalVariable *Name = createPrivateGlobalForString(M, G->getName()); 960800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 961800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Create a new global variable with enough space for a redzone. 962800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalVariable *NewGlobal = new GlobalVariable( 963800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany M, NewTy, G->isConstant(), G->getLinkage(), 964ce718ff9f42c7da092eaa01dd0242e8d5ba84713Hans Wennborg NewInitializer, "", G, G->getThreadLocalMode()); 965800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NewGlobal->copyAttributesFrom(G); 96663f0846f1eb43332a08811d332b813276b727eb6Kostya Serebryany NewGlobal->setAlignment(MinRZ); 967800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 968800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Indices2[2]; 969800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Indices2[0] = IRB.getInt32(0); 970800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Indices2[1] = IRB.getInt32(0); 971800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 972800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany G->replaceAllUsesWith( 973f1639abf1aaba1448f719f595156cd0f4cd560ccKostya Serebryany ConstantExpr::getGetElementPtr(NewGlobal, Indices2, true)); 974800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NewGlobal->takeName(G); 975800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany G->eraseFromParent(); 976800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 977800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Initializers[i] = ConstantStruct::get( 978800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalStructTy, 979800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantExpr::getPointerCast(NewGlobal, IntptrTy), 980800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, SizeInBytes), 981800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, SizeInBytes + RightRedzoneSize), 982800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantExpr::getPointerCast(Name, IntptrTy), 983086a472dbed9911f83add781e020cb49c89829d0Kostya Serebryany ConstantExpr::getPointerCast(ModuleName, IntptrTy), 9849b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany ConstantInt::get(IntptrTy, GlobalHasDynamicInitializer), 985800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NULL); 9869b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 9879b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Populate the first and last globals declared in this TU. 988ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov if (CheckInitOrder && GlobalHasDynamicInitializer) 989ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov HasDynamicallyInitializedGlobals = true; 9909b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany 991324d96b9e265b0fd8bf63a28340910def64e2164Kostya Serebryany DEBUG(dbgs() << "NEW GLOBAL: " << *NewGlobal << "\n"); 992800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 993800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 994800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ArrayType *ArrayOfGlobalStructTy = ArrayType::get(GlobalStructTy, n); 995800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany GlobalVariable *AllGlobals = new GlobalVariable( 996800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany M, ArrayOfGlobalStructTy, false, GlobalVariable::PrivateLinkage, 997800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantArray::get(ArrayOfGlobalStructTy, Initializers), ""); 998800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 9999b9f87a87ac1b373c4c6a70904315bebbd01c50cKostya Serebryany // Create calls for poisoning before initializers run and unpoisoning after. 1000ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov if (CheckInitOrder && HasDynamicallyInitializedGlobals) 1001ca825ea24de2f3d819845ee01796dc6c7a45170dAlexey Samsonov createInitializerPoisonCalls(M, ModuleName); 1002800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateCall2(AsanRegisterGlobals, 1003800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreatePointerCast(AllGlobals, IntptrTy), 1004800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, n)); 1005800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 10067bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany // We also need to unregister globals at the end, e.g. when a shared library 10077bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany // gets closed. 10087bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany Function *AsanDtorFunction = Function::Create( 10097bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany FunctionType::get(Type::getVoidTy(*C), false), 10107bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany GlobalValue::InternalLinkage, kAsanModuleDtorName, &M); 10117bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany BasicBlock *AsanDtorBB = BasicBlock::Create(*C, "", AsanDtorFunction); 10127bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany IRBuilder<> IRB_Dtor(ReturnInst::Create(*C, AsanDtorBB)); 10137bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany IRB_Dtor.CreateCall2(AsanUnregisterGlobals, 10147bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany IRB.CreatePointerCast(AllGlobals, IntptrTy), 10157bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany ConstantInt::get(IntptrTy, n)); 10167bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany appendToGlobalDtors(M, AsanDtorFunction, kAsanCtorAndCtorPriority); 10177bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany 1018800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany DEBUG(dbgs() << M); 1019800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return true; 1020800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 1021800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 10228b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryanyvoid AddressSanitizer::initializeCallbacks(Module &M) { 10238b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany IRBuilder<> IRB(*C); 10249db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany // Create __asan_report* callbacks. 10259db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany for (size_t AccessIsWrite = 0; AccessIsWrite <= 1; AccessIsWrite++) { 10269db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany for (size_t AccessSizeIndex = 0; AccessSizeIndex < kNumberOfAccessSizes; 10279db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany AccessSizeIndex++) { 10289db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany // IsWrite and TypeSize are encoded in the function name. 10299db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany std::string FunctionName = std::string(kAsanReportErrorTemplate) + 10309db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany (AccessIsWrite ? "store" : "load") + itostr(1 << AccessSizeIndex); 10314f0c69623c10a3a49f6926fd53694ee532e06a85Kostya Serebryany // If we are merging crash callbacks, they have two parameters. 10327846c1c851a53a8280f9d8ed57cd98d82c742551Kostya Serebryany AsanErrorCallback[AccessIsWrite][AccessSizeIndex] = 10337846c1c851a53a8280f9d8ed57cd98d82c742551Kostya Serebryany checkInterfaceFunction(M.getOrInsertFunction( 10347846c1c851a53a8280f9d8ed57cd98d82c742551Kostya Serebryany FunctionName, IRB.getVoidTy(), IntptrTy, NULL)); 10359db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany } 10369db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany } 10376ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany AsanErrorCallbackSized[0] = checkInterfaceFunction(M.getOrInsertFunction( 10386ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany kAsanReportLoadN, IRB.getVoidTy(), IntptrTy, IntptrTy, NULL)); 10396ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany AsanErrorCallbackSized[1] = checkInterfaceFunction(M.getOrInsertFunction( 10406ecccdbb2bf24a011b9c8ecbdd39be5a02269670Kostya Serebryany kAsanReportStoreN, IRB.getVoidTy(), IntptrTy, IntptrTy, NULL)); 1041ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany 1042ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany AsanHandleNoReturnFunc = checkInterfaceFunction(M.getOrInsertFunction( 1043ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany kAsanHandleNoReturnName, IRB.getVoidTy(), NULL)); 1044f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany // We insert an empty inline asm after __asan_report* to avoid callback merge. 1045f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany EmptyAsm = InlineAsm::get(FunctionType::get(IRB.getVoidTy(), false), 1046f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany StringRef(""), StringRef(""), 1047f7b08226eb44458f6f38cbeaca527028803c725aKostya Serebryany /*hasSideEffects=*/true); 10488b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany} 10498b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany 105019cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonovvoid AddressSanitizer::emitShadowMapping(Module &M, IRBuilder<> &IRB) const { 105111af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov // Tell the values of mapping offset and scale to the run-time. 105211af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov GlobalValue *asan_mapping_offset = 105311af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov new GlobalVariable(M, IntptrTy, true, GlobalValue::LinkOnceODRLinkage, 105411af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov ConstantInt::get(IntptrTy, Mapping.Offset), 105511af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov kAsanMappingOffsetName); 105611af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov // Read the global, otherwise it may be optimized away. 105711af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov IRB.CreateLoad(asan_mapping_offset, true); 105811af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov 105911af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov GlobalValue *asan_mapping_scale = 106011af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov new GlobalVariable(M, IntptrTy, true, GlobalValue::LinkOnceODRLinkage, 106111af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov ConstantInt::get(IntptrTy, Mapping.Scale), 106211af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov kAsanMappingScaleName); 106311af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov // Read the global, otherwise it may be optimized away. 106411af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov IRB.CreateLoad(asan_mapping_scale, true); 106519cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov} 106619cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov 10678b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany// virtual 10688b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryanybool AddressSanitizer::doInitialization(Module &M) { 10698b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany // Initialize the private fields. No one has accessed them before. 10708b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany TD = getAnalysisIfAvailable<DataLayout>(); 10718b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany 10728b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany if (!TD) 10738b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany return false; 1074405515d55f470d04ef75f653b7f1994329c9066bPeter Collingbourne BL.reset(new SpecialCaseList(BlacklistFile)); 10758b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany DynamicallyInitializedGlobals.Init(M); 10768b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany 10778b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany C = &(M.getContext()); 10788b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany LongSize = TD->getPointerSizeInBits(); 10798b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany IntptrTy = Type::getIntNTy(*C, LongSize); 10808b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany 10818b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany AsanCtorFunction = Function::Create( 10828b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany FunctionType::get(Type::getVoidTy(*C), false), 10838b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany GlobalValue::InternalLinkage, kAsanModuleCtorName, &M); 10848b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany BasicBlock *AsanCtorBB = BasicBlock::Create(*C, "", AsanCtorFunction); 10858b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany // call __asan_init in the module ctor. 10868b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany IRBuilder<> IRB(ReturnInst::Create(*C, AsanCtorBB)); 10878b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany AsanInitFunction = checkInterfaceFunction( 10888b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany M.getOrInsertFunction(kAsanInitName, IRB.getVoidTy(), NULL)); 10898b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany AsanInitFunction->setLinkage(Function::ExternalLinkage); 10908b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany IRB.CreateCall(AsanInitFunction); 10919db5b5ffa9fccd5c7f1f39a3e9aa66cc4a5eedc1Kostya Serebryany 109211af9a873f9e1409a422ab31e22729368805afafAlexey Samsonov Mapping = getShadowMapping(M, LongSize, ZeroBaseShadow); 109319cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov emitShadowMapping(M, IRB); 1094800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 10957bcfc9950bac0f411f9671e8d6ce483bd219727eKostya Serebryany appendToGlobalCtors(M, AsanCtorFunction, kAsanCtorAndCtorPriority); 1096ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany return true; 1097ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany} 1098ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany 1099a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryanybool AddressSanitizer::maybeInsertAsanInitAtFunctionEntry(Function &F) { 1100a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // For each NSObject descendant having a +load method, this method is invoked 1101a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // by the ObjC runtime before any of the static constructors is called. 1102a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // Therefore we need to instrument such methods with a call to __asan_init 1103a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // at the beginning in order to initialize our runtime before any access to 1104a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // the shadow memory. 1105a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // We cannot just ignore these methods, because they may call other 1106a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany // instrumented functions. 1107a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany if (F.getName().find(" load]") != std::string::npos) { 1108a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany IRBuilder<> IRB(F.begin()->begin()); 1109a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany IRB.CreateCall(AsanInitFunction); 1110a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany return true; 1111a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany } 1112a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany return false; 1113a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany} 1114a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany 1115ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryanybool AddressSanitizer::runOnFunction(Function &F) { 1116800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (BL->isIn(F)) return false; 1117800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (&F == AsanCtorFunction) return false; 11183797adb94fdc6b747cb0e97a64b15b931f2533b8Kostya Serebryany if (F.getLinkage() == GlobalValue::AvailableExternallyLinkage) return false; 1119324d96b9e265b0fd8bf63a28340910def64e2164Kostya Serebryany DEBUG(dbgs() << "ASAN instrumenting:\n" << F << "\n"); 11208b390ffbfdd52a23a45a21de99aa1c31f3ce623fKostya Serebryany initializeCallbacks(*F.getParent()); 1121a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany 11228eec41fc778e99d42172a7f6de76faa43a6d8847Kostya Serebryany // If needed, insert __asan_init before checking for SanitizeAddress attr. 1123a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany maybeInsertAsanInitAtFunctionEntry(F); 1124a1a8a323f43a95620fc4c6b5aad8d5ff5e5eb590Kostya Serebryany 112520985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany if (!F.hasFnAttribute(Attribute::SanitizeAddress)) 11266765834754cbb3cb0f15b4b15e98c5e73fa50066Bill Wendling return false; 1127800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1128800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!ClDebugFunc.empty() && ClDebugFunc != F.getName()) 1129800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return false; 11306765834754cbb3cb0f15b4b15e98c5e73fa50066Bill Wendling 11316765834754cbb3cb0f15b4b15e98c5e73fa50066Bill Wendling // We want to instrument every address only once per basic block (unless there 11326765834754cbb3cb0f15b4b15e98c5e73fa50066Bill Wendling // are calls between uses). 1133800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallSet<Value*, 16> TempsToInstrument; 1134800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallVector<Instruction*, 16> ToInstrument; 113595e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany SmallVector<Instruction*, 8> NoReturnCalls; 113620985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany int NumAllocas = 0; 1137e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany bool IsWrite; 1138800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1139800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Fill the set of memory operations to instrument. 1140800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (Function::iterator FI = F.begin(), FE = F.end(); 1141800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany FI != FE; ++FI) { 1142800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TempsToInstrument.clear(); 1143324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany int NumInsnsPerBB = 0; 1144800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); 1145800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BI != BE; ++BI) { 1146bcb55ce3862bbbedac4e09d7099c9e0efc434e4bKostya Serebryany if (LooksLikeCodeInBug11395(BI)) return false; 1147e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (Value *Addr = isInterestingMemoryAccess(BI, &IsWrite)) { 1148800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClOpt && ClOptSameTemp) { 1149800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (!TempsToInstrument.insert(Addr)) 1150800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany continue; // We've seen this temp in the current BB. 1151800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1152800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else if (isa<MemIntrinsic>(BI) && ClMemIntrin) { 1153800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // ok, take it. 1154800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else { 115520985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany if (isa<AllocaInst>(BI)) 115620985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany NumAllocas++; 11571479c9bb392325688b72e5829bbb7939c4a079a4Kostya Serebryany CallSite CS(BI); 11581479c9bb392325688b72e5829bbb7939c4a079a4Kostya Serebryany if (CS) { 1159800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // A call inside BB. 1160800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany TempsToInstrument.clear(); 11611479c9bb392325688b72e5829bbb7939c4a079a4Kostya Serebryany if (CS.doesNotReturn()) 11621479c9bb392325688b72e5829bbb7939c4a079a4Kostya Serebryany NoReturnCalls.push_back(CS.getInstruction()); 1163800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1164800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany continue; 1165800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1166800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ToInstrument.push_back(BI); 1167324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany NumInsnsPerBB++; 1168324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany if (NumInsnsPerBB >= ClMaxInsnsToInstrumentPerBB) 1169324cbb89f2759fb9ad347bd2af4631e50c39c8f3Kostya Serebryany break; 1170800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1171800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1172800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 117320985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany Function *UninstrumentedDuplicate = 0; 117420985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany bool LikelyToInstrument = 117520985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany !NoReturnCalls.empty() || !ToInstrument.empty() || (NumAllocas > 0); 117620985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany if (ClKeepUninstrumented && LikelyToInstrument) { 117720985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany ValueToValueMapTy VMap; 117820985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany UninstrumentedDuplicate = CloneFunction(&F, VMap, false); 117920985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany UninstrumentedDuplicate->removeFnAttr(Attribute::SanitizeAddress); 118020985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany UninstrumentedDuplicate->setName("NOASAN_" + F.getName()); 118120985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany F.getParent()->getFunctionList().push_back(UninstrumentedDuplicate); 118220985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany } 118320985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany 1184800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Instrument. 1185800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany int NumInstrumented = 0; 1186800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0, n = ToInstrument.size(); i != n; i++) { 1187800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *Inst = ToInstrument[i]; 1188800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ClDebugMin < 0 || ClDebugMax < 0 || 1189800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany (NumInstrumented >= ClDebugMin && NumInstrumented <= ClDebugMax)) { 1190e6cf2e0bd09544eeb69665deb908d264e62a71c2Kostya Serebryany if (isInterestingMemoryAccess(Inst, &IsWrite)) 1191ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany instrumentMop(Inst); 1192800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany else 1193ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany instrumentMemIntrinsic(cast<MemIntrinsic>(Inst)); 1194800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1195800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany NumInstrumented++; 1196800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1197800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 119859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov FunctionStackPoisoner FSP(F, *this); 119959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov bool ChangedStack = FSP.runOnFunction(); 120095e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany 120195e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany // We must unpoison the stack before every NoReturn call (throw, _exit, etc). 120295e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany // See e.g. http://code.google.com/p/address-sanitizer/issues/detail?id=37 120395e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany for (size_t i = 0, n = NoReturnCalls.size(); i != n; i++) { 120495e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany Instruction *CI = NoReturnCalls[i]; 120595e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany IRBuilder<> IRB(CI); 1206ee4edeccabe1854ee895f52d4ac5588bd5f40c80Kostya Serebryany IRB.CreateCall(AsanHandleNoReturnFunc); 120795e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany } 120895e3cf44a9d4672655dee3bd558bfeefa631dd55Kostya Serebryany 120920985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany bool res = NumInstrumented > 0 || ChangedStack || !NoReturnCalls.empty(); 121020985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany DEBUG(dbgs() << "ASAN done instrumenting: " << res << " " << F << "\n"); 121120985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany 121220985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany if (ClKeepUninstrumented) { 121320985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany if (!res) { 121420985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany // No instrumentation is done, no need for the duplicate. 121520985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany if (UninstrumentedDuplicate) 121620985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany UninstrumentedDuplicate->eraseFromParent(); 121720985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany } else { 121820985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany // The function was instrumented. We must have the duplicate. 121920985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany assert(UninstrumentedDuplicate); 122020985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany UninstrumentedDuplicate->setSection("NOASAN"); 122120985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany assert(!F.hasSection()); 122220985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany F.setSection("ASAN"); 122320985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany } 122420985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany } 122520985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany 122620985711c76b8799d689a9c0e416b68896333c23Kostya Serebryany return res; 1227800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 1228800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1229800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic uint64_t ValueForPoison(uint64_t PoisonByte, size_t ShadowRedzoneSize) { 1230800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ShadowRedzoneSize == 1) return PoisonByte; 1231800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ShadowRedzoneSize == 2) return (PoisonByte << 8) + PoisonByte; 1232800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (ShadowRedzoneSize == 4) 1233800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany return (PoisonByte << 24) + (PoisonByte << 16) + 1234800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany (PoisonByte << 8) + (PoisonByte); 1235858143816d43e58b17bfd11cb1b57afbd7f0f893Craig Topper llvm_unreachable("ShadowRedzoneSize is either 1, 2 or 4"); 1236800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 1237800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1238800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryanystatic void PoisonShadowPartialRightRedzone(uint8_t *Shadow, 1239800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t Size, 1240b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany size_t RZSize, 1241800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany size_t ShadowGranularity, 1242800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint8_t Magic) { 1243b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany for (size_t i = 0; i < RZSize; 1244800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany i+= ShadowGranularity, Shadow++) { 1245800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (i + ShadowGranularity <= Size) { 1246800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany *Shadow = 0; // fully addressable 1247800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else if (i >= Size) { 1248800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany *Shadow = Magic; // unaddressable 1249800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } else { 1250800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany *Shadow = Size - i; // first Size-i bytes are addressable 1251800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1252800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1253800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 1254800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 125559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// Workaround for bug 11395: we don't want to instrument stack in functions 125659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// with large assembly blobs (32-bit only), otherwise reg alloc may crash. 125759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// FIXME: remove once the bug 11395 is fixed. 125859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonovbool AddressSanitizer::LooksLikeCodeInBug11395(Instruction *I) { 125959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov if (LongSize != 32) return false; 126059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov CallInst *CI = dyn_cast<CallInst>(I); 126159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov if (!CI || !CI->isInlineAsm()) return false; 126259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov if (CI->getNumArgOperands() <= 5) return false; 126359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov // We have inline assembly with quite a few arguments. 126459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov return true; 126559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov} 126659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 126759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonovvoid FunctionStackPoisoner::initializeCallbacks(Module &M) { 126859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov IRBuilder<> IRB(*C); 126959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov AsanStackMallocFunc = checkInterfaceFunction(M.getOrInsertFunction( 127059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov kAsanStackMallocName, IntptrTy, IntptrTy, IntptrTy, NULL)); 127159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov AsanStackFreeFunc = checkInterfaceFunction(M.getOrInsertFunction( 127259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov kAsanStackFreeName, IRB.getVoidTy(), 127359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov IntptrTy, IntptrTy, IntptrTy, NULL)); 127459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov AsanPoisonStackMemoryFunc = checkInterfaceFunction(M.getOrInsertFunction( 127559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov kAsanPoisonStackMemoryName, IRB.getVoidTy(), IntptrTy, IntptrTy, NULL)); 127659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov AsanUnpoisonStackMemoryFunc = checkInterfaceFunction(M.getOrInsertFunction( 127759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov kAsanUnpoisonStackMemoryName, IRB.getVoidTy(), IntptrTy, IntptrTy, NULL)); 127859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov} 127959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 128059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonovvoid FunctionStackPoisoner::poisonRedZones( 128159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov const ArrayRef<AllocaInst*> &AllocaVec, IRBuilder<> IRB, Value *ShadowBase, 128259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov bool DoPoison) { 128319cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov size_t ShadowRZSize = RedzoneSize() >> Mapping.Scale; 1284800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(ShadowRZSize >= 1 && ShadowRZSize <= 4); 1285800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *RZTy = Type::getIntNTy(*C, ShadowRZSize * 8); 1286800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *RZPtrTy = PointerType::get(RZTy, 0); 1287800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1288800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *PoisonLeft = ConstantInt::get(RZTy, 1289800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ValueForPoison(DoPoison ? kAsanStackLeftRedzoneMagic : 0LL, ShadowRZSize)); 1290800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *PoisonMid = ConstantInt::get(RZTy, 1291800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ValueForPoison(DoPoison ? kAsanStackMidRedzoneMagic : 0LL, ShadowRZSize)); 1292800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *PoisonRight = ConstantInt::get(RZTy, 1293800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ValueForPoison(DoPoison ? kAsanStackRightRedzoneMagic : 0LL, ShadowRZSize)); 1294800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1295800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // poison the first red zone. 1296800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(PoisonLeft, IRB.CreateIntToPtr(ShadowBase, RZPtrTy)); 1297800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1298800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // poison all other red zones. 1299b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany uint64_t Pos = RedzoneSize(); 1300800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0, n = AllocaVec.size(); i < n; i++) { 1301800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AllocaInst *AI = AllocaVec[i]; 1302800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t SizeInBytes = getAllocaSizeInBytes(AI); 1303800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t AlignedSize = getAlignedAllocaSize(AI); 1304b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany assert(AlignedSize - SizeInBytes < RedzoneSize()); 1305800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *Ptr = NULL; 1306800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1307800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Pos += AlignedSize; 1308800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1309800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(ShadowBase->getType() == IntptrTy); 1310800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (SizeInBytes < AlignedSize) { 1311800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Poison the partial redzone at right 1312800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Ptr = IRB.CreateAdd( 1313800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ShadowBase, ConstantInt::get(IntptrTy, 131419cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov (Pos >> Mapping.Scale) - ShadowRZSize)); 1315b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany size_t AddressableBytes = RedzoneSize() - (AlignedSize - SizeInBytes); 1316800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint32_t Poison = 0; 1317800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (DoPoison) { 1318800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany PoisonShadowPartialRightRedzone((uint8_t*)&Poison, AddressableBytes, 1319b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany RedzoneSize(), 132019cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov 1ULL << Mapping.Scale, 1321800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany kAsanStackPartialRedzoneMagic); 13223e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany Poison = 13233e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany ASan.TD->isLittleEndian() 13243e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany ? support::endian::byte_swap<uint32_t, support::little>(Poison) 13253e1d45bf44f882f3ee139d452dd50305d831a341Kostya Serebryany : support::endian::byte_swap<uint32_t, support::big>(Poison); 1326800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1327800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *PartialPoison = ConstantInt::get(RZTy, Poison); 1328800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(PartialPoison, IRB.CreateIntToPtr(Ptr, RZPtrTy)); 1329800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1330800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1331800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Poison the full redzone at right. 1332800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Ptr = IRB.CreateAdd(ShadowBase, 133319cd7e9ce28ed7f3326ebcd386eec215ab3763f9Alexey Samsonov ConstantInt::get(IntptrTy, Pos >> Mapping.Scale)); 13341c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov bool LastAlloca = (i == AllocaVec.size() - 1); 13351c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov Value *Poison = LastAlloca ? PoisonRight : PoisonMid; 1336800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(Poison, IRB.CreateIntToPtr(Ptr, RZPtrTy)); 1337800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1338b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany Pos += RedzoneSize(); 1339800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1340800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 1341800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 134259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonovvoid FunctionStackPoisoner::poisonStack() { 134359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov uint64_t LocalStackSize = TotalStackSize + 134459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov (AllocaVec.size() + 1) * RedzoneSize(); 1345800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 134659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov bool DoStackMalloc = ASan.CheckUseAfterReturn 1347800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany && LocalStackSize <= kMaxStackMallocSize; 1348800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 13491c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov assert(AllocaVec.size() > 0); 1350800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *InsBefore = AllocaVec[0]; 1351800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRB(InsBefore); 1352800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1353800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1354800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Type *ByteArrayTy = ArrayType::get(IRB.getInt8Ty(), LocalStackSize); 1355800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AllocaInst *MyAlloca = 1356800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany new AllocaInst(ByteArrayTy, "MyAlloca", InsBefore); 135759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov if (ClRealignStack && StackAlignment < RedzoneSize()) 135859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov StackAlignment = RedzoneSize(); 135959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov MyAlloca->setAlignment(StackAlignment); 1360800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(MyAlloca->isStaticAlloca()); 1361800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *OrigStackBase = IRB.CreatePointerCast(MyAlloca, IntptrTy); 1362800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *LocalStackBase = OrigStackBase; 1363800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1364800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (DoStackMalloc) { 1365800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany LocalStackBase = IRB.CreateCall2(AsanStackMallocFunc, 1366800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, LocalStackSize), OrigStackBase); 1367800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1368800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 13693016056769639878b4f152838f0cf16d2e482339Kostya Serebryany // This string will be parsed by the run-time (DescribeAddressIfStack). 1370800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany SmallString<2048> StackDescriptionStorage; 1371800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany raw_svector_ostream StackDescription(StackDescriptionStorage); 13723016056769639878b4f152838f0cf16d2e482339Kostya Serebryany StackDescription << AllocaVec.size() << " "; 1373800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 13741c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Insert poison calls for lifetime intrinsics for alloca. 13751c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov bool HavePoisonedAllocas = false; 13761c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov for (size_t i = 0, n = AllocaPoisonCallVec.size(); i < n; i++) { 13771c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov const AllocaPoisonCall &APC = AllocaPoisonCallVec[i]; 13781c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov IntrinsicInst *II = APC.InsBefore; 13791c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaInst *AI = findAllocaForValue(II->getArgOperand(1)); 13801c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov assert(AI); 13811c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov IRBuilder<> IRB(II); 13821c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov poisonAlloca(AI, APC.Size, IRB, APC.DoPoison); 13831c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov HavePoisonedAllocas |= APC.DoPoison; 13841c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov } 13851c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov 1386b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany uint64_t Pos = RedzoneSize(); 1387800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Replace Alloca instructions with base+offset. 1388800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0, n = AllocaVec.size(); i < n; i++) { 1389800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany AllocaInst *AI = AllocaVec[i]; 1390800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t SizeInBytes = getAllocaSizeInBytes(AI); 1391800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StringRef Name = AI->getName(); 1392800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany StackDescription << Pos << " " << SizeInBytes << " " 1393800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany << Name.size() << " " << Name << " "; 1394800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany uint64_t AlignedSize = getAlignedAllocaSize(AI); 1395b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany assert((AlignedSize % RedzoneSize()) == 0); 1396f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov Value *NewAllocaPtr = IRB.CreateIntToPtr( 1397800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateAdd(LocalStackBase, ConstantInt::get(IntptrTy, Pos)), 1398f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov AI->getType()); 13991afbb517965e29b07cb42e2335d5eadd87de6535Alexey Samsonov replaceDbgDeclareForAlloca(AI, NewAllocaPtr, DIB); 1400f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov AI->replaceAllUsesWith(NewAllocaPtr); 1401b9a12ea0fd92bfdb4c6eb5af333648a618f68686Kostya Serebryany Pos += AlignedSize + RedzoneSize(); 1402800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1403800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany assert(Pos == LocalStackSize); 1404800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 14053016056769639878b4f152838f0cf16d2e482339Kostya Serebryany // The left-most redzone has enough space for at least 4 pointers. 14063016056769639878b4f152838f0cf16d2e482339Kostya Serebryany // Write the Magic value to redzone[0]. 1407800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Value *BasePlus0 = IRB.CreateIntToPtr(LocalStackBase, IntptrPtrTy); 1408800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(ConstantInt::get(IntptrTy, kCurrentStackFrameMagic), 1409800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BasePlus0); 14103016056769639878b4f152838f0cf16d2e482339Kostya Serebryany // Write the frame description constant to redzone[1]. 14113016056769639878b4f152838f0cf16d2e482339Kostya Serebryany Value *BasePlus1 = IRB.CreateIntToPtr( 14123016056769639878b4f152838f0cf16d2e482339Kostya Serebryany IRB.CreateAdd(LocalStackBase, ConstantInt::get(IntptrTy, ASan.LongSize/8)), 14133016056769639878b4f152838f0cf16d2e482339Kostya Serebryany IntptrPtrTy); 14149ce84c1c95c0153a2f33e188ce0db00770425f9eAlexey Samsonov GlobalVariable *StackDescriptionGlobal = 1415a5f54f14435d881b10d8eb65e19fa42af95757e9Kostya Serebryany createPrivateGlobalForString(*F.getParent(), StackDescription.str()); 141659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Value *Description = IRB.CreatePointerCast(StackDescriptionGlobal, 141759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov IntptrTy); 1418800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRB.CreateStore(Description, BasePlus1); 14193016056769639878b4f152838f0cf16d2e482339Kostya Serebryany // Write the PC to redzone[2]. 14203016056769639878b4f152838f0cf16d2e482339Kostya Serebryany Value *BasePlus2 = IRB.CreateIntToPtr( 14213016056769639878b4f152838f0cf16d2e482339Kostya Serebryany IRB.CreateAdd(LocalStackBase, ConstantInt::get(IntptrTy, 14223016056769639878b4f152838f0cf16d2e482339Kostya Serebryany 2 * ASan.LongSize/8)), 14233016056769639878b4f152838f0cf16d2e482339Kostya Serebryany IntptrPtrTy); 14243016056769639878b4f152838f0cf16d2e482339Kostya Serebryany IRB.CreateStore(IRB.CreatePointerCast(&F, IntptrTy), BasePlus2); 1425800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1426800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Poison the stack redzones at the entry. 142759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov Value *ShadowBase = ASan.memToShadow(LocalStackBase, IRB); 142859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov poisonRedZones(AllocaVec, IRB, ShadowBase, true); 1429800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1430800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Unpoison the stack before all ret instructions. 1431800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany for (size_t i = 0, n = RetVec.size(); i < n; i++) { 1432800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany Instruction *Ret = RetVec[i]; 1433800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBuilder<> IRBRet(Ret); 1434800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Mark the current frame as retired. 1435800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBRet.CreateStore(ConstantInt::get(IntptrTy, kRetiredStackFrameMagic), 1436800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany BasePlus0); 1437800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany // Unpoison the stack. 143859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov poisonRedZones(AllocaVec, IRBRet, ShadowBase, false); 1439800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany if (DoStackMalloc) { 1440f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov // In use-after-return mode, mark the whole stack frame unaddressable. 1441800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany IRBRet.CreateCall3(AsanStackFreeFunc, LocalStackBase, 1442800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany ConstantInt::get(IntptrTy, LocalStackSize), 1443800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany OrigStackBase); 1444f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov } else if (HavePoisonedAllocas) { 1445f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov // If we poisoned some allocas in llvm.lifetime analysis, 1446f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov // unpoison whole stack frame now. 1447f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov assert(LocalStackBase == OrigStackBase); 1448f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov poisonAlloca(LocalStackBase, LocalStackSize, IRBRet, false); 1449800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1450800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany } 1451800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany 1452bd0052a0f26f04b8fcf59e8f645e5e33751e1f6eKostya Serebryany // We are done. Remove the old unused alloca instructions. 1453bd0052a0f26f04b8fcf59e8f645e5e33751e1f6eKostya Serebryany for (size_t i = 0, n = AllocaVec.size(); i < n; i++) 1454bd0052a0f26f04b8fcf59e8f645e5e33751e1f6eKostya Serebryany AllocaVec[i]->eraseFromParent(); 1455800e03f59896ef4b26d988f1878370bb5aeec0d8Kostya Serebryany} 1456f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov 145759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonovvoid FunctionStackPoisoner::poisonAlloca(Value *V, uint64_t Size, 145859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov IRBuilder<> IRB, bool DoPoison) { 1459f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov // For now just insert the call to ASan runtime. 1460f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov Value *AddrArg = IRB.CreatePointerCast(V, IntptrTy); 1461f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov Value *SizeArg = ConstantInt::get(IntptrTy, Size); 1462f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov IRB.CreateCall2(DoPoison ? AsanPoisonStackMemoryFunc 1463f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov : AsanUnpoisonStackMemoryFunc, 1464f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov AddrArg, SizeArg); 1465f985f44b13681071e585acb7a5703a2c1c23b6ceAlexey Samsonov} 146659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 146759cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// Handling llvm.lifetime intrinsics for a given %alloca: 146859cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// (1) collect all llvm.lifetime.xxx(%size, %value) describing the alloca. 146959cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// (2) if %size is constant, poison memory for llvm.lifetime.end (to detect 147059cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// invalid accesses) and unpoison it for llvm.lifetime.start (the memory 147159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// could be poisoned by previous llvm.lifetime.end instruction, as the 147259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// variable may go in and out of scope several times, e.g. in loops). 147359cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// (3) if we poisoned at least one %alloca in a function, 147459cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov// unpoison the whole stack frame at function exit. 147559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov 14761c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey SamsonovAllocaInst *FunctionStackPoisoner::findAllocaForValue(Value *V) { 14771c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (AllocaInst *AI = dyn_cast<AllocaInst>(V)) 14781c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // We're intested only in allocas we can handle. 14791c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov return isInterestingAlloca(*AI) ? AI : 0; 14801c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // See if we've already calculated (or started to calculate) alloca for a 14811c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // given value. 14821c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaForValueMapTy::iterator I = AllocaForValue.find(V); 14831c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (I != AllocaForValue.end()) 14841c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov return I->second; 14851c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Store 0 while we're calculating alloca for value V to avoid 14861c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // infinite recursion if the value references itself. 14871c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaForValue[V] = 0; 14881c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaInst *Res = 0; 14891c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (CastInst *CI = dyn_cast<CastInst>(V)) 14901c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov Res = findAllocaForValue(CI->getOperand(0)); 14911c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov else if (PHINode *PN = dyn_cast<PHINode>(V)) { 14921c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { 14931c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov Value *IncValue = PN->getIncomingValue(i); 14941c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // Allow self-referencing phi-nodes. 14951c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (IncValue == PN) continue; 14961c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaInst *IncValueAI = findAllocaForValue(IncValue); 14971c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov // AI for incoming values should exist and should all be equal. 14981c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (IncValueAI == 0 || (Res != 0 && IncValueAI != Res)) 14991c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov return 0; 15001c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov Res = IncValueAI; 150159cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 150259cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov } 15031c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov if (Res != 0) 15041c8b825c4396ad9cd38f713d9e9a51adae1d4c4eAlexey Samsonov AllocaForValue[V] = Res; 150559cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov return Res; 150659cca13a80ed78ccbcdaa9bf20381bd48243f2f1Alexey Samsonov} 1507