[llvm] r318575 - Revert "[asan] Use dynamic shadow on 32-bit Android" and 3 more.
Evgeniy Stepanov via llvm-commits
llvm-commits at lists.llvm.org
Fri Nov 17 16:22:34 PST 2017
Author: eugenis
Date: Fri Nov 17 16:22:34 2017
New Revision: 318575
URL: http://llvm.org/viewvc/llvm-project?rev=318575&view=rev
Log:
Revert "[asan] Use dynamic shadow on 32-bit Android" and 3 more.
Revert the following commits:
r318369 [asan] Fallback to non-ifunc dynamic shadow on android<22.
r318235 [asan] Prevent rematerialization of &__asan_shadow.
r317948 [sanitizer] Remove unnecessary attribute hidden.
r317943 [asan] Use dynamic shadow on 32-bit Android.
MemoryRangeIsAvailable() reads /proc/$PID/maps into an mmap-ed buffer
that may overlap with the address range that we plan to use for the
dynamic shadow mapping. This is causing random startup crashes.
Removed:
llvm/trunk/test/Instrumentation/AddressSanitizer/with-ifunc.ll
Modified:
llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp
Modified: llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp?rev=318575&r1=318574&r2=318575&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/AddressSanitizer.cpp Fri Nov 17 16:22:34 2017
@@ -137,8 +137,8 @@ static const char *const kAsanUnregister
static const char *const kAsanPoisonGlobalsName = "__asan_before_dynamic_init";
static const char *const kAsanUnpoisonGlobalsName = "__asan_after_dynamic_init";
static const char *const kAsanInitName = "__asan_init";
-static const char *const kAsanVersionCheckNamePrefix =
- "__asan_version_mismatch_check_v";
+static const char *const kAsanVersionCheckName =
+ "__asan_version_mismatch_check_v8";
static const char *const kAsanPtrCmp = "__sanitizer_ptr_cmp";
static const char *const kAsanPtrSub = "__sanitizer_ptr_sub";
static const char *const kAsanHandleNoReturnName = "__asan_handle_no_return";
@@ -208,18 +208,6 @@ static cl::opt<bool> ClForceDynamicShado
cl::desc("Load shadow address into a local variable for each function"),
cl::Hidden, cl::init(false));
-static cl::opt<bool>
- ClWithIfunc("asan-with-ifunc",
- cl::desc("Access dynamic shadow through an ifunc global on "
- "platforms that support this"),
- cl::Hidden, cl::init(true));
-
-static cl::opt<bool> ClWithIfuncSuppressRemat(
- "asan-with-ifunc-suppress-remat",
- cl::desc("Suppress rematerialization of dynamic shadow address by passing "
- "it through inline asm in prologue."),
- cl::Hidden, cl::init(true));
-
// This flag limits the number of instructions to be instrumented
// in any given BB. Normally, this should be set to unlimited (INT_MAX),
// but due to http://llvm.org/bugs/show_bug.cgi?id=12652 we temporary
@@ -460,14 +448,10 @@ private:
/// This struct defines the shadow mapping using the rule:
/// shadow = (mem >> Scale) ADD-or-OR Offset.
-/// If InGlobal is true, then
-/// extern char __asan_shadow[];
-/// shadow = (mem >> Scale) + &__asan_shadow
struct ShadowMapping {
int Scale;
uint64_t Offset;
bool OrShadowOffset;
- bool InGlobal;
};
} // end anonymous namespace
@@ -489,7 +473,6 @@ static ShadowMapping getShadowMapping(Tr
TargetTriple.getArch() == Triple::mipsel;
bool IsMIPS64 = TargetTriple.getArch() == Triple::mips64 ||
TargetTriple.getArch() == Triple::mips64el;
- bool IsArmOrThumb = TargetTriple.isARM() || TargetTriple.isThumb();
bool IsAArch64 = TargetTriple.getArch() == Triple::aarch64;
bool IsWindows = TargetTriple.isOSWindows();
bool IsFuchsia = TargetTriple.isOSFuchsia();
@@ -502,8 +485,10 @@ static ShadowMapping getShadowMapping(Tr
}
if (LongSize == 32) {
+ // Android is always PIE, which means that the beginning of the address
+ // space is always available.
if (IsAndroid)
- Mapping.Offset = kDynamicShadowSentinel;
+ Mapping.Offset = 0;
else if (IsMIPS32)
Mapping.Offset = kMIPS32_ShadowOffset32;
else if (IsFreeBSD)
@@ -567,9 +552,6 @@ static ShadowMapping getShadowMapping(Tr
Mapping.OrShadowOffset = !IsAArch64 && !IsPPC64 && !IsSystemZ && !IsPS4CPU &&
!(Mapping.Offset & (Mapping.Offset - 1)) &&
Mapping.Offset != kDynamicShadowSentinel;
- bool IsAndroidWithIfuncSupport =
- IsAndroid && !TargetTriple.isAndroidVersionLT(21);
- Mapping.InGlobal = ClWithIfunc && IsAndroidWithIfuncSupport && IsArmOrThumb;
return Mapping;
}
@@ -692,7 +674,6 @@ private:
DominatorTree *DT;
Function *AsanHandleNoReturnFunc;
Function *AsanPtrCmpFunction, *AsanPtrSubFunction;
- Constant *AsanShadowGlobal;
// These arrays is indexed by AccessIsWrite, Experiment and log2(AccessSize).
Function *AsanErrorCallback[2][2][kNumberOfAccessSizes];
@@ -765,7 +746,6 @@ private:
size_t MinRedzoneSizeForGlobal() const {
return RedzoneSizeForScale(Mapping.Scale);
}
- int GetAsanVersion(const Module &M) const;
GlobalsMetadata GlobalsMD;
bool CompileKernel;
@@ -998,9 +978,8 @@ struct FunctionStackPoisoner : public In
void visitCallSite(CallSite CS) {
Instruction *I = CS.getInstruction();
if (CallInst *CI = dyn_cast<CallInst>(I)) {
- HasNonEmptyInlineAsm |= CI->isInlineAsm() &&
- !CI->isIdenticalTo(EmptyInlineAsm.get()) &&
- I != ASan.LocalDynamicShadow;
+ HasNonEmptyInlineAsm |=
+ CI->isInlineAsm() && !CI->isIdenticalTo(EmptyInlineAsm.get());
HasReturnsTwiceCall |= CI->canReturnTwice();
}
}
@@ -2181,16 +2160,6 @@ bool AddressSanitizerModule::InstrumentG
return true;
}
-int AddressSanitizerModule::GetAsanVersion(const Module &M) const {
- int LongSize = M.getDataLayout().getPointerSizeInBits();
- bool isAndroid = Triple(M.getTargetTriple()).isAndroid();
- int Version = 8;
- // 32-bit Android is one version ahead because of the switch to dynamic
- // shadow.
- Version += (LongSize == 32 && isAndroid);
- return Version;
-}
-
bool AddressSanitizerModule::runOnModule(Module &M) {
C = &(M.getContext());
int LongSize = M.getDataLayout().getPointerSizeInBits();
@@ -2204,11 +2173,9 @@ bool AddressSanitizerModule::runOnModule
// Create a module constructor. A destructor is created lazily because not all
// platforms, and not all modules need it.
- std::string VersionCheckName =
- kAsanVersionCheckNamePrefix + std::to_string(GetAsanVersion(M));
std::tie(AsanCtorFunction, std::ignore) = createSanitizerCtorAndInitFunctions(
M, kAsanModuleCtorName, kAsanInitName, /*InitArgTypes=*/{},
- /*InitArgs=*/{}, VersionCheckName);
+ /*InitArgs=*/{}, kAsanVersionCheckName);
bool CtorComdat = true;
bool Changed = false;
@@ -2307,9 +2274,6 @@ void AddressSanitizer::initializeCallbac
EmptyAsm = InlineAsm::get(FunctionType::get(IRB.getVoidTy(), false),
StringRef(""), StringRef(""),
/*hasSideEffects=*/true);
- if (Mapping.InGlobal)
- AsanShadowGlobal = M.getOrInsertGlobal("__asan_shadow",
- ArrayType::get(IRB.getInt8Ty(), 0));
}
// virtual
@@ -2355,25 +2319,9 @@ void AddressSanitizer::maybeInsertDynami
return;
IRBuilder<> IRB(&F.front().front());
- if (Mapping.InGlobal) {
- if (ClWithIfuncSuppressRemat) {
- // An empty inline asm with input reg == output reg.
- // An opaque pointer-to-int cast, basically.
- InlineAsm *Asm = InlineAsm::get(
- FunctionType::get(IntptrTy, {AsanShadowGlobal->getType()}, false),
- StringRef(""), StringRef("=r,0"),
- /*hasSideEffects=*/false);
- LocalDynamicShadow =
- IRB.CreateCall(Asm, {AsanShadowGlobal}, ".asan.shadow");
- } else {
- LocalDynamicShadow =
- IRB.CreatePointerCast(AsanShadowGlobal, IntptrTy, ".asan.shadow");
- }
- } else {
- Value *GlobalDynamicAddress = F.getParent()->getOrInsertGlobal(
- kAsanShadowMemoryDynamicAddress, IntptrTy);
- LocalDynamicShadow = IRB.CreateLoad(GlobalDynamicAddress);
- }
+ Value *GlobalDynamicAddress = F.getParent()->getOrInsertGlobal(
+ kAsanShadowMemoryDynamicAddress, IntptrTy);
+ LocalDynamicShadow = IRB.CreateLoad(GlobalDynamicAddress);
}
void AddressSanitizer::markEscapedLocalAllocas(Function &F) {
Removed: llvm/trunk/test/Instrumentation/AddressSanitizer/with-ifunc.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/AddressSanitizer/with-ifunc.ll?rev=318574&view=auto
==============================================================================
--- llvm/trunk/test/Instrumentation/AddressSanitizer/with-ifunc.ll (original)
+++ llvm/trunk/test/Instrumentation/AddressSanitizer/with-ifunc.ll (removed)
@@ -1,47 +0,0 @@
-; Test -asan-with-ifunc flag.
-;
-; RUN: opt -asan -asan-module -S -asan-with-ifunc=0 < %s | \
-; RUN: FileCheck %s --check-prefixes=CHECK,CHECK-NOIFUNC
-; RUN: opt -asan -asan-module -S -asan-with-ifunc=1 -asan-with-ifunc-suppress-remat=0 < %s | \
-; RUN: FileCheck %s --check-prefixes=CHECK,CHECK-IFUNC
-; RUN: opt -asan -asan-module -S -asan-with-ifunc=1 -asan-with-ifunc-suppress-remat=1 < %s | \
-; RUN: FileCheck %s --check-prefixes=CHECK,CHECK-IFUNC-NOREMAT
-
-; Pre-Lollipop Android does not support ifunc.
-; RUN: opt -asan -asan-module -S -asan-with-ifunc=1 -asan-with-ifunc-suppress-remat=0 -mtriple=armv7-linux-android20 < %s | \
-; RUN: FileCheck %s --check-prefixes=CHECK,CHECK-NOIFUNC
-; RUN: opt -asan -asan-module -S -asan-with-ifunc=1 -asan-with-ifunc-suppress-remat=0 -mtriple=armv7-linux-android < %s | \
-; RUN: FileCheck %s --check-prefixes=CHECK,CHECK-NOIFUNC
-; RUN: opt -asan -asan-module -S -asan-with-ifunc=1 -asan-with-ifunc-suppress-remat=0 -mtriple=armv7-linux-android21 < %s | \
-; RUN: FileCheck %s --check-prefixes=CHECK,CHECK-IFUNC
-
-target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
-target triple = "armv7--linux-android22"
-
-; CHECK-IFUNC: @__asan_shadow = external global [0 x i8]
-; CHECK-NOIFUNC: @__asan_shadow_memory_dynamic_address = external global i32
-
-define i32 @test_load(i32* %a) sanitize_address {
-; First instrumentation in the function must be to load the dynamic shadow
-; address into a local variable.
-; CHECK-LABEL: @test_load
-; CHECK: entry:
-
-; CHECK-IFUNC-NEXT: %[[A:[^ ]*]] = ptrtoint i32* %a to i32
-; CHECK-IFUNC-NEXT: %[[B:[^ ]*]] = lshr i32 %[[A]], 3
-; CHECK-IFUNC-NEXT: %[[C:[^ ]*]] = add i32 %[[B]], ptrtoint ([0 x i8]* @__asan_shadow to i32)
-
-; CHECK-IFUNC-NOREMAT-NEXT: %[[S:[^ ]*]] = call i32 asm "", "=r,0"([0 x i8]* @__asan_shadow)
-; CHECK-IFUNC-NOREMAT-NEXT: %[[A:[^ ]*]] = ptrtoint i32* %a to i32
-; CHECK-IFUNC-NOREMAT-NEXT: %[[B:[^ ]*]] = lshr i32 %[[A]], 3
-; CHECK-IFUNC-NOREMAT-NEXT: %[[C:[^ ]*]] = add i32 %[[B]], %[[S]]
-
-; CHECK-NOIFUNC-NEXT: %[[SHADOW:[^ ]*]] = load i32, i32* @__asan_shadow_memory_dynamic_address
-; CHECK-NOIFUNC-NEXT: %[[A:[^ ]*]] = ptrtoint i32* %a to i32
-; CHECK-NOIFUNC-NEXT: %[[B:[^ ]*]] = lshr i32 %[[A]], 3
-; CHECK-NOIFUNC-NEXT: %[[C:[^ ]*]] = add i32 %[[B]], %[[SHADOW]]
-
-entry:
- %x = load i32, i32* %a, align 4
- ret i32 %x
-}
More information about the llvm-commits
mailing list