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authorpatrick <patrick@openbsd.org>2020-08-03 14:31:31 +0000
committerpatrick <patrick@openbsd.org>2020-08-03 14:31:31 +0000
commite5dd70708596ae51455a0ffa086a00c5b29f8583 (patch)
tree5d676f27b570bacf71e786c3b5cff3e6f6679b59 /gnu/llvm/clang/lib/CodeGen/SanitizerMetadata.cpp
parentImport LLVM 10.0.0 release including clang, lld and lldb. (diff)
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Import LLVM 10.0.0 release including clang, lld and lldb.
ok hackroom tested by plenty
Diffstat (limited to 'gnu/llvm/clang/lib/CodeGen/SanitizerMetadata.cpp')
-rw-r--r--gnu/llvm/clang/lib/CodeGen/SanitizerMetadata.cpp104
1 files changed, 104 insertions, 0 deletions
diff --git a/gnu/llvm/clang/lib/CodeGen/SanitizerMetadata.cpp b/gnu/llvm/clang/lib/CodeGen/SanitizerMetadata.cpp
new file mode 100644
index 00000000000..24ae6c6e362
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+++ b/gnu/llvm/clang/lib/CodeGen/SanitizerMetadata.cpp
@@ -0,0 +1,104 @@
+//===--- SanitizerMetadata.cpp - Blacklist for sanitizers -----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Class which emits metadata consumed by sanitizer instrumentation passes.
+//
+//===----------------------------------------------------------------------===//
+#include "SanitizerMetadata.h"
+#include "CodeGenModule.h"
+#include "clang/AST/Attr.h"
+#include "clang/AST/Type.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/IR/Constants.h"
+
+using namespace clang;
+using namespace CodeGen;
+
+SanitizerMetadata::SanitizerMetadata(CodeGenModule &CGM) : CGM(CGM) {}
+
+static bool isAsanHwasanOrMemTag(const SanitizerSet& SS) {
+ return SS.hasOneOf(SanitizerKind::Address | SanitizerKind::KernelAddress |
+ SanitizerKind::HWAddress | SanitizerKind::KernelHWAddress |
+ SanitizerKind::MemTag);
+}
+
+void SanitizerMetadata::reportGlobalToASan(llvm::GlobalVariable *GV,
+ SourceLocation Loc, StringRef Name,
+ QualType Ty, bool IsDynInit,
+ bool IsBlacklisted) {
+ if (!isAsanHwasanOrMemTag(CGM.getLangOpts().Sanitize))
+ return;
+ IsDynInit &= !CGM.isInSanitizerBlacklist(GV, Loc, Ty, "init");
+ IsBlacklisted |= CGM.isInSanitizerBlacklist(GV, Loc, Ty);
+
+ llvm::Metadata *LocDescr = nullptr;
+ llvm::Metadata *GlobalName = nullptr;
+ llvm::LLVMContext &VMContext = CGM.getLLVMContext();
+ if (!IsBlacklisted) {
+ // Don't generate source location and global name if it is blacklisted -
+ // it won't be instrumented anyway.
+ LocDescr = getLocationMetadata(Loc);
+ if (!Name.empty())
+ GlobalName = llvm::MDString::get(VMContext, Name);
+ }
+
+ llvm::Metadata *GlobalMetadata[] = {
+ llvm::ConstantAsMetadata::get(GV), LocDescr, GlobalName,
+ llvm::ConstantAsMetadata::get(
+ llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), IsDynInit)),
+ llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
+ llvm::Type::getInt1Ty(VMContext), IsBlacklisted))};
+
+ llvm::MDNode *ThisGlobal = llvm::MDNode::get(VMContext, GlobalMetadata);
+ llvm::NamedMDNode *AsanGlobals =
+ CGM.getModule().getOrInsertNamedMetadata("llvm.asan.globals");
+ AsanGlobals->addOperand(ThisGlobal);
+}
+
+void SanitizerMetadata::reportGlobalToASan(llvm::GlobalVariable *GV,
+ const VarDecl &D, bool IsDynInit) {
+ if (!isAsanHwasanOrMemTag(CGM.getLangOpts().Sanitize))
+ return;
+ std::string QualName;
+ llvm::raw_string_ostream OS(QualName);
+ D.printQualifiedName(OS);
+
+ bool IsBlacklisted = false;
+ for (auto Attr : D.specific_attrs<NoSanitizeAttr>())
+ if (Attr->getMask() & SanitizerKind::Address)
+ IsBlacklisted = true;
+ reportGlobalToASan(GV, D.getLocation(), OS.str(), D.getType(), IsDynInit,
+ IsBlacklisted);
+}
+
+void SanitizerMetadata::disableSanitizerForGlobal(llvm::GlobalVariable *GV) {
+ // For now, just make sure the global is not modified by the ASan
+ // instrumentation.
+ if (isAsanHwasanOrMemTag(CGM.getLangOpts().Sanitize))
+ reportGlobalToASan(GV, SourceLocation(), "", QualType(), false, true);
+}
+
+void SanitizerMetadata::disableSanitizerForInstruction(llvm::Instruction *I) {
+ I->setMetadata(CGM.getModule().getMDKindID("nosanitize"),
+ llvm::MDNode::get(CGM.getLLVMContext(), None));
+}
+
+llvm::MDNode *SanitizerMetadata::getLocationMetadata(SourceLocation Loc) {
+ PresumedLoc PLoc = CGM.getContext().getSourceManager().getPresumedLoc(Loc);
+ if (!PLoc.isValid())
+ return nullptr;
+ llvm::LLVMContext &VMContext = CGM.getLLVMContext();
+ llvm::Metadata *LocMetadata[] = {
+ llvm::MDString::get(VMContext, PLoc.getFilename()),
+ llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
+ llvm::Type::getInt32Ty(VMContext), PLoc.getLine())),
+ llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
+ llvm::Type::getInt32Ty(VMContext), PLoc.getColumn())),
+ };
+ return llvm::MDNode::get(VMContext, LocMetadata);
+}