|  | //===- DWARFVerifier.cpp --------------------------------------------------===// | 
|  | // | 
|  | //                     The LLVM Compiler Infrastructure | 
|  | // | 
|  | // This file is distributed under the University of Illinois Open Source | 
|  | // License. See LICENSE.TXT for details. | 
|  | // | 
|  | //===----------------------------------------------------------------------===// | 
|  |  | 
|  | #include "llvm/DebugInfo/DWARF/DWARFVerifier.h" | 
|  | #include "llvm/ADT/SmallSet.h" | 
|  | #include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h" | 
|  | #include "llvm/DebugInfo/DWARF/DWARFContext.h" | 
|  | #include "llvm/DebugInfo/DWARF/DWARFDebugLine.h" | 
|  | #include "llvm/DebugInfo/DWARF/DWARFDie.h" | 
|  | #include "llvm/DebugInfo/DWARF/DWARFExpression.h" | 
|  | #include "llvm/DebugInfo/DWARF/DWARFFormValue.h" | 
|  | #include "llvm/DebugInfo/DWARF/DWARFSection.h" | 
|  | #include "llvm/Support/DJB.h" | 
|  | #include "llvm/Support/FormatVariadic.h" | 
|  | #include "llvm/Support/WithColor.h" | 
|  | #include "llvm/Support/raw_ostream.h" | 
|  | #include <map> | 
|  | #include <set> | 
|  | #include <vector> | 
|  |  | 
|  | using namespace llvm; | 
|  | using namespace dwarf; | 
|  | using namespace object; | 
|  |  | 
|  | DWARFVerifier::DieRangeInfo::address_range_iterator | 
|  | DWARFVerifier::DieRangeInfo::insert(const DWARFAddressRange &R) { | 
|  | auto Begin = Ranges.begin(); | 
|  | auto End = Ranges.end(); | 
|  | auto Pos = std::lower_bound(Begin, End, R); | 
|  |  | 
|  | if (Pos != End) { | 
|  | if (Pos->intersects(R)) | 
|  | return Pos; | 
|  | if (Pos != Begin) { | 
|  | auto Iter = Pos - 1; | 
|  | if (Iter->intersects(R)) | 
|  | return Iter; | 
|  | } | 
|  | } | 
|  |  | 
|  | Ranges.insert(Pos, R); | 
|  | return Ranges.end(); | 
|  | } | 
|  |  | 
|  | DWARFVerifier::DieRangeInfo::die_range_info_iterator | 
|  | DWARFVerifier::DieRangeInfo::insert(const DieRangeInfo &RI) { | 
|  | auto End = Children.end(); | 
|  | auto Iter = Children.begin(); | 
|  | while (Iter != End) { | 
|  | if (Iter->intersects(RI)) | 
|  | return Iter; | 
|  | ++Iter; | 
|  | } | 
|  | Children.insert(RI); | 
|  | return Children.end(); | 
|  | } | 
|  |  | 
|  | bool DWARFVerifier::DieRangeInfo::contains(const DieRangeInfo &RHS) const { | 
|  | // Both list of ranges are sorted so we can make this fast. | 
|  |  | 
|  | if (Ranges.empty() || RHS.Ranges.empty()) | 
|  | return false; | 
|  |  | 
|  | // Since the ranges are sorted we can advance where we start searching with | 
|  | // this object's ranges as we traverse RHS.Ranges. | 
|  | auto End = Ranges.end(); | 
|  | auto Iter = findRange(RHS.Ranges.front()); | 
|  |  | 
|  | // Now linearly walk the ranges in this object and see if they contain each | 
|  | // ranges from RHS.Ranges. | 
|  | for (const auto &R : RHS.Ranges) { | 
|  | while (Iter != End) { | 
|  | if (Iter->contains(R)) | 
|  | break; | 
|  | ++Iter; | 
|  | } | 
|  | if (Iter == End) | 
|  | return false; | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool DWARFVerifier::DieRangeInfo::intersects(const DieRangeInfo &RHS) const { | 
|  | if (Ranges.empty() || RHS.Ranges.empty()) | 
|  | return false; | 
|  |  | 
|  | auto End = Ranges.end(); | 
|  | auto Iter = findRange(RHS.Ranges.front()); | 
|  | for (const auto &R : RHS.Ranges) { | 
|  | if(Iter == End) | 
|  | return false; | 
|  | if (R.HighPC <= Iter->LowPC) | 
|  | continue; | 
|  | while (Iter != End) { | 
|  | if (Iter->intersects(R)) | 
|  | return true; | 
|  | ++Iter; | 
|  | } | 
|  | } | 
|  |  | 
|  | return false; | 
|  | } | 
|  |  | 
|  | bool DWARFVerifier::verifyUnitHeader(const DWARFDataExtractor DebugInfoData, | 
|  | uint32_t *Offset, unsigned UnitIndex, | 
|  | uint8_t &UnitType, bool &isUnitDWARF64) { | 
|  | uint32_t AbbrOffset, Length; | 
|  | uint8_t AddrSize = 0; | 
|  | uint16_t Version; | 
|  | bool Success = true; | 
|  |  | 
|  | bool ValidLength = false; | 
|  | bool ValidVersion = false; | 
|  | bool ValidAddrSize = false; | 
|  | bool ValidType = true; | 
|  | bool ValidAbbrevOffset = true; | 
|  |  | 
|  | uint32_t OffsetStart = *Offset; | 
|  | Length = DebugInfoData.getU32(Offset); | 
|  | if (Length == UINT32_MAX) { | 
|  | isUnitDWARF64 = true; | 
|  | OS << format( | 
|  | "Unit[%d] is in 64-bit DWARF format; cannot verify from this point.\n", | 
|  | UnitIndex); | 
|  | return false; | 
|  | } | 
|  | Version = DebugInfoData.getU16(Offset); | 
|  |  | 
|  | if (Version >= 5) { | 
|  | UnitType = DebugInfoData.getU8(Offset); | 
|  | AddrSize = DebugInfoData.getU8(Offset); | 
|  | AbbrOffset = DebugInfoData.getU32(Offset); | 
|  | ValidType = dwarf::isUnitType(UnitType); | 
|  | } else { | 
|  | UnitType = 0; | 
|  | AbbrOffset = DebugInfoData.getU32(Offset); | 
|  | AddrSize = DebugInfoData.getU8(Offset); | 
|  | } | 
|  |  | 
|  | if (!DCtx.getDebugAbbrev()->getAbbreviationDeclarationSet(AbbrOffset)) | 
|  | ValidAbbrevOffset = false; | 
|  |  | 
|  | ValidLength = DebugInfoData.isValidOffset(OffsetStart + Length + 3); | 
|  | ValidVersion = DWARFContext::isSupportedVersion(Version); | 
|  | ValidAddrSize = AddrSize == 4 || AddrSize == 8; | 
|  | if (!ValidLength || !ValidVersion || !ValidAddrSize || !ValidAbbrevOffset || | 
|  | !ValidType) { | 
|  | Success = false; | 
|  | error() << format("Units[%d] - start offset: 0x%08x \n", UnitIndex, | 
|  | OffsetStart); | 
|  | if (!ValidLength) | 
|  | note() << "The length for this unit is too " | 
|  | "large for the .debug_info provided.\n"; | 
|  | if (!ValidVersion) | 
|  | note() << "The 16 bit unit header version is not valid.\n"; | 
|  | if (!ValidType) | 
|  | note() << "The unit type encoding is not valid.\n"; | 
|  | if (!ValidAbbrevOffset) | 
|  | note() << "The offset into the .debug_abbrev section is " | 
|  | "not valid.\n"; | 
|  | if (!ValidAddrSize) | 
|  | note() << "The address size is unsupported.\n"; | 
|  | } | 
|  | *Offset = OffsetStart + Length + 4; | 
|  | return Success; | 
|  | } | 
|  |  | 
|  | bool DWARFVerifier::verifyUnitContents(DWARFUnit &Unit, uint8_t UnitType) { | 
|  | uint32_t NumUnitErrors = 0; | 
|  | unsigned NumDies = Unit.getNumDIEs(); | 
|  | for (unsigned I = 0; I < NumDies; ++I) { | 
|  | auto Die = Unit.getDIEAtIndex(I); | 
|  | if (Die.getTag() == DW_TAG_null) | 
|  | continue; | 
|  | for (auto AttrValue : Die.attributes()) { | 
|  | NumUnitErrors += verifyDebugInfoAttribute(Die, AttrValue); | 
|  | NumUnitErrors += verifyDebugInfoForm(Die, AttrValue); | 
|  | } | 
|  | } | 
|  |  | 
|  | DWARFDie Die = Unit.getUnitDIE(/* ExtractUnitDIEOnly = */ false); | 
|  | if (!Die) { | 
|  | error() << "Compilation unit without DIE.\n"; | 
|  | NumUnitErrors++; | 
|  | return NumUnitErrors == 0; | 
|  | } | 
|  |  | 
|  | if (!dwarf::isUnitType(Die.getTag())) { | 
|  | error() << "Compilation unit root DIE is not a unit DIE: " | 
|  | << dwarf::TagString(Die.getTag()) << ".\n"; | 
|  | NumUnitErrors++; | 
|  | } | 
|  |  | 
|  | if (UnitType != 0 && | 
|  | !DWARFUnit::isMatchingUnitTypeAndTag(UnitType, Die.getTag())) { | 
|  | error() << "Compilation unit type (" << dwarf::UnitTypeString(UnitType) | 
|  | << ") and root DIE (" << dwarf::TagString(Die.getTag()) | 
|  | << ") do not match.\n"; | 
|  | NumUnitErrors++; | 
|  | } | 
|  |  | 
|  | DieRangeInfo RI; | 
|  | NumUnitErrors += verifyDieRanges(Die, RI); | 
|  |  | 
|  | return NumUnitErrors == 0; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyAbbrevSection(const DWARFDebugAbbrev *Abbrev) { | 
|  | unsigned NumErrors = 0; | 
|  | if (Abbrev) { | 
|  | const DWARFAbbreviationDeclarationSet *AbbrDecls = | 
|  | Abbrev->getAbbreviationDeclarationSet(0); | 
|  | for (auto AbbrDecl : *AbbrDecls) { | 
|  | SmallDenseSet<uint16_t> AttributeSet; | 
|  | for (auto Attribute : AbbrDecl.attributes()) { | 
|  | auto Result = AttributeSet.insert(Attribute.Attr); | 
|  | if (!Result.second) { | 
|  | error() << "Abbreviation declaration contains multiple " | 
|  | << AttributeString(Attribute.Attr) << " attributes.\n"; | 
|  | AbbrDecl.dump(OS); | 
|  | ++NumErrors; | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | bool DWARFVerifier::handleDebugAbbrev() { | 
|  | OS << "Verifying .debug_abbrev...\n"; | 
|  |  | 
|  | const DWARFObject &DObj = DCtx.getDWARFObj(); | 
|  | bool noDebugAbbrev = DObj.getAbbrevSection().empty(); | 
|  | bool noDebugAbbrevDWO = DObj.getAbbrevDWOSection().empty(); | 
|  |  | 
|  | if (noDebugAbbrev && noDebugAbbrevDWO) { | 
|  | return true; | 
|  | } | 
|  |  | 
|  | unsigned NumErrors = 0; | 
|  | if (!noDebugAbbrev) | 
|  | NumErrors += verifyAbbrevSection(DCtx.getDebugAbbrev()); | 
|  |  | 
|  | if (!noDebugAbbrevDWO) | 
|  | NumErrors += verifyAbbrevSection(DCtx.getDebugAbbrevDWO()); | 
|  | return NumErrors == 0; | 
|  | } | 
|  |  | 
|  | bool DWARFVerifier::handleDebugInfo() { | 
|  | OS << "Verifying .debug_info Unit Header Chain...\n"; | 
|  |  | 
|  | const DWARFObject &DObj = DCtx.getDWARFObj(); | 
|  | DWARFDataExtractor DebugInfoData(DObj, DObj.getInfoSection(), | 
|  | DCtx.isLittleEndian(), 0); | 
|  | uint32_t NumDebugInfoErrors = 0; | 
|  | uint32_t OffsetStart = 0, Offset = 0, UnitIdx = 0; | 
|  | uint8_t UnitType = 0; | 
|  | bool isUnitDWARF64 = false; | 
|  | bool isHeaderChainValid = true; | 
|  | bool hasDIE = DebugInfoData.isValidOffset(Offset); | 
|  | DWARFUnitVector UnitVector{}; | 
|  | while (hasDIE) { | 
|  | OffsetStart = Offset; | 
|  | if (!verifyUnitHeader(DebugInfoData, &Offset, UnitIdx, UnitType, | 
|  | isUnitDWARF64)) { | 
|  | isHeaderChainValid = false; | 
|  | if (isUnitDWARF64) | 
|  | break; | 
|  | } else { | 
|  | DWARFUnitHeader Header; | 
|  | Header.extract(DCtx, DebugInfoData, &OffsetStart); | 
|  | std::unique_ptr<DWARFUnit> Unit; | 
|  | switch (UnitType) { | 
|  | case dwarf::DW_UT_type: | 
|  | case dwarf::DW_UT_split_type: { | 
|  | Unit.reset(new DWARFTypeUnit( | 
|  | DCtx, DObj.getInfoSection(), Header, DCtx.getDebugAbbrev(), | 
|  | &DObj.getRangeSection(), DObj.getStringSection(), | 
|  | DObj.getStringOffsetSection(), &DObj.getAppleObjCSection(), | 
|  | DObj.getLineSection(), DCtx.isLittleEndian(), false, UnitVector)); | 
|  | break; | 
|  | } | 
|  | case dwarf::DW_UT_skeleton: | 
|  | case dwarf::DW_UT_split_compile: | 
|  | case dwarf::DW_UT_compile: | 
|  | case dwarf::DW_UT_partial: | 
|  | // UnitType = 0 means that we are | 
|  | // verifying a compile unit in DWARF v4. | 
|  | case 0: { | 
|  | Unit.reset(new DWARFCompileUnit( | 
|  | DCtx, DObj.getInfoSection(), Header, DCtx.getDebugAbbrev(), | 
|  | &DObj.getRangeSection(), DObj.getStringSection(), | 
|  | DObj.getStringOffsetSection(), &DObj.getAppleObjCSection(), | 
|  | DObj.getLineSection(), DCtx.isLittleEndian(), false, UnitVector)); | 
|  | break; | 
|  | } | 
|  | default: { llvm_unreachable("Invalid UnitType."); } | 
|  | } | 
|  | if (!verifyUnitContents(*Unit, UnitType)) | 
|  | ++NumDebugInfoErrors; | 
|  | } | 
|  | hasDIE = DebugInfoData.isValidOffset(Offset); | 
|  | ++UnitIdx; | 
|  | } | 
|  | if (UnitIdx == 0 && !hasDIE) { | 
|  | warn() << ".debug_info is empty.\n"; | 
|  | isHeaderChainValid = true; | 
|  | } | 
|  | NumDebugInfoErrors += verifyDebugInfoReferences(); | 
|  | return (isHeaderChainValid && NumDebugInfoErrors == 0); | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyDieRanges(const DWARFDie &Die, | 
|  | DieRangeInfo &ParentRI) { | 
|  | unsigned NumErrors = 0; | 
|  |  | 
|  | if (!Die.isValid()) | 
|  | return NumErrors; | 
|  |  | 
|  | auto RangesOrError = Die.getAddressRanges(); | 
|  | if (!RangesOrError) { | 
|  | // FIXME: Report the error. | 
|  | ++NumErrors; | 
|  | llvm::consumeError(RangesOrError.takeError()); | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | DWARFAddressRangesVector Ranges = RangesOrError.get(); | 
|  | // Build RI for this DIE and check that ranges within this DIE do not | 
|  | // overlap. | 
|  | DieRangeInfo RI(Die); | 
|  | for (auto Range : Ranges) { | 
|  | if (!Range.valid()) { | 
|  | ++NumErrors; | 
|  | error() << "Invalid address range " << Range << "\n"; | 
|  | continue; | 
|  | } | 
|  |  | 
|  | // Verify that ranges don't intersect. | 
|  | const auto IntersectingRange = RI.insert(Range); | 
|  | if (IntersectingRange != RI.Ranges.end()) { | 
|  | ++NumErrors; | 
|  | error() << "DIE has overlapping address ranges: " << Range << " and " | 
|  | << *IntersectingRange << "\n"; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | // Verify that children don't intersect. | 
|  | const auto IntersectingChild = ParentRI.insert(RI); | 
|  | if (IntersectingChild != ParentRI.Children.end()) { | 
|  | ++NumErrors; | 
|  | error() << "DIEs have overlapping address ranges:"; | 
|  | Die.dump(OS, 0); | 
|  | IntersectingChild->Die.dump(OS, 0); | 
|  | OS << "\n"; | 
|  | } | 
|  |  | 
|  | // Verify that ranges are contained within their parent. | 
|  | bool ShouldBeContained = !Ranges.empty() && !ParentRI.Ranges.empty() && | 
|  | !(Die.getTag() == DW_TAG_subprogram && | 
|  | ParentRI.Die.getTag() == DW_TAG_subprogram); | 
|  | if (ShouldBeContained && !ParentRI.contains(RI)) { | 
|  | ++NumErrors; | 
|  | error() << "DIE address ranges are not contained in its parent's ranges:"; | 
|  | ParentRI.Die.dump(OS, 0); | 
|  | Die.dump(OS, 2); | 
|  | OS << "\n"; | 
|  | } | 
|  |  | 
|  | // Recursively check children. | 
|  | for (DWARFDie Child : Die) | 
|  | NumErrors += verifyDieRanges(Child, RI); | 
|  |  | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyDebugInfoAttribute(const DWARFDie &Die, | 
|  | DWARFAttribute &AttrValue) { | 
|  | unsigned NumErrors = 0; | 
|  | auto ReportError = [&](const Twine &TitleMsg) { | 
|  | ++NumErrors; | 
|  | error() << TitleMsg << '\n'; | 
|  | Die.dump(OS, 0, DumpOpts); | 
|  | OS << "\n"; | 
|  | }; | 
|  |  | 
|  | const DWARFObject &DObj = DCtx.getDWARFObj(); | 
|  | const auto Attr = AttrValue.Attr; | 
|  | switch (Attr) { | 
|  | case DW_AT_ranges: | 
|  | // Make sure the offset in the DW_AT_ranges attribute is valid. | 
|  | if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) { | 
|  | if (*SectionOffset >= DObj.getRangeSection().Data.size()) | 
|  | ReportError("DW_AT_ranges offset is beyond .debug_ranges bounds:"); | 
|  | break; | 
|  | } | 
|  | ReportError("DIE has invalid DW_AT_ranges encoding:"); | 
|  | break; | 
|  | case DW_AT_stmt_list: | 
|  | // Make sure the offset in the DW_AT_stmt_list attribute is valid. | 
|  | if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) { | 
|  | if (*SectionOffset >= DObj.getLineSection().Data.size()) | 
|  | ReportError("DW_AT_stmt_list offset is beyond .debug_line bounds: " + | 
|  | llvm::formatv("{0:x8}", *SectionOffset)); | 
|  | break; | 
|  | } | 
|  | ReportError("DIE has invalid DW_AT_stmt_list encoding:"); | 
|  | break; | 
|  | case DW_AT_location: { | 
|  | auto VerifyLocationExpr = [&](StringRef D) { | 
|  | DWARFUnit *U = Die.getDwarfUnit(); | 
|  | DataExtractor Data(D, DCtx.isLittleEndian(), 0); | 
|  | DWARFExpression Expression(Data, U->getVersion(), | 
|  | U->getAddressByteSize()); | 
|  | bool Error = llvm::any_of(Expression, [](DWARFExpression::Operation &Op) { | 
|  | return Op.isError(); | 
|  | }); | 
|  | if (Error) | 
|  | ReportError("DIE contains invalid DWARF expression:"); | 
|  | }; | 
|  | if (Optional<ArrayRef<uint8_t>> Expr = AttrValue.Value.getAsBlock()) { | 
|  | // Verify inlined location. | 
|  | VerifyLocationExpr(llvm::toStringRef(*Expr)); | 
|  | } else if (auto LocOffset = AttrValue.Value.getAsSectionOffset()) { | 
|  | // Verify location list. | 
|  | if (auto DebugLoc = DCtx.getDebugLoc()) | 
|  | if (auto LocList = DebugLoc->getLocationListAtOffset(*LocOffset)) | 
|  | for (const auto &Entry : LocList->Entries) | 
|  | VerifyLocationExpr({Entry.Loc.data(), Entry.Loc.size()}); | 
|  | } | 
|  | break; | 
|  | } | 
|  |  | 
|  | default: | 
|  | break; | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyDebugInfoForm(const DWARFDie &Die, | 
|  | DWARFAttribute &AttrValue) { | 
|  | const DWARFObject &DObj = DCtx.getDWARFObj(); | 
|  | unsigned NumErrors = 0; | 
|  | const auto Form = AttrValue.Value.getForm(); | 
|  | switch (Form) { | 
|  | case DW_FORM_ref1: | 
|  | case DW_FORM_ref2: | 
|  | case DW_FORM_ref4: | 
|  | case DW_FORM_ref8: | 
|  | case DW_FORM_ref_udata: { | 
|  | // Verify all CU relative references are valid CU offsets. | 
|  | Optional<uint64_t> RefVal = AttrValue.Value.getAsReference(); | 
|  | assert(RefVal); | 
|  | if (RefVal) { | 
|  | auto DieCU = Die.getDwarfUnit(); | 
|  | auto CUSize = DieCU->getNextUnitOffset() - DieCU->getOffset(); | 
|  | auto CUOffset = AttrValue.Value.getRawUValue(); | 
|  | if (CUOffset >= CUSize) { | 
|  | ++NumErrors; | 
|  | error() << FormEncodingString(Form) << " CU offset " | 
|  | << format("0x%08" PRIx64, CUOffset) | 
|  | << " is invalid (must be less than CU size of " | 
|  | << format("0x%08" PRIx32, CUSize) << "):\n"; | 
|  | Die.dump(OS, 0, DumpOpts); | 
|  | OS << "\n"; | 
|  | } else { | 
|  | // Valid reference, but we will verify it points to an actual | 
|  | // DIE later. | 
|  | ReferenceToDIEOffsets[*RefVal].insert(Die.getOffset()); | 
|  | } | 
|  | } | 
|  | break; | 
|  | } | 
|  | case DW_FORM_ref_addr: { | 
|  | // Verify all absolute DIE references have valid offsets in the | 
|  | // .debug_info section. | 
|  | Optional<uint64_t> RefVal = AttrValue.Value.getAsReference(); | 
|  | assert(RefVal); | 
|  | if (RefVal) { | 
|  | if (*RefVal >= DObj.getInfoSection().Data.size()) { | 
|  | ++NumErrors; | 
|  | error() << "DW_FORM_ref_addr offset beyond .debug_info " | 
|  | "bounds:\n"; | 
|  | Die.dump(OS, 0, DumpOpts); | 
|  | OS << "\n"; | 
|  | } else { | 
|  | // Valid reference, but we will verify it points to an actual | 
|  | // DIE later. | 
|  | ReferenceToDIEOffsets[*RefVal].insert(Die.getOffset()); | 
|  | } | 
|  | } | 
|  | break; | 
|  | } | 
|  | case DW_FORM_strp: { | 
|  | auto SecOffset = AttrValue.Value.getAsSectionOffset(); | 
|  | assert(SecOffset); // DW_FORM_strp is a section offset. | 
|  | if (SecOffset && *SecOffset >= DObj.getStringSection().size()) { | 
|  | ++NumErrors; | 
|  | error() << "DW_FORM_strp offset beyond .debug_str bounds:\n"; | 
|  | Die.dump(OS, 0, DumpOpts); | 
|  | OS << "\n"; | 
|  | } | 
|  | break; | 
|  | } | 
|  | default: | 
|  | break; | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyDebugInfoReferences() { | 
|  | // Take all references and make sure they point to an actual DIE by | 
|  | // getting the DIE by offset and emitting an error | 
|  | OS << "Verifying .debug_info references...\n"; | 
|  | unsigned NumErrors = 0; | 
|  | for (auto Pair : ReferenceToDIEOffsets) { | 
|  | auto Die = DCtx.getDIEForOffset(Pair.first); | 
|  | if (Die) | 
|  | continue; | 
|  | ++NumErrors; | 
|  | error() << "invalid DIE reference " << format("0x%08" PRIx64, Pair.first) | 
|  | << ". Offset is in between DIEs:\n"; | 
|  | for (auto Offset : Pair.second) { | 
|  | auto ReferencingDie = DCtx.getDIEForOffset(Offset); | 
|  | ReferencingDie.dump(OS, 0, DumpOpts); | 
|  | OS << "\n"; | 
|  | } | 
|  | OS << "\n"; | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | void DWARFVerifier::verifyDebugLineStmtOffsets() { | 
|  | std::map<uint64_t, DWARFDie> StmtListToDie; | 
|  | for (const auto &CU : DCtx.compile_units()) { | 
|  | auto Die = CU->getUnitDIE(); | 
|  | // Get the attribute value as a section offset. No need to produce an | 
|  | // error here if the encoding isn't correct because we validate this in | 
|  | // the .debug_info verifier. | 
|  | auto StmtSectionOffset = toSectionOffset(Die.find(DW_AT_stmt_list)); | 
|  | if (!StmtSectionOffset) | 
|  | continue; | 
|  | const uint32_t LineTableOffset = *StmtSectionOffset; | 
|  | auto LineTable = DCtx.getLineTableForUnit(CU.get()); | 
|  | if (LineTableOffset < DCtx.getDWARFObj().getLineSection().Data.size()) { | 
|  | if (!LineTable) { | 
|  | ++NumDebugLineErrors; | 
|  | error() << ".debug_line[" << format("0x%08" PRIx32, LineTableOffset) | 
|  | << "] was not able to be parsed for CU:\n"; | 
|  | Die.dump(OS, 0, DumpOpts); | 
|  | OS << '\n'; | 
|  | continue; | 
|  | } | 
|  | } else { | 
|  | // Make sure we don't get a valid line table back if the offset is wrong. | 
|  | assert(LineTable == nullptr); | 
|  | // Skip this line table as it isn't valid. No need to create an error | 
|  | // here because we validate this in the .debug_info verifier. | 
|  | continue; | 
|  | } | 
|  | auto Iter = StmtListToDie.find(LineTableOffset); | 
|  | if (Iter != StmtListToDie.end()) { | 
|  | ++NumDebugLineErrors; | 
|  | error() << "two compile unit DIEs, " | 
|  | << format("0x%08" PRIx32, Iter->second.getOffset()) << " and " | 
|  | << format("0x%08" PRIx32, Die.getOffset()) | 
|  | << ", have the same DW_AT_stmt_list section offset:\n"; | 
|  | Iter->second.dump(OS, 0, DumpOpts); | 
|  | Die.dump(OS, 0, DumpOpts); | 
|  | OS << '\n'; | 
|  | // Already verified this line table before, no need to do it again. | 
|  | continue; | 
|  | } | 
|  | StmtListToDie[LineTableOffset] = Die; | 
|  | } | 
|  | } | 
|  |  | 
|  | void DWARFVerifier::verifyDebugLineRows() { | 
|  | for (const auto &CU : DCtx.compile_units()) { | 
|  | auto Die = CU->getUnitDIE(); | 
|  | auto LineTable = DCtx.getLineTableForUnit(CU.get()); | 
|  | // If there is no line table we will have created an error in the | 
|  | // .debug_info verifier or in verifyDebugLineStmtOffsets(). | 
|  | if (!LineTable) | 
|  | continue; | 
|  |  | 
|  | // Verify prologue. | 
|  | uint32_t MaxFileIndex = LineTable->Prologue.FileNames.size(); | 
|  | uint32_t MaxDirIndex = LineTable->Prologue.IncludeDirectories.size(); | 
|  | uint32_t FileIndex = 1; | 
|  | StringMap<uint16_t> FullPathMap; | 
|  | for (const auto &FileName : LineTable->Prologue.FileNames) { | 
|  | // Verify directory index. | 
|  | if (FileName.DirIdx > MaxDirIndex) { | 
|  | ++NumDebugLineErrors; | 
|  | error() << ".debug_line[" | 
|  | << format("0x%08" PRIx64, | 
|  | *toSectionOffset(Die.find(DW_AT_stmt_list))) | 
|  | << "].prologue.file_names[" << FileIndex | 
|  | << "].dir_idx contains an invalid index: " << FileName.DirIdx | 
|  | << "\n"; | 
|  | } | 
|  |  | 
|  | // Check file paths for duplicates. | 
|  | std::string FullPath; | 
|  | const bool HasFullPath = LineTable->getFileNameByIndex( | 
|  | FileIndex, CU->getCompilationDir(), | 
|  | DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, FullPath); | 
|  | assert(HasFullPath && "Invalid index?"); | 
|  | (void)HasFullPath; | 
|  | auto It = FullPathMap.find(FullPath); | 
|  | if (It == FullPathMap.end()) | 
|  | FullPathMap[FullPath] = FileIndex; | 
|  | else if (It->second != FileIndex) { | 
|  | warn() << ".debug_line[" | 
|  | << format("0x%08" PRIx64, | 
|  | *toSectionOffset(Die.find(DW_AT_stmt_list))) | 
|  | << "].prologue.file_names[" << FileIndex | 
|  | << "] is a duplicate of file_names[" << It->second << "]\n"; | 
|  | } | 
|  |  | 
|  | FileIndex++; | 
|  | } | 
|  |  | 
|  | // Verify rows. | 
|  | uint64_t PrevAddress = 0; | 
|  | uint32_t RowIndex = 0; | 
|  | for (const auto &Row : LineTable->Rows) { | 
|  | // Verify row address. | 
|  | if (Row.Address < PrevAddress) { | 
|  | ++NumDebugLineErrors; | 
|  | error() << ".debug_line[" | 
|  | << format("0x%08" PRIx64, | 
|  | *toSectionOffset(Die.find(DW_AT_stmt_list))) | 
|  | << "] row[" << RowIndex | 
|  | << "] decreases in address from previous row:\n"; | 
|  |  | 
|  | DWARFDebugLine::Row::dumpTableHeader(OS); | 
|  | if (RowIndex > 0) | 
|  | LineTable->Rows[RowIndex - 1].dump(OS); | 
|  | Row.dump(OS); | 
|  | OS << '\n'; | 
|  | } | 
|  |  | 
|  | // Verify file index. | 
|  | if (Row.File > MaxFileIndex) { | 
|  | ++NumDebugLineErrors; | 
|  | error() << ".debug_line[" | 
|  | << format("0x%08" PRIx64, | 
|  | *toSectionOffset(Die.find(DW_AT_stmt_list))) | 
|  | << "][" << RowIndex << "] has invalid file index " << Row.File | 
|  | << " (valid values are [1," << MaxFileIndex << "]):\n"; | 
|  | DWARFDebugLine::Row::dumpTableHeader(OS); | 
|  | Row.dump(OS); | 
|  | OS << '\n'; | 
|  | } | 
|  | if (Row.EndSequence) | 
|  | PrevAddress = 0; | 
|  | else | 
|  | PrevAddress = Row.Address; | 
|  | ++RowIndex; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | bool DWARFVerifier::handleDebugLine() { | 
|  | NumDebugLineErrors = 0; | 
|  | OS << "Verifying .debug_line...\n"; | 
|  | verifyDebugLineStmtOffsets(); | 
|  | verifyDebugLineRows(); | 
|  | return NumDebugLineErrors == 0; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyAppleAccelTable(const DWARFSection *AccelSection, | 
|  | DataExtractor *StrData, | 
|  | const char *SectionName) { | 
|  | unsigned NumErrors = 0; | 
|  | DWARFDataExtractor AccelSectionData(DCtx.getDWARFObj(), *AccelSection, | 
|  | DCtx.isLittleEndian(), 0); | 
|  | AppleAcceleratorTable AccelTable(AccelSectionData, *StrData); | 
|  |  | 
|  | OS << "Verifying " << SectionName << "...\n"; | 
|  |  | 
|  | // Verify that the fixed part of the header is not too short. | 
|  | if (!AccelSectionData.isValidOffset(AccelTable.getSizeHdr())) { | 
|  | error() << "Section is too small to fit a section header.\n"; | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | // Verify that the section is not too short. | 
|  | if (Error E = AccelTable.extract()) { | 
|  | error() << toString(std::move(E)) << '\n'; | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | // Verify that all buckets have a valid hash index or are empty. | 
|  | uint32_t NumBuckets = AccelTable.getNumBuckets(); | 
|  | uint32_t NumHashes = AccelTable.getNumHashes(); | 
|  |  | 
|  | uint32_t BucketsOffset = | 
|  | AccelTable.getSizeHdr() + AccelTable.getHeaderDataLength(); | 
|  | uint32_t HashesBase = BucketsOffset + NumBuckets * 4; | 
|  | uint32_t OffsetsBase = HashesBase + NumHashes * 4; | 
|  | for (uint32_t BucketIdx = 0; BucketIdx < NumBuckets; ++BucketIdx) { | 
|  | uint32_t HashIdx = AccelSectionData.getU32(&BucketsOffset); | 
|  | if (HashIdx >= NumHashes && HashIdx != UINT32_MAX) { | 
|  | error() << format("Bucket[%d] has invalid hash index: %u.\n", BucketIdx, | 
|  | HashIdx); | 
|  | ++NumErrors; | 
|  | } | 
|  | } | 
|  | uint32_t NumAtoms = AccelTable.getAtomsDesc().size(); | 
|  | if (NumAtoms == 0) { | 
|  | error() << "No atoms: failed to read HashData.\n"; | 
|  | return 1; | 
|  | } | 
|  | if (!AccelTable.validateForms()) { | 
|  | error() << "Unsupported form: failed to read HashData.\n"; | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | for (uint32_t HashIdx = 0; HashIdx < NumHashes; ++HashIdx) { | 
|  | uint32_t HashOffset = HashesBase + 4 * HashIdx; | 
|  | uint32_t DataOffset = OffsetsBase + 4 * HashIdx; | 
|  | uint32_t Hash = AccelSectionData.getU32(&HashOffset); | 
|  | uint32_t HashDataOffset = AccelSectionData.getU32(&DataOffset); | 
|  | if (!AccelSectionData.isValidOffsetForDataOfSize(HashDataOffset, | 
|  | sizeof(uint64_t))) { | 
|  | error() << format("Hash[%d] has invalid HashData offset: 0x%08x.\n", | 
|  | HashIdx, HashDataOffset); | 
|  | ++NumErrors; | 
|  | } | 
|  |  | 
|  | uint32_t StrpOffset; | 
|  | uint32_t StringOffset; | 
|  | uint32_t StringCount = 0; | 
|  | unsigned Offset; | 
|  | unsigned Tag; | 
|  | while ((StrpOffset = AccelSectionData.getU32(&HashDataOffset)) != 0) { | 
|  | const uint32_t NumHashDataObjects = | 
|  | AccelSectionData.getU32(&HashDataOffset); | 
|  | for (uint32_t HashDataIdx = 0; HashDataIdx < NumHashDataObjects; | 
|  | ++HashDataIdx) { | 
|  | std::tie(Offset, Tag) = AccelTable.readAtoms(HashDataOffset); | 
|  | auto Die = DCtx.getDIEForOffset(Offset); | 
|  | if (!Die) { | 
|  | const uint32_t BucketIdx = | 
|  | NumBuckets ? (Hash % NumBuckets) : UINT32_MAX; | 
|  | StringOffset = StrpOffset; | 
|  | const char *Name = StrData->getCStr(&StringOffset); | 
|  | if (!Name) | 
|  | Name = "<NULL>"; | 
|  |  | 
|  | error() << format( | 
|  | "%s Bucket[%d] Hash[%d] = 0x%08x " | 
|  | "Str[%u] = 0x%08x " | 
|  | "DIE[%d] = 0x%08x is not a valid DIE offset for \"%s\".\n", | 
|  | SectionName, BucketIdx, HashIdx, Hash, StringCount, StrpOffset, | 
|  | HashDataIdx, Offset, Name); | 
|  |  | 
|  | ++NumErrors; | 
|  | continue; | 
|  | } | 
|  | if ((Tag != dwarf::DW_TAG_null) && (Die.getTag() != Tag)) { | 
|  | error() << "Tag " << dwarf::TagString(Tag) | 
|  | << " in accelerator table does not match Tag " | 
|  | << dwarf::TagString(Die.getTag()) << " of DIE[" << HashDataIdx | 
|  | << "].\n"; | 
|  | ++NumErrors; | 
|  | } | 
|  | } | 
|  | ++StringCount; | 
|  | } | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | unsigned | 
|  | DWARFVerifier::verifyDebugNamesCULists(const DWARFDebugNames &AccelTable) { | 
|  | // A map from CU offset to the (first) Name Index offset which claims to index | 
|  | // this CU. | 
|  | DenseMap<uint32_t, uint32_t> CUMap; | 
|  | const uint32_t NotIndexed = std::numeric_limits<uint32_t>::max(); | 
|  |  | 
|  | CUMap.reserve(DCtx.getNumCompileUnits()); | 
|  | for (const auto &CU : DCtx.compile_units()) | 
|  | CUMap[CU->getOffset()] = NotIndexed; | 
|  |  | 
|  | unsigned NumErrors = 0; | 
|  | for (const DWARFDebugNames::NameIndex &NI : AccelTable) { | 
|  | if (NI.getCUCount() == 0) { | 
|  | error() << formatv("Name Index @ {0:x} does not index any CU\n", | 
|  | NI.getUnitOffset()); | 
|  | ++NumErrors; | 
|  | continue; | 
|  | } | 
|  | for (uint32_t CU = 0, End = NI.getCUCount(); CU < End; ++CU) { | 
|  | uint32_t Offset = NI.getCUOffset(CU); | 
|  | auto Iter = CUMap.find(Offset); | 
|  |  | 
|  | if (Iter == CUMap.end()) { | 
|  | error() << formatv( | 
|  | "Name Index @ {0:x} references a non-existing CU @ {1:x}\n", | 
|  | NI.getUnitOffset(), Offset); | 
|  | ++NumErrors; | 
|  | continue; | 
|  | } | 
|  |  | 
|  | if (Iter->second != NotIndexed) { | 
|  | error() << formatv("Name Index @ {0:x} references a CU @ {1:x}, but " | 
|  | "this CU is already indexed by Name Index @ {2:x}\n", | 
|  | NI.getUnitOffset(), Offset, Iter->second); | 
|  | continue; | 
|  | } | 
|  | Iter->second = NI.getUnitOffset(); | 
|  | } | 
|  | } | 
|  |  | 
|  | for (const auto &KV : CUMap) { | 
|  | if (KV.second == NotIndexed) | 
|  | warn() << formatv("CU @ {0:x} not covered by any Name Index\n", KV.first); | 
|  | } | 
|  |  | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | unsigned | 
|  | DWARFVerifier::verifyNameIndexBuckets(const DWARFDebugNames::NameIndex &NI, | 
|  | const DataExtractor &StrData) { | 
|  | struct BucketInfo { | 
|  | uint32_t Bucket; | 
|  | uint32_t Index; | 
|  |  | 
|  | constexpr BucketInfo(uint32_t Bucket, uint32_t Index) | 
|  | : Bucket(Bucket), Index(Index) {} | 
|  | bool operator<(const BucketInfo &RHS) const { return Index < RHS.Index; }; | 
|  | }; | 
|  |  | 
|  | uint32_t NumErrors = 0; | 
|  | if (NI.getBucketCount() == 0) { | 
|  | warn() << formatv("Name Index @ {0:x} does not contain a hash table.\n", | 
|  | NI.getUnitOffset()); | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | // Build up a list of (Bucket, Index) pairs. We use this later to verify that | 
|  | // each Name is reachable from the appropriate bucket. | 
|  | std::vector<BucketInfo> BucketStarts; | 
|  | BucketStarts.reserve(NI.getBucketCount() + 1); | 
|  | for (uint32_t Bucket = 0, End = NI.getBucketCount(); Bucket < End; ++Bucket) { | 
|  | uint32_t Index = NI.getBucketArrayEntry(Bucket); | 
|  | if (Index > NI.getNameCount()) { | 
|  | error() << formatv("Bucket {0} of Name Index @ {1:x} contains invalid " | 
|  | "value {2}. Valid range is [0, {3}].\n", | 
|  | Bucket, NI.getUnitOffset(), Index, NI.getNameCount()); | 
|  | ++NumErrors; | 
|  | continue; | 
|  | } | 
|  | if (Index > 0) | 
|  | BucketStarts.emplace_back(Bucket, Index); | 
|  | } | 
|  |  | 
|  | // If there were any buckets with invalid values, skip further checks as they | 
|  | // will likely produce many errors which will only confuse the actual root | 
|  | // problem. | 
|  | if (NumErrors > 0) | 
|  | return NumErrors; | 
|  |  | 
|  | // Sort the list in the order of increasing "Index" entries. | 
|  | array_pod_sort(BucketStarts.begin(), BucketStarts.end()); | 
|  |  | 
|  | // Insert a sentinel entry at the end, so we can check that the end of the | 
|  | // table is covered in the loop below. | 
|  | BucketStarts.emplace_back(NI.getBucketCount(), NI.getNameCount() + 1); | 
|  |  | 
|  | // Loop invariant: NextUncovered is the (1-based) index of the first Name | 
|  | // which is not reachable by any of the buckets we processed so far (and | 
|  | // hasn't been reported as uncovered). | 
|  | uint32_t NextUncovered = 1; | 
|  | for (const BucketInfo &B : BucketStarts) { | 
|  | // Under normal circumstances B.Index be equal to NextUncovered, but it can | 
|  | // be less if a bucket points to names which are already known to be in some | 
|  | // bucket we processed earlier. In that case, we won't trigger this error, | 
|  | // but report the mismatched hash value error instead. (We know the hash | 
|  | // will not match because we have already verified that the name's hash | 
|  | // puts it into the previous bucket.) | 
|  | if (B.Index > NextUncovered) { | 
|  | error() << formatv("Name Index @ {0:x}: Name table entries [{1}, {2}] " | 
|  | "are not covered by the hash table.\n", | 
|  | NI.getUnitOffset(), NextUncovered, B.Index - 1); | 
|  | ++NumErrors; | 
|  | } | 
|  | uint32_t Idx = B.Index; | 
|  |  | 
|  | // The rest of the checks apply only to non-sentinel entries. | 
|  | if (B.Bucket == NI.getBucketCount()) | 
|  | break; | 
|  |  | 
|  | // This triggers if a non-empty bucket points to a name with a mismatched | 
|  | // hash. Clients are likely to interpret this as an empty bucket, because a | 
|  | // mismatched hash signals the end of a bucket, but if this is indeed an | 
|  | // empty bucket, the producer should have signalled this by marking the | 
|  | // bucket as empty. | 
|  | uint32_t FirstHash = NI.getHashArrayEntry(Idx); | 
|  | if (FirstHash % NI.getBucketCount() != B.Bucket) { | 
|  | error() << formatv( | 
|  | "Name Index @ {0:x}: Bucket {1} is not empty but points to a " | 
|  | "mismatched hash value {2:x} (belonging to bucket {3}).\n", | 
|  | NI.getUnitOffset(), B.Bucket, FirstHash, | 
|  | FirstHash % NI.getBucketCount()); | 
|  | ++NumErrors; | 
|  | } | 
|  |  | 
|  | // This find the end of this bucket and also verifies that all the hashes in | 
|  | // this bucket are correct by comparing the stored hashes to the ones we | 
|  | // compute ourselves. | 
|  | while (Idx <= NI.getNameCount()) { | 
|  | uint32_t Hash = NI.getHashArrayEntry(Idx); | 
|  | if (Hash % NI.getBucketCount() != B.Bucket) | 
|  | break; | 
|  |  | 
|  | const char *Str = NI.getNameTableEntry(Idx).getString(); | 
|  | if (caseFoldingDjbHash(Str) != Hash) { | 
|  | error() << formatv("Name Index @ {0:x}: String ({1}) at index {2} " | 
|  | "hashes to {3:x}, but " | 
|  | "the Name Index hash is {4:x}\n", | 
|  | NI.getUnitOffset(), Str, Idx, | 
|  | caseFoldingDjbHash(Str), Hash); | 
|  | ++NumErrors; | 
|  | } | 
|  |  | 
|  | ++Idx; | 
|  | } | 
|  | NextUncovered = std::max(NextUncovered, Idx); | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyNameIndexAttribute( | 
|  | const DWARFDebugNames::NameIndex &NI, const DWARFDebugNames::Abbrev &Abbr, | 
|  | DWARFDebugNames::AttributeEncoding AttrEnc) { | 
|  | StringRef FormName = dwarf::FormEncodingString(AttrEnc.Form); | 
|  | if (FormName.empty()) { | 
|  | error() << formatv("NameIndex @ {0:x}: Abbreviation {1:x}: {2} uses an " | 
|  | "unknown form: {3}.\n", | 
|  | NI.getUnitOffset(), Abbr.Code, AttrEnc.Index, | 
|  | AttrEnc.Form); | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | if (AttrEnc.Index == DW_IDX_type_hash) { | 
|  | if (AttrEnc.Form != dwarf::DW_FORM_data8) { | 
|  | error() << formatv( | 
|  | "NameIndex @ {0:x}: Abbreviation {1:x}: DW_IDX_type_hash " | 
|  | "uses an unexpected form {2} (should be {3}).\n", | 
|  | NI.getUnitOffset(), Abbr.Code, AttrEnc.Form, dwarf::DW_FORM_data8); | 
|  | return 1; | 
|  | } | 
|  | } | 
|  |  | 
|  | // A list of known index attributes and their expected form classes. | 
|  | // DW_IDX_type_hash is handled specially in the check above, as it has a | 
|  | // specific form (not just a form class) we should expect. | 
|  | struct FormClassTable { | 
|  | dwarf::Index Index; | 
|  | DWARFFormValue::FormClass Class; | 
|  | StringLiteral ClassName; | 
|  | }; | 
|  | static constexpr FormClassTable Table[] = { | 
|  | {dwarf::DW_IDX_compile_unit, DWARFFormValue::FC_Constant, {"constant"}}, | 
|  | {dwarf::DW_IDX_type_unit, DWARFFormValue::FC_Constant, {"constant"}}, | 
|  | {dwarf::DW_IDX_die_offset, DWARFFormValue::FC_Reference, {"reference"}}, | 
|  | {dwarf::DW_IDX_parent, DWARFFormValue::FC_Constant, {"constant"}}, | 
|  | }; | 
|  |  | 
|  | ArrayRef<FormClassTable> TableRef(Table); | 
|  | auto Iter = find_if(TableRef, [AttrEnc](const FormClassTable &T) { | 
|  | return T.Index == AttrEnc.Index; | 
|  | }); | 
|  | if (Iter == TableRef.end()) { | 
|  | warn() << formatv("NameIndex @ {0:x}: Abbreviation {1:x} contains an " | 
|  | "unknown index attribute: {2}.\n", | 
|  | NI.getUnitOffset(), Abbr.Code, AttrEnc.Index); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (!DWARFFormValue(AttrEnc.Form).isFormClass(Iter->Class)) { | 
|  | error() << formatv("NameIndex @ {0:x}: Abbreviation {1:x}: {2} uses an " | 
|  | "unexpected form {3} (expected form class {4}).\n", | 
|  | NI.getUnitOffset(), Abbr.Code, AttrEnc.Index, | 
|  | AttrEnc.Form, Iter->ClassName); | 
|  | return 1; | 
|  | } | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | unsigned | 
|  | DWARFVerifier::verifyNameIndexAbbrevs(const DWARFDebugNames::NameIndex &NI) { | 
|  | if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0) { | 
|  | warn() << formatv("Name Index @ {0:x}: Verifying indexes of type units is " | 
|  | "not currently supported.\n", | 
|  | NI.getUnitOffset()); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | unsigned NumErrors = 0; | 
|  | for (const auto &Abbrev : NI.getAbbrevs()) { | 
|  | StringRef TagName = dwarf::TagString(Abbrev.Tag); | 
|  | if (TagName.empty()) { | 
|  | warn() << formatv("NameIndex @ {0:x}: Abbreviation {1:x} references an " | 
|  | "unknown tag: {2}.\n", | 
|  | NI.getUnitOffset(), Abbrev.Code, Abbrev.Tag); | 
|  | } | 
|  | SmallSet<unsigned, 5> Attributes; | 
|  | for (const auto &AttrEnc : Abbrev.Attributes) { | 
|  | if (!Attributes.insert(AttrEnc.Index).second) { | 
|  | error() << formatv("NameIndex @ {0:x}: Abbreviation {1:x} contains " | 
|  | "multiple {2} attributes.\n", | 
|  | NI.getUnitOffset(), Abbrev.Code, AttrEnc.Index); | 
|  | ++NumErrors; | 
|  | continue; | 
|  | } | 
|  | NumErrors += verifyNameIndexAttribute(NI, Abbrev, AttrEnc); | 
|  | } | 
|  |  | 
|  | if (NI.getCUCount() > 1 && !Attributes.count(dwarf::DW_IDX_compile_unit)) { | 
|  | error() << formatv("NameIndex @ {0:x}: Indexing multiple compile units " | 
|  | "and abbreviation {1:x} has no {2} attribute.\n", | 
|  | NI.getUnitOffset(), Abbrev.Code, | 
|  | dwarf::DW_IDX_compile_unit); | 
|  | ++NumErrors; | 
|  | } | 
|  | if (!Attributes.count(dwarf::DW_IDX_die_offset)) { | 
|  | error() << formatv( | 
|  | "NameIndex @ {0:x}: Abbreviation {1:x} has no {2} attribute.\n", | 
|  | NI.getUnitOffset(), Abbrev.Code, dwarf::DW_IDX_die_offset); | 
|  | ++NumErrors; | 
|  | } | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | static SmallVector<StringRef, 2> getNames(const DWARFDie &DIE) { | 
|  | SmallVector<StringRef, 2> Result; | 
|  | if (const char *Str = DIE.getName(DINameKind::ShortName)) | 
|  | Result.emplace_back(Str); | 
|  | else if (DIE.getTag() == dwarf::DW_TAG_namespace) | 
|  | Result.emplace_back("(anonymous namespace)"); | 
|  |  | 
|  | if (const char *Str = DIE.getName(DINameKind::LinkageName)) { | 
|  | if (Result.empty() || Result[0] != Str) | 
|  | Result.emplace_back(Str); | 
|  | } | 
|  |  | 
|  | return Result; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyNameIndexEntries( | 
|  | const DWARFDebugNames::NameIndex &NI, | 
|  | const DWARFDebugNames::NameTableEntry &NTE) { | 
|  | // Verifying type unit indexes not supported. | 
|  | if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0) | 
|  | return 0; | 
|  |  | 
|  | const char *CStr = NTE.getString(); | 
|  | if (!CStr) { | 
|  | error() << formatv( | 
|  | "Name Index @ {0:x}: Unable to get string associated with name {1}.\n", | 
|  | NI.getUnitOffset(), NTE.getIndex()); | 
|  | return 1; | 
|  | } | 
|  | StringRef Str(CStr); | 
|  |  | 
|  | unsigned NumErrors = 0; | 
|  | unsigned NumEntries = 0; | 
|  | uint32_t EntryID = NTE.getEntryOffset(); | 
|  | uint32_t NextEntryID = EntryID; | 
|  | Expected<DWARFDebugNames::Entry> EntryOr = NI.getEntry(&NextEntryID); | 
|  | for (; EntryOr; ++NumEntries, EntryID = NextEntryID, | 
|  | EntryOr = NI.getEntry(&NextEntryID)) { | 
|  | uint32_t CUIndex = *EntryOr->getCUIndex(); | 
|  | if (CUIndex > NI.getCUCount()) { | 
|  | error() << formatv("Name Index @ {0:x}: Entry @ {1:x} contains an " | 
|  | "invalid CU index ({2}).\n", | 
|  | NI.getUnitOffset(), EntryID, CUIndex); | 
|  | ++NumErrors; | 
|  | continue; | 
|  | } | 
|  | uint32_t CUOffset = NI.getCUOffset(CUIndex); | 
|  | uint64_t DIEOffset = CUOffset + *EntryOr->getDIEUnitOffset(); | 
|  | DWARFDie DIE = DCtx.getDIEForOffset(DIEOffset); | 
|  | if (!DIE) { | 
|  | error() << formatv("Name Index @ {0:x}: Entry @ {1:x} references a " | 
|  | "non-existing DIE @ {2:x}.\n", | 
|  | NI.getUnitOffset(), EntryID, DIEOffset); | 
|  | ++NumErrors; | 
|  | continue; | 
|  | } | 
|  | if (DIE.getDwarfUnit()->getOffset() != CUOffset) { | 
|  | error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched CU of " | 
|  | "DIE @ {2:x}: index - {3:x}; debug_info - {4:x}.\n", | 
|  | NI.getUnitOffset(), EntryID, DIEOffset, CUOffset, | 
|  | DIE.getDwarfUnit()->getOffset()); | 
|  | ++NumErrors; | 
|  | } | 
|  | if (DIE.getTag() != EntryOr->tag()) { | 
|  | error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched Tag of " | 
|  | "DIE @ {2:x}: index - {3}; debug_info - {4}.\n", | 
|  | NI.getUnitOffset(), EntryID, DIEOffset, EntryOr->tag(), | 
|  | DIE.getTag()); | 
|  | ++NumErrors; | 
|  | } | 
|  |  | 
|  | auto EntryNames = getNames(DIE); | 
|  | if (!is_contained(EntryNames, Str)) { | 
|  | error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched Name " | 
|  | "of DIE @ {2:x}: index - {3}; debug_info - {4}.\n", | 
|  | NI.getUnitOffset(), EntryID, DIEOffset, Str, | 
|  | make_range(EntryNames.begin(), EntryNames.end())); | 
|  | ++NumErrors; | 
|  | } | 
|  | } | 
|  | handleAllErrors(EntryOr.takeError(), | 
|  | [&](const DWARFDebugNames::SentinelError &) { | 
|  | if (NumEntries > 0) | 
|  | return; | 
|  | error() << formatv("Name Index @ {0:x}: Name {1} ({2}) is " | 
|  | "not associated with any entries.\n", | 
|  | NI.getUnitOffset(), NTE.getIndex(), Str); | 
|  | ++NumErrors; | 
|  | }, | 
|  | [&](const ErrorInfoBase &Info) { | 
|  | error() | 
|  | << formatv("Name Index @ {0:x}: Name {1} ({2}): {3}\n", | 
|  | NI.getUnitOffset(), NTE.getIndex(), Str, | 
|  | Info.message()); | 
|  | ++NumErrors; | 
|  | }); | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | static bool isVariableIndexable(const DWARFDie &Die, DWARFContext &DCtx) { | 
|  | Optional<DWARFFormValue> Location = Die.findRecursively(DW_AT_location); | 
|  | if (!Location) | 
|  | return false; | 
|  |  | 
|  | auto ContainsInterestingOperators = [&](StringRef D) { | 
|  | DWARFUnit *U = Die.getDwarfUnit(); | 
|  | DataExtractor Data(D, DCtx.isLittleEndian(), U->getAddressByteSize()); | 
|  | DWARFExpression Expression(Data, U->getVersion(), U->getAddressByteSize()); | 
|  | return any_of(Expression, [](DWARFExpression::Operation &Op) { | 
|  | return !Op.isError() && (Op.getCode() == DW_OP_addr || | 
|  | Op.getCode() == DW_OP_form_tls_address || | 
|  | Op.getCode() == DW_OP_GNU_push_tls_address); | 
|  | }); | 
|  | }; | 
|  |  | 
|  | if (Optional<ArrayRef<uint8_t>> Expr = Location->getAsBlock()) { | 
|  | // Inlined location. | 
|  | if (ContainsInterestingOperators(toStringRef(*Expr))) | 
|  | return true; | 
|  | } else if (Optional<uint64_t> Offset = Location->getAsSectionOffset()) { | 
|  | // Location list. | 
|  | if (const DWARFDebugLoc *DebugLoc = DCtx.getDebugLoc()) { | 
|  | if (const DWARFDebugLoc::LocationList *LocList = | 
|  | DebugLoc->getLocationListAtOffset(*Offset)) { | 
|  | if (any_of(LocList->Entries, [&](const DWARFDebugLoc::Entry &E) { | 
|  | return ContainsInterestingOperators({E.Loc.data(), E.Loc.size()}); | 
|  | })) | 
|  | return true; | 
|  | } | 
|  | } | 
|  | } | 
|  | return false; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyNameIndexCompleteness( | 
|  | const DWARFDie &Die, const DWARFDebugNames::NameIndex &NI) { | 
|  |  | 
|  | // First check, if the Die should be indexed. The code follows the DWARF v5 | 
|  | // wording as closely as possible. | 
|  |  | 
|  | // "All non-defining declarations (that is, debugging information entries | 
|  | // with a DW_AT_declaration attribute) are excluded." | 
|  | if (Die.find(DW_AT_declaration)) | 
|  | return 0; | 
|  |  | 
|  | // "DW_TAG_namespace debugging information entries without a DW_AT_name | 
|  | // attribute are included with the name “(anonymous namespace)”. | 
|  | // All other debugging information entries without a DW_AT_name attribute | 
|  | // are excluded." | 
|  | // "If a subprogram or inlined subroutine is included, and has a | 
|  | // DW_AT_linkage_name attribute, there will be an additional index entry for | 
|  | // the linkage name." | 
|  | auto EntryNames = getNames(Die); | 
|  | if (EntryNames.empty()) | 
|  | return 0; | 
|  |  | 
|  | // We deviate from the specification here, which says: | 
|  | // "The name index must contain an entry for each debugging information entry | 
|  | // that defines a named subprogram, label, variable, type, or namespace, | 
|  | // subject to ..." | 
|  | // Instead whitelisting all TAGs representing a "type" or a "subprogram", to | 
|  | // make sure we catch any missing items, we instead blacklist all TAGs that we | 
|  | // know shouldn't be indexed. | 
|  | switch (Die.getTag()) { | 
|  | // Compile unit has a name but it shouldn't be indexed. | 
|  | case DW_TAG_compile_unit: | 
|  | return 0; | 
|  |  | 
|  | // Function and template parameters are not globally visible, so we shouldn't | 
|  | // index them. | 
|  | case DW_TAG_formal_parameter: | 
|  | case DW_TAG_template_value_parameter: | 
|  | case DW_TAG_template_type_parameter: | 
|  | case DW_TAG_GNU_template_parameter_pack: | 
|  | case DW_TAG_GNU_template_template_param: | 
|  | return 0; | 
|  |  | 
|  | // Object members aren't globally visible. | 
|  | case DW_TAG_member: | 
|  | return 0; | 
|  |  | 
|  | // According to a strict reading of the specification, enumerators should not | 
|  | // be indexed (and LLVM currently does not do that). However, this causes | 
|  | // problems for the debuggers, so we may need to reconsider this. | 
|  | case DW_TAG_enumerator: | 
|  | return 0; | 
|  |  | 
|  | // Imported declarations should not be indexed according to the specification | 
|  | // and LLVM currently does not do that. | 
|  | case DW_TAG_imported_declaration: | 
|  | return 0; | 
|  |  | 
|  | // "DW_TAG_subprogram, DW_TAG_inlined_subroutine, and DW_TAG_label debugging | 
|  | // information entries without an address attribute (DW_AT_low_pc, | 
|  | // DW_AT_high_pc, DW_AT_ranges, or DW_AT_entry_pc) are excluded." | 
|  | case DW_TAG_subprogram: | 
|  | case DW_TAG_inlined_subroutine: | 
|  | case DW_TAG_label: | 
|  | if (Die.findRecursively( | 
|  | {DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_entry_pc})) | 
|  | break; | 
|  | return 0; | 
|  |  | 
|  | // "DW_TAG_variable debugging information entries with a DW_AT_location | 
|  | // attribute that includes a DW_OP_addr or DW_OP_form_tls_address operator are | 
|  | // included; otherwise, they are excluded." | 
|  | // | 
|  | // LLVM extension: We also add DW_OP_GNU_push_tls_address to this list. | 
|  | case DW_TAG_variable: | 
|  | if (isVariableIndexable(Die, DCtx)) | 
|  | break; | 
|  | return 0; | 
|  |  | 
|  | default: | 
|  | break; | 
|  | } | 
|  |  | 
|  | // Now we know that our Die should be present in the Index. Let's check if | 
|  | // that's the case. | 
|  | unsigned NumErrors = 0; | 
|  | uint64_t DieUnitOffset = Die.getOffset() - Die.getDwarfUnit()->getOffset(); | 
|  | for (StringRef Name : EntryNames) { | 
|  | if (none_of(NI.equal_range(Name), [&](const DWARFDebugNames::Entry &E) { | 
|  | return E.getDIEUnitOffset() == DieUnitOffset; | 
|  | })) { | 
|  | error() << formatv("Name Index @ {0:x}: Entry for DIE @ {1:x} ({2}) with " | 
|  | "name {3} missing.\n", | 
|  | NI.getUnitOffset(), Die.getOffset(), Die.getTag(), | 
|  | Name); | 
|  | ++NumErrors; | 
|  | } | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | unsigned DWARFVerifier::verifyDebugNames(const DWARFSection &AccelSection, | 
|  | const DataExtractor &StrData) { | 
|  | unsigned NumErrors = 0; | 
|  | DWARFDataExtractor AccelSectionData(DCtx.getDWARFObj(), AccelSection, | 
|  | DCtx.isLittleEndian(), 0); | 
|  | DWARFDebugNames AccelTable(AccelSectionData, StrData); | 
|  |  | 
|  | OS << "Verifying .debug_names...\n"; | 
|  |  | 
|  | // This verifies that we can read individual name indices and their | 
|  | // abbreviation tables. | 
|  | if (Error E = AccelTable.extract()) { | 
|  | error() << toString(std::move(E)) << '\n'; | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | NumErrors += verifyDebugNamesCULists(AccelTable); | 
|  | for (const auto &NI : AccelTable) | 
|  | NumErrors += verifyNameIndexBuckets(NI, StrData); | 
|  | for (const auto &NI : AccelTable) | 
|  | NumErrors += verifyNameIndexAbbrevs(NI); | 
|  |  | 
|  | // Don't attempt Entry validation if any of the previous checks found errors | 
|  | if (NumErrors > 0) | 
|  | return NumErrors; | 
|  | for (const auto &NI : AccelTable) | 
|  | for (DWARFDebugNames::NameTableEntry NTE : NI) | 
|  | NumErrors += verifyNameIndexEntries(NI, NTE); | 
|  |  | 
|  | if (NumErrors > 0) | 
|  | return NumErrors; | 
|  |  | 
|  | for (const std::unique_ptr<DWARFUnit> &U : DCtx.compile_units()) { | 
|  | if (const DWARFDebugNames::NameIndex *NI = | 
|  | AccelTable.getCUNameIndex(U->getOffset())) { | 
|  | auto *CU = cast<DWARFCompileUnit>(U.get()); | 
|  | for (const DWARFDebugInfoEntry &Die : CU->dies()) | 
|  | NumErrors += verifyNameIndexCompleteness(DWARFDie(CU, &Die), *NI); | 
|  | } | 
|  | } | 
|  | return NumErrors; | 
|  | } | 
|  |  | 
|  | bool DWARFVerifier::handleAccelTables() { | 
|  | const DWARFObject &D = DCtx.getDWARFObj(); | 
|  | DataExtractor StrData(D.getStringSection(), DCtx.isLittleEndian(), 0); | 
|  | unsigned NumErrors = 0; | 
|  | if (!D.getAppleNamesSection().Data.empty()) | 
|  | NumErrors += | 
|  | verifyAppleAccelTable(&D.getAppleNamesSection(), &StrData, ".apple_names"); | 
|  | if (!D.getAppleTypesSection().Data.empty()) | 
|  | NumErrors += | 
|  | verifyAppleAccelTable(&D.getAppleTypesSection(), &StrData, ".apple_types"); | 
|  | if (!D.getAppleNamespacesSection().Data.empty()) | 
|  | NumErrors += verifyAppleAccelTable(&D.getAppleNamespacesSection(), &StrData, | 
|  | ".apple_namespaces"); | 
|  | if (!D.getAppleObjCSection().Data.empty()) | 
|  | NumErrors += | 
|  | verifyAppleAccelTable(&D.getAppleObjCSection(), &StrData, ".apple_objc"); | 
|  |  | 
|  | if (!D.getDebugNamesSection().Data.empty()) | 
|  | NumErrors += verifyDebugNames(D.getDebugNamesSection(), StrData); | 
|  | return NumErrors == 0; | 
|  | } | 
|  |  | 
|  | raw_ostream &DWARFVerifier::error() const { return WithColor::error(OS); } | 
|  |  | 
|  | raw_ostream &DWARFVerifier::warn() const { return WithColor::warning(OS); } | 
|  |  | 
|  | raw_ostream &DWARFVerifier::note() const { return WithColor::note(OS); } |