1 //===- DWARFVerifier.h ----------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_DEBUGINFO_DWARF_DWARFVERIFIER_H 10 #define LLVM_DEBUGINFO_DWARF_DWARFVERIFIER_H 11 12 #include "llvm/DebugInfo/DIContext.h" 13 #include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h" 14 #include "llvm/DebugInfo/DWARF/DWARFAddressRange.h" 15 #include "llvm/DebugInfo/DWARF/DWARFDie.h" 16 #include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h" 17 #include <cstdint> 18 #include <map> 19 #include <set> 20 21 namespace llvm { 22 class raw_ostream; 23 struct DWARFAddressRange; 24 class DWARFUnit; 25 class DWARFUnitVector; 26 struct DWARFAttribute; 27 class DWARFContext; 28 class DWARFDataExtractor; 29 class DWARFDebugAbbrev; 30 class DataExtractor; 31 struct DWARFSection; 32 33 class OutputCategoryAggregator { 34 private: 35 std::map<std::string, unsigned> Aggregation; 36 bool IncludeDetail; 37 38 public: 39 OutputCategoryAggregator(bool includeDetail = false) IncludeDetail(includeDetail)40 : IncludeDetail(includeDetail) {} ShowDetail(bool showDetail)41 void ShowDetail(bool showDetail) { IncludeDetail = showDetail; } GetNumCategories()42 size_t GetNumCategories() const { return Aggregation.size(); } 43 void Report(StringRef s, std::function<void()> detailCallback); 44 void EnumerateResults(std::function<void(StringRef, unsigned)> handleCounts); 45 }; 46 47 /// A class that verifies DWARF debug information given a DWARF Context. 48 class DWARFVerifier { 49 public: 50 /// A class that keeps the address range information for a single DIE. 51 struct DieRangeInfo { 52 DWARFDie Die; 53 54 /// Sorted DWARFAddressRanges. 55 std::vector<DWARFAddressRange> Ranges; 56 57 /// Sorted DWARFAddressRangeInfo. 58 std::set<DieRangeInfo> Children; 59 60 DieRangeInfo() = default; DieRangeInfoDieRangeInfo61 DieRangeInfo(DWARFDie Die) : Die(Die) {} 62 63 /// Used for unit testing. DieRangeInfoDieRangeInfo64 DieRangeInfo(std::vector<DWARFAddressRange> Ranges) 65 : Ranges(std::move(Ranges)) {} 66 67 typedef std::set<DieRangeInfo>::const_iterator die_range_info_iterator; 68 69 /// Inserts the address range. If the range overlaps with an existing 70 /// range, the range that it overlaps with will be returned and the two 71 /// address ranges will be unioned together in "Ranges". 72 /// 73 /// This is used for finding overlapping ranges in the DW_AT_ranges 74 /// attribute of a DIE. It is also used as a set of address ranges that 75 /// children address ranges must all be contained in. 76 std::optional<DWARFAddressRange> insert(const DWARFAddressRange &R); 77 78 /// Inserts the address range info. If any of its ranges overlaps with a 79 /// range in an existing range info, the range info is *not* added and an 80 /// iterator to the overlapping range info. 81 /// 82 /// This is used for finding overlapping children of the same DIE. 83 die_range_info_iterator insert(const DieRangeInfo &RI); 84 85 /// Return true if ranges in this object contains all ranges within RHS. 86 bool contains(const DieRangeInfo &RHS) const; 87 88 /// Return true if any range in this object intersects with any range in 89 /// RHS. 90 bool intersects(const DieRangeInfo &RHS) const; 91 }; 92 93 private: 94 raw_ostream &OS; 95 DWARFContext &DCtx; 96 DIDumpOptions DumpOpts; 97 uint32_t NumDebugLineErrors = 0; 98 OutputCategoryAggregator ErrorCategory; 99 // Used to relax some checks that do not currently work portably 100 bool IsObjectFile; 101 bool IsMachOObject; 102 using ReferenceMap = std::map<uint64_t, std::set<uint64_t>>; 103 104 raw_ostream &error() const; 105 raw_ostream &warn() const; 106 raw_ostream ¬e() const; 107 raw_ostream &dump(const DWARFDie &Die, unsigned indent = 0) const; 108 109 /// Verifies the abbreviations section. 110 /// 111 /// This function currently checks that: 112 /// --No abbreviation declaration has more than one attributes with the same 113 /// name. 114 /// 115 /// \param Abbrev Pointer to the abbreviations section we are verifying 116 /// Abbrev can be a pointer to either .debug_abbrev or debug_abbrev.dwo. 117 /// 118 /// \returns The number of errors that occurred during verification. 119 unsigned verifyAbbrevSection(const DWARFDebugAbbrev *Abbrev); 120 121 /// Verifies the header of a unit in a .debug_info or .debug_types section. 122 /// 123 /// This function currently checks for: 124 /// - Unit is in 32-bit DWARF format. The function can be modified to 125 /// support 64-bit format. 126 /// - The DWARF version is valid 127 /// - The unit type is valid (if unit is in version >=5) 128 /// - The unit doesn't extend beyond the containing section 129 /// - The address size is valid 130 /// - The offset in the .debug_abbrev section is valid 131 /// 132 /// \param DebugInfoData The section data 133 /// \param Offset A reference to the offset start of the unit. The offset will 134 /// be updated to point to the next unit in the section 135 /// \param UnitIndex The index of the unit to be verified 136 /// \param UnitType A reference to the type of the unit 137 /// \param isUnitDWARF64 A reference to a flag that shows whether the unit is 138 /// in 64-bit format. 139 /// 140 /// \returns true if the header is verified successfully, false otherwise. 141 bool verifyUnitHeader(const DWARFDataExtractor DebugInfoData, 142 uint64_t *Offset, unsigned UnitIndex, uint8_t &UnitType, 143 bool &isUnitDWARF64); 144 bool verifyName(const DWARFDie &Die); 145 146 /// Verifies the header of a unit in a .debug_info or .debug_types section. 147 /// 148 /// This function currently verifies: 149 /// - The debug info attributes. 150 /// - The debug info form=s. 151 /// - The presence of a root DIE. 152 /// - That the root DIE is a unit DIE. 153 /// - If a unit type is provided, that the unit DIE matches the unit type. 154 /// - The DIE ranges. 155 /// - That call site entries are only nested within subprograms with a 156 /// DW_AT_call attribute. 157 /// 158 /// \param Unit The DWARF Unit to verify. 159 /// 160 /// \returns The number of errors that occurred during verification. 161 unsigned verifyUnitContents(DWARFUnit &Unit, 162 ReferenceMap &UnitLocalReferences, 163 ReferenceMap &CrossUnitReferences); 164 165 /// Verifies the unit headers and contents in a .debug_info or .debug_types 166 /// section. 167 /// 168 /// \param S The DWARF Section to verify. 169 /// 170 /// \returns The number of errors that occurred during verification. 171 unsigned verifyUnitSection(const DWARFSection &S); 172 unsigned verifyUnits(const DWARFUnitVector &Units); 173 174 unsigned verifyIndex(StringRef Name, DWARFSectionKind SectionKind, 175 StringRef Index); 176 177 /// Verifies that a call site entry is nested within a subprogram with a 178 /// DW_AT_call attribute. 179 /// 180 /// \returns Number of errors that occurred during verification. 181 unsigned verifyDebugInfoCallSite(const DWARFDie &Die); 182 183 /// Verify that all Die ranges are valid. 184 /// 185 /// This function currently checks for: 186 /// - cases in which lowPC >= highPC 187 /// 188 /// \returns Number of errors that occurred during verification. 189 unsigned verifyDieRanges(const DWARFDie &Die, DieRangeInfo &ParentRI); 190 191 /// Verifies the attribute's DWARF attribute and its value. 192 /// 193 /// This function currently checks for: 194 /// - DW_AT_ranges values is a valid .debug_ranges offset 195 /// - DW_AT_stmt_list is a valid .debug_line offset 196 /// 197 /// \param Die The DWARF DIE that owns the attribute value 198 /// \param AttrValue The DWARF attribute value to check 199 /// 200 /// \returns NumErrors The number of errors occurred during verification of 201 /// attributes' values in a unit 202 unsigned verifyDebugInfoAttribute(const DWARFDie &Die, 203 DWARFAttribute &AttrValue); 204 205 /// Verifies the attribute's DWARF form. 206 /// 207 /// This function currently checks for: 208 /// - All DW_FORM_ref values that are CU relative have valid CU offsets 209 /// - All DW_FORM_ref_addr values have valid section offsets 210 /// - All DW_FORM_strp values have valid .debug_str offsets 211 /// 212 /// \param Die The DWARF DIE that owns the attribute value 213 /// \param AttrValue The DWARF attribute value to check 214 /// 215 /// \returns NumErrors The number of errors occurred during verification of 216 /// attributes' forms in a unit 217 unsigned verifyDebugInfoForm(const DWARFDie &Die, DWARFAttribute &AttrValue, 218 ReferenceMap &UnitLocalReferences, 219 ReferenceMap &CrossUnitReferences); 220 221 /// Verifies the all valid references that were found when iterating through 222 /// all of the DIE attributes. 223 /// 224 /// This function will verify that all references point to DIEs whose DIE 225 /// offset matches. This helps to ensure if a DWARF link phase moved things 226 /// around, that it doesn't create invalid references by failing to relocate 227 /// CU relative and absolute references. 228 /// 229 /// \returns NumErrors The number of errors occurred during verification of 230 /// references for the .debug_info and .debug_types sections 231 unsigned verifyDebugInfoReferences( 232 const ReferenceMap &, 233 llvm::function_ref<DWARFUnit *(uint64_t)> GetUnitForDieOffset); 234 235 /// Verify the DW_AT_stmt_list encoding and value and ensure that no 236 /// compile units that have the same DW_AT_stmt_list value. 237 void verifyDebugLineStmtOffsets(); 238 239 /// Verify that all of the rows in the line table are valid. 240 /// 241 /// This function currently checks for: 242 /// - addresses within a sequence that decrease in value 243 /// - invalid file indexes 244 void verifyDebugLineRows(); 245 246 /// Verify that an Apple-style accelerator table is valid. 247 /// 248 /// This function currently checks that: 249 /// - The fixed part of the header fits in the section 250 /// - The size of the section is as large as what the header describes 251 /// - There is at least one atom 252 /// - The form for each atom is valid 253 /// - The tag for each DIE in the table is valid 254 /// - The buckets have a valid index, or they are empty 255 /// - Each hashdata offset is valid 256 /// - Each DIE is valid 257 /// 258 /// \param AccelSection pointer to the section containing the acceleration table 259 /// \param StrData pointer to the string section 260 /// \param SectionName the name of the table we're verifying 261 /// 262 /// \returns The number of errors occurred during verification 263 unsigned verifyAppleAccelTable(const DWARFSection *AccelSection, 264 DataExtractor *StrData, 265 const char *SectionName); 266 267 unsigned verifyDebugNamesCULists(const DWARFDebugNames &AccelTable); 268 unsigned verifyNameIndexBuckets(const DWARFDebugNames::NameIndex &NI, 269 const DataExtractor &StrData); 270 unsigned verifyNameIndexAbbrevs(const DWARFDebugNames::NameIndex &NI); 271 unsigned verifyNameIndexAttribute(const DWARFDebugNames::NameIndex &NI, 272 const DWARFDebugNames::Abbrev &Abbr, 273 DWARFDebugNames::AttributeEncoding AttrEnc); 274 unsigned verifyNameIndexEntries(const DWARFDebugNames::NameIndex &NI, 275 const DWARFDebugNames::NameTableEntry &NTE); 276 unsigned verifyNameIndexCompleteness(const DWARFDie &Die, 277 const DWARFDebugNames::NameIndex &NI); 278 279 /// Verify that the DWARF v5 accelerator table is valid. 280 /// 281 /// This function currently checks that: 282 /// - Headers individual Name Indices fit into the section and can be parsed. 283 /// - Abbreviation tables can be parsed and contain valid index attributes 284 /// with correct form encodings. 285 /// - The CU lists reference existing compile units. 286 /// - The buckets have a valid index, or they are empty. 287 /// - All names are reachable via the hash table (they have the correct hash, 288 /// and the hash is in the correct bucket). 289 /// - Information in the index entries is complete (all required entries are 290 /// present) and consistent with the debug_info section DIEs. 291 /// 292 /// \param AccelSection section containing the acceleration table 293 /// \param StrData string section 294 /// 295 /// \returns The number of errors occurred during verification 296 unsigned verifyDebugNames(const DWARFSection &AccelSection, 297 const DataExtractor &StrData); 298 299 public: 300 DWARFVerifier(raw_ostream &S, DWARFContext &D, 301 DIDumpOptions DumpOpts = DIDumpOptions::getForSingleDIE()); 302 303 /// Verify the information in any of the following sections, if available: 304 /// .debug_abbrev, debug_abbrev.dwo 305 /// 306 /// Any errors are reported to the stream that was this object was 307 /// constructed with. 308 /// 309 /// \returns true if .debug_abbrev and .debug_abbrev.dwo verify successfully, 310 /// false otherwise. 311 bool handleDebugAbbrev(); 312 313 /// Verify the information in the .debug_info and .debug_types sections. 314 /// 315 /// Any errors are reported to the stream that this object was 316 /// constructed with. 317 /// 318 /// \returns true if all sections verify successfully, false otherwise. 319 bool handleDebugInfo(); 320 321 /// Verify the information in the .debug_cu_index section. 322 /// 323 /// Any errors are reported to the stream that was this object was 324 /// constructed with. 325 /// 326 /// \returns true if the .debug_cu_index verifies successfully, false 327 /// otherwise. 328 bool handleDebugCUIndex(); 329 330 /// Verify the information in the .debug_tu_index section. 331 /// 332 /// Any errors are reported to the stream that was this object was 333 /// constructed with. 334 /// 335 /// \returns true if the .debug_tu_index verifies successfully, false 336 /// otherwise. 337 bool handleDebugTUIndex(); 338 339 /// Verify the information in the .debug_line section. 340 /// 341 /// Any errors are reported to the stream that was this object was 342 /// constructed with. 343 /// 344 /// \returns true if the .debug_line verifies successfully, false otherwise. 345 bool handleDebugLine(); 346 347 /// Verify the information in accelerator tables, if they exist. 348 /// 349 /// Any errors are reported to the stream that was this object was 350 /// constructed with. 351 /// 352 /// \returns true if the existing Apple-style accelerator tables verify 353 /// successfully, false otherwise. 354 bool handleAccelTables(); 355 356 /// Verify the information in the .debug_str_offsets[.dwo]. 357 /// 358 /// Any errors are reported to the stream that was this object was 359 /// constructed with. 360 /// 361 /// \returns true if the .debug_line verifies successfully, false otherwise. 362 bool handleDebugStrOffsets(); 363 bool verifyDebugStrOffsets(std::optional<dwarf::DwarfFormat> LegacyFormat, 364 StringRef SectionName, const DWARFSection &Section, 365 StringRef StrData); 366 367 /// Emits any aggregate information collected, depending on the dump options 368 void summarize(); 369 }; 370 371 static inline bool operator<(const DWARFVerifier::DieRangeInfo &LHS, 372 const DWARFVerifier::DieRangeInfo &RHS) { 373 return std::tie(LHS.Ranges, LHS.Die) < std::tie(RHS.Ranges, RHS.Die); 374 } 375 376 } // end namespace llvm 377 378 #endif // LLVM_DEBUGINFO_DWARF_DWARFVERIFIER_H 379