[DWARF] Verification of the validity of the hash data offset and hash data DIEs in the the .apple_names section.

[sgravani]

Summary

This patch adds checks for the validity of the hash data offset in the .apple_names accelerator table.
It also adds checks for the validity of the DIEs in the actual hash data.

[aprantl]

lib/DebugInfo/DWARF/DWARFVerifier.cpp

313

. at the end

318

should we just say 64 here?

test/tools/llvm-dwarfdump/X86/apple_names_verify_hashdata_offset.s

3 ↗

(On Diff #103085)

Since the verifier continues on error, could this test be merged with any of the existing .apple_names tests?

[sgravani]

Added more checks for the validity of the .apple_names section.

[friss]

Here's a first round of comments.

include/llvm/BinaryFormat/Dwarf.h

65–66

Why is this not a con unit32_t? I feel like the comment should explain what it is too.

include/llvm/DebugInfo/DWARF/DWARFContext.h

279–280 ↗

(On Diff #103614)

This needs a comment, and I'm not fond of the name. It's not really descriptive.

include/llvm/DebugInfo/DWARF/DWARFFormValue.h

96–98 ↗

(On Diff #103614)

I can see the usefulness of the getAsReference helper, but it should really return an Optional<uint64_t>. I think you should just use getAsUnsignedConstant() instead of adding an unchecked version.

include/llvm/DebugInfo/DWARF/DWARFUnit.h

301–310 ↗

(On Diff #103614)

DIEs are sorted by offset, so this should use some kind of binary search. Also, I think the API is overly constrained. What about "DWARFDie getDIEAtOffset(nuint32_t offset)" ? It would return an invalid DwarfDIE if that offset is not valid.

lib/DebugInfo/DWARF/DWARFFormValue.cpp

359–360 ↗

(On Diff #103614)

All those added cases don't change the behavior, just leave this file as it is.

lib/Support/DataExtractor.cpp

131–137 ↗

(On Diff #103614)

This could be implemented in terms of getCStr()

[sgravani]

Addressed reviewer's comments.

[friss]

This looks much better!

include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h

58–60

Can this be changed into just one
ArrayRef<std::pair<AtomType, Form>> getAtomsDesc()
?

I find it cleaner that the piecewise interface.

61

It's not obvious what the function does, what the argument is and what it returns. Please add a doxygen comment.

lib/DebugInfo/DWARF/DWARFVerifier.cpp

331–337

The error doesn't seem to reflect the test. Also, unless I'm missing something, you should be able to do this test once outside of the loop.

346–349

I would return here. I think this is a fatal error. There's no point in continuing to try to decode the bitstream when you failed to read a piece of it.

test/tools/llvm-dwarfdump/X86/apple_names_verify_buckets_hashdataoffset.s

107 ↗

(On Diff #104024)

Do you need all the other sections? Wouldn't it work just with the __apple_names section?

[sgravani]

Added isSupportedForm() function in DWARFFormValue class that will help us get more detailed error messages
when reading the Atoms in apple_names (and in future any accelerator table) during verification.

Addressed reviewer's comments.

[friss]

Some more comments:

include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h

58

you don't really need this, you can do getAtomsDesc().size();

lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp

75–76

for (auto Atom : getAtomDesc()) {
    AtomType Type = Atom.first;
    Form Form = Atom.second;
...

82

Either you add a check here that the Optional is populated, or you check before iterating that the description of the die_offset has a form that can be decoded by getAsUnsignedConstant(). As written this can crash.

[sgravani]

Added test on an object file without errors in the .apple_names section.
Addressed comments.

include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h

58

...good point

[friss]

This LGTM. Few nitpicks you might wanna address before committing:

lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp

84

I think you can do that test only once for the whole table instead of at each iteration.

test/tools/llvm-dwarfdump/X86/apple_names.test

1–5

No big deal, but I would just add these checks to the test/DebugInfo/dwarfdump-accel.test test.

[sgravani]

Closes with commit: https://reviews.llvm.org/rL306735

include/llvm/BinaryFormat/Dwarf.h

enum LLVMConstants : uint32_t {
   DWARF_VENDOR_MIPS = 6
 };
 
 // Special ID values that distinguish a CIE from a FDE in DWARF CFI.
 // Not inside an enum because a 64-bit value is needed.
 const uint32_t DW_CIE_ID = UINT32_MAX;
 const uint64_t DW64_CIE_ID = UINT64_MAX;
 
+// Identifier of an invalid DIE offset in the .debug_info section.
+const uint32_t DW_INVALID_OFFSET = UINT32_MAX;
+
 enum Tag : uint16_t {
 #define HANDLE_DW_TAG(ID, NAME, VERSION, VENDOR) DW_TAG_##NAME = ID,
 #include "llvm/BinaryFormat/Dwarf.def"
   DW_TAG_lo_user = 0x4080,
   DW_TAG_hi_user = 0xffff,
   DW_TAG_user_base = 0x1000 // Recommended base for user tags.
 };
 

include/llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h

DWARFAcceleratorTable(DataExtractor AccelSection, DataExtractor StringSection,
                         const RelocAddrMap &Relocs)
     : AccelSection(AccelSection), StringSection(StringSection), Relocs(Relocs) {}
 
   bool extract();
   uint32_t getNumBuckets();
   uint32_t getNumHashes();
   uint32_t getSizeHdr();
   uint32_t getHeaderDataLength();
+  ArrayRef<std::pair<HeaderData::AtomType, HeaderData::Form>> getAtomsDesc();
+
+  /// Return information related to the DWARF DIE we're looking for when
+  /// performing a lookup by name.
+  ///
+  /// \param HashDataOffset an offset into the hash data table
+  /// \returns DIEOffset the offset into the .debug_info section for the DIE
+  /// related to the input hash data offset. Currently this function returns
+  /// only the DIEOffset but it can be modified to return more data regarding
+  /// the DIE
+  uint32_t readAtoms(uint32_t &HashDataOffset);
   void dump(raw_ostream &OS) const;
 };
 
 } // end namespace llvm
 
 #endif // LLVM_DEBUGINFO_DWARFACCELERATORTABLE_H

lib/DebugInfo/DWARF/DWARFAcceleratorTable.cpp

 
 uint32_t DWARFAcceleratorTable::getNumBuckets() { return Hdr.NumBuckets; }
 uint32_t DWARFAcceleratorTable::getNumHashes() { return Hdr.NumHashes; }
 uint32_t DWARFAcceleratorTable::getSizeHdr() { return sizeof(Hdr); }
 uint32_t DWARFAcceleratorTable::getHeaderDataLength() {
   return Hdr.HeaderDataLength;
 }
 
+ArrayRef<std::pair<DWARFAcceleratorTable::HeaderData::AtomType,
+                   DWARFAcceleratorTable::HeaderData::Form>>
+DWARFAcceleratorTable::getAtomsDesc() {
+  return HdrData.Atoms;
+}
+
+bool isSupportedForm(DWARFFormValue FormValue) {
+  if ((!FormValue.isFormClass(DWARFFormValue::FC_Constant) &&
+       !FormValue.isFormClass(DWARFFormValue::FC_Flag)) ||
+      FormValue.getForm() == dwarf::DW_FORM_sdata)
+    return false;
+  return true;
+}
+
+uint32_t DWARFAcceleratorTable::readAtoms(uint32_t &HashDataOffset) {
+  uint32_t DieOffset = dwarf::DW_INVALID_OFFSET;
+
+  for (auto Atom : getAtomsDesc()) {
+    DWARFFormValue FormValue(Atom.second);
+    if (isSupportedForm(FormValue)) {
+      FormValue.extractValue(AccelSection, &HashDataOffset, NULL);
+      switch (Atom.first) {
+      case dwarf::DW_ATOM_die_offset:
+        DieOffset = *FormValue.getAsUnsignedConstant();
+        break;
+      default:
+        break;
+      }
+    } else {
+      HashDataOffset = dwarf::DW_INVALID_OFFSET;
+    }
+  }
+  return DieOffset;
+}
+
 LLVM_DUMP_METHOD void DWARFAcceleratorTable::dump(raw_ostream &OS) const {
   // Dump the header.
   OS << "Magic = " << format("0x%08x", Hdr.Magic) << '\n'
      << "Version = " << format("0x%04x", Hdr.Version) << '\n'
      << "Hash function = " << format("0x%08x", Hdr.HashFunction) << '\n'
      << "Bucket count = " << Hdr.NumBuckets << '\n'
      << "Hashes count = " << Hdr.NumHashes << '\n'
      << "HeaderData length = " << Hdr.HeaderDataLength << '\n'

lib/DebugInfo/DWARF/DWARFVerifier.cpp

DWARFAcceleratorTable AppleNames(AppleNamesSection, StrData,
                                    DCtx.getAppleNamesSection().Relocs);
 
   if (!AppleNames.extract()) {
     return true;
   }
 
   OS << "Verifying .apple_names...\n";
 
-  // Verify that all buckets have a valid hash index or are empty
+  // Verify that all buckets have a valid hash index or are empty.
   uint32_t NumBuckets = AppleNames.getNumBuckets();
   uint32_t NumHashes = AppleNames.getNumHashes();
 
   uint32_t BucketsOffset =
       AppleNames.getSizeHdr() + AppleNames.getHeaderDataLength();
+  uint32_t HashesBase = BucketsOffset + NumBuckets * 4;
+  uint32_t OffsetsBase = HashesBase + NumHashes * 4;
 
   for (uint32_t BucketIdx = 0; BucketIdx < NumBuckets; ++BucketIdx) {
     uint32_t HashIdx = AppleNamesSection.getU32(&BucketsOffset);
     if (HashIdx >= NumHashes && HashIdx != UINT32_MAX) {
-      OS << format("error: Bucket[%d] has invalid hash index: [%d]\n",
-                   BucketIdx, HashIdx);
+      OS << format("error: Bucket[%d] has invalid hash index: %u\n", BucketIdx,
+                   HashIdx);
       ++NumAppleNamesErrors;
     }
   }
+
+  uint32_t NumAtoms = AppleNames.getAtomsDesc().size();
+  if (NumAtoms == 0) {
+    OS << "error: no atoms; failed to read HashData\n";
+    ++NumAppleNamesErrors;
+    return false;
+  }
+
+  for (uint32_t HashIdx = 0; HashIdx < NumHashes; ++HashIdx) {
+    uint32_t HashOffset = HashesBase + 4 * HashIdx;
+    uint32_t DataOffset = OffsetsBase + 4 * HashIdx;
+    uint32_t Hash = AppleNamesSection.getU32(&HashOffset);
+    uint32_t HashDataOffset = AppleNamesSection.getU32(&DataOffset);
+    if (!AppleNamesSection.isValidOffsetForDataOfSize(HashDataOffset,
+                                                      sizeof(uint64_t))) {
+      OS << format("error: Hash[%d] has invalid HashData offset: 0x%08x\n",
+                   HashIdx, HashDataOffset);
+      ++NumAppleNamesErrors;
+    }
+
+    uint32_t StrpOffset;
+    uint32_t StringOffset;
+    uint32_t StringCount = 0;
+    uint32_t DieOffset = dwarf::DW_INVALID_OFFSET;
+
+    while ((StrpOffset = AppleNamesSection.getU32(&HashDataOffset)) != 0) {
+      const uint32_t NumHashDataObjects =
+          AppleNamesSection.getU32(&HashDataOffset);
+      for (uint32_t HashDataIdx = 0; HashDataIdx < NumHashDataObjects;
+           ++HashDataIdx) {
+        const uint32_t HashDataOffsetStart = HashDataOffset;
+        DieOffset = AppleNames.readAtoms(HashDataOffset);
+        if (HashDataOffset == dwarf::DW_INVALID_OFFSET) {
+          OS << format(
+              "error: unsupported form; failed to read HashData at 0x%08x\n",
+              HashDataOffsetStart);
+          ++NumAppleNamesErrors;
+          return false;
+        } else if (!DCtx.getDIEForOffset(DieOffset)) {
+          const uint32_t BucketIdx =
+              NumBuckets ? (Hash % NumBuckets) : UINT32_MAX;
+          StringOffset = StrpOffset;
+          const char *Name = StrData.getCStr(&StringOffset);
+          if (!Name)
+            Name = "<NULL>";
+
+          OS << format(
+              "error: .apple_names Bucket[%d] Hash[%d] = 0x%08x "
+              "Str[%u] = 0x%08x "
+              "DIE[%d] = 0x%08x is not a valid DIE offset for \"%s\".\n",
+              BucketIdx, HashIdx, Hash, StringCount, StrpOffset, HashDataIdx,
+              DieOffset, Name);
+
+          ++NumAppleNamesErrors;
+        }
+      }
+      ++StringCount;
+    }
+  }
   return NumAppleNamesErrors == 0;
 }

test/tools/llvm-dwarfdump/X86/apple_names.test

+RUN: llvm-dwarfdump -verify %p/../../../DebugInfo/Inputs/dwarfdump-objc.x86_64.o \
+RUN:     | FileCheck %s
+
+CHECK: Verifying .apple_names
+CHECK-NEXT: No errors.

test/tools/llvm-dwarfdump/X86/apple_names_verify_atoms.s

+# RUN: llvm-mc %s -filetype obj -triple x86_64-apple-darwin -o - \
+# RUN: | not llvm-dwarfdump -verify - \
+# RUN: | FileCheck %s
+
+# CHECK: Verifying .apple_names...
+# CHECK-NEXT: error: no atoms; failed to read HashData
+
+# This test is meant to verify that the -verify option 
+# in llvm-dwarfdump, correctly identifies that there is not Atom.
+# As a result, the hashdata cannot be read.
+
+  .section  __TEXT,__text,regular,pure_instructions
+  .file 1 "basic.c"
+  .comm _i,4,2                  ## @i
+  .comm _j,4,2                  ## @j
+  .section  __DWARF,__debug_str,regular,debug
+Linfo_string:
+  .asciz  "Apple LLVM version 8.1.0 (clang-802.0.35)" ## string offset=0
+  .asciz  "basic.c"               ## string offset=42
+  .asciz  "/Users/sgravani/Development/tests" ## string offset=50
+  .asciz  "i"                     ## string offset=84
+  .asciz  "int"                   ## string offset=86
+  .asciz  "j"                     ## string offset=90
+  
+  .section  __DWARF,__debug_info,regular,debug
+Lsection_info:
+  .section  __DWARF,__apple_names,regular,debug
+Lnames_begin:
+  .long 1212240712              ## Header Magic
+  .short  1                       ## Header Version
+  .short  0                       ## Header Hash Function
+  .long 2                       ## Header Bucket Count
+  .long 2                       ## Header Hash Count
+  .long 12                      ## Header Data Length
+  .long 0                       ## HeaderData Die Offset Base
+  .long 0                       ## HeaderData Atom Count -- error: no atoms; failed to read HashData
+  .short  1                       ## DW_ATOM_die_offset
+  .short  6                       ## DW_FORM_data4
+  .long 0                       ## Bucket 0
+  .long 1                       ## Bucket 1
+  .long 177678                  ## Hash in Bucket 0
+  .long 177679                  ## Hash in Bucket 1
+  .long LNames0-Lnames_begin    ## Offset in Bucket 0
+  .long LNames1-Lnames_begin    ## Offset in Bucket 1
+LNames0:
+  .long 84                      ## i
+  .long 1                       ## Num DIEs
+  .long 30
+  .long 0
+LNames1:
+  .long 90                      ## j
+  .long 1                       ## Num DIEs
+  .long 58
+  .long 0
+
+.subsections_via_symbols
+  .section  __DWARF,__debug_line,regular,debug
+Lsection_line:
+Lline_table_start0:

test/tools/llvm-dwarfdump/X86/apple_names_verify_buckets.s

-# RUN: llvm-mc %s -filetype obj -triple x86_64-apple-darwin -o - \
-# RUN: | not llvm-dwarfdump -verify - \
-# RUN: | FileCheck %s
-
-# CHECK: Verifying .apple_names...
-# CHECK-NEXT: error: Bucket[0] has invalid hash index: [-2]
-
-# This test is meant to verify that the -verify option 
-# in llvm-dwarfdump, correctly identifies
-# an invalid hash index for bucket[0] in the .apple_names section. 
-
-  .section  __TEXT,__text,regular,pure_instructions
-  .file 1 "basic.c"
-  .comm _i,4,2                  ## @i
-  .section  __DWARF,__debug_str,regular,debug
-Linfo_string:
-  .asciz  "basic.c"               ## string offset=42
-  .asciz  "i"                     ## string offset=84
-  .asciz  "int"                   ## string offset=86
-  .section  __DWARF,__debug_loc,regular,debug
-Lsection_debug_loc:
-  .section  __DWARF,__debug_abbrev,regular,debug
-Lsection_abbrev:
-  .byte 1                       ## Abbreviation Code
-  .byte 17                      ## DW_TAG_compile_unit
-  .byte 1                       ## DW_CHILDREN_yes
-  .byte 37                      ## DW_AT_producer
-  .byte 14                      ## DW_FORM_strp
-  .byte 19                      ## DW_AT_language
-  .byte 5                       ## DW_FORM_data2
-  .byte 3                       ## DW_AT_name
-  .byte 14                      ## DW_FORM_strp
-  .byte 16                      ## DW_AT_stmt_list
-  .byte 23                      ## DW_FORM_sec_offset
-  .byte 27                      ## DW_AT_comp_dir
-  .byte 14                      ## DW_FORM_strp
-  .byte 0                       ## EOM(1)
-  .byte 0                       ## EOM(2)
-  .byte 2                       ## Abbreviation Code
-  .byte 52                      ## DW_TAG_variable
-  .byte 0                       ## DW_CHILDREN_no
-  .byte 3                       ## DW_AT_name
-  .byte 14                      ## DW_FORM_strp
-  .byte 73                      ## DW_AT_type
-  .byte 19                      ## DW_FORM_ref4
-  .byte 63                      ## DW_AT_external
-  .byte 25                      ## DW_FORM_flag_present
-  .byte 58                      ## DW_AT_decl_file
-  .byte 11                      ## DW_FORM_data1
-  .byte 59                      ## DW_AT_decl_line
-  .byte 11                      ## DW_FORM_data1
-  .byte 2                       ## DW_AT_location
-  .byte 24                      ## DW_FORM_exprloc
-  .byte 0                       ## EOM(1)
-  .byte 0                       ## EOM(2)
-  .byte 3                       ## Abbreviation Code
-  .byte 36                      ## DW_TAG_base_type
-  .byte 0                       ## DW_CHILDREN_no
-  .byte 3                       ## DW_AT_name
-  .byte 14                      ## DW_FORM_strp
-  .byte 62                      ## DW_AT_encoding
-  .byte 11                      ## DW_FORM_data1
-  .byte 11                      ## DW_AT_byte_size
-  .byte 11                      ## DW_FORM_data1
-  .byte 0                       ## EOM(1)
-  .byte 0                       ## EOM(2)
-  .byte 0                       ## EOM(3)
-  .section  __DWARF,__debug_info,regular,debug
-Lsection_info:
-Lcu_begin0:
-  .long 55                      ## Length of Unit
-  .short  4                       ## DWARF version number
-Lset0 = Lsection_abbrev-Lsection_abbrev ## Offset Into Abbrev. Section
-  .long Lset0
-  .byte 8                       ## Address Size (in bytes)
-  .byte 1                       ## Abbrev [1] 0xb:0x30 DW_TAG_compile_unit
-  .long 0                       ## DW_AT_producer
-  .short  12                      ## DW_AT_language
-  .long 42                      ## DW_AT_name
-Lset1 = Lline_table_start0-Lsection_line ## DW_AT_stmt_list
-  .long Lset1
-  .long 50                      ## DW_AT_comp_dir
-  .byte 2                       ## Abbrev [2] 0x1e:0x15 DW_TAG_variable
-  .long 84                      ## DW_AT_name
-  .long 51                      ## DW_AT_type
-                                        ## DW_AT_external
-  .byte 1                       ## DW_AT_decl_file
-  .byte 1                       ## DW_AT_decl_line
-  .byte 9                       ## DW_AT_location
-  .byte 3
-  .quad _i
-  .byte 3                       ## Abbrev [3] 0x33:0x7 DW_TAG_base_type
-  .long 86                      ## DW_AT_name
-  .byte 5                       ## DW_AT_encoding
-  .byte 4                       ## DW_AT_byte_size
-  .byte 0                       ## End Of Children Mark
-  .section  __DWARF,__debug_ranges,regular,debug
-Ldebug_range:
-  .section  __DWARF,__debug_macinfo,regular,debug
-Ldebug_macinfo:
-Lcu_macro_begin0:
-  .byte 0                       ## End Of Macro List Mark
-  .section  __DWARF,__apple_names,regular,debug
-Lnames_begin:
-  .long 1212240712              ## Header Magic
-  .short  1                       ## Header Version
-  .short  0                       ## Header Hash Function
-  .long 1                       ## Header Bucket Count
-  .long 1                       ## Header Hash Count
-  .long 12                      ## Header Data Length
-  .long 0                       ## HeaderData Die Offset Base
-  .long 1                       ## HeaderData Atom Count
-  .short  1                       ## DW_ATOM_die_offset
-  .short  6                       ## DW_FORM_data4
-  .long -2                      ## Bucket 0 -- error: Bucket[0] has invalid hash index: [-2]
-  .long 177678                  ## Hash in Bucket 0
-  .long LNames0-Lnames_begin    ## Offset in Bucket 0
-LNames0:
-  .long 84                      ## i
-  .long 1                       ## Num DIEs
-  .long 30
-  .long 0
-  .section  __DWARF,__apple_objc,regular,debug
-Lobjc_begin:
-  .long 1212240712              ## Header Magic
-  .short  1                       ## Header Version
-  .short  0                       ## Header Hash Function
-  .long 1                       ## Header Bucket Count
-  .long 0                       ## Header Hash Count
-  .long 12                      ## Header Data Length
-  .long 0                       ## HeaderData Die Offset Base
-  .long 1                       ## HeaderData Atom Count
-  .short  1                       ## DW_ATOM_die_offset
-  .short  6                       ## DW_FORM_data4
-  .long -1                      ## Bucket 0
-  .section  __DWARF,__apple_namespac,regular,debug
-Lnamespac_begin:
-  .long 1212240712              ## Header Magic
-  .short  1                       ## Header Version
-  .short  0                       ## Header Hash Function
-  .long 1                       ## Header Bucket Count
-  .long 0                       ## Header Hash Count
-  .long 12                      ## Header Data Length
-  .long 0                       ## HeaderData Die Offset Base
-  .long 1                       ## HeaderData Atom Count
-  .short  1                       ## DW_ATOM_die_offset
-  .short  6                       ## DW_FORM_data4
-  .long -1                      ## Bucket 0
-  .section  __DWARF,__apple_types,regular,debug
-Ltypes_begin:
-  .long 1212240712              ## Header Magic
-  .short  1                       ## Header Version
-  .short  0                       ## Header Hash Function
-  .long 1                       ## Header Bucket Count
-  .long 1                       ## Header Hash Count
-  .long 20                      ## Header Data Length
-  .long 0                       ## HeaderData Die Offset Base
-  .long 3                       ## HeaderData Atom Count
-  .short  1                       ## DW_ATOM_die_offset
-  .short  6                       ## DW_FORM_data4
-  .short  3                       ## DW_ATOM_die_tag
-  .short  5                       ## DW_FORM_data2
-  .short  4                       ## DW_ATOM_type_flags
-  .short  11                      ## DW_FORM_data1
-  .long 0                       ## Bucket 0
-  .long 193495088               ## Hash in Bucket 0
-  .long Ltypes0-Ltypes_begin    ## Offset in Bucket 0
-Ltypes0:
-  .long 86                      ## int
-  .long 1                       ## Num DIEs
-  .long 51
-  .short  36
-  .byte 0
-  .long 0
-  .section  __DWARF,__apple_exttypes,regular,debug
-Lexttypes_begin:
-  .long 1212240712              ## Header Magic
-  .short  1                       ## Header Version
-  .short  0                       ## Header Hash Function
-  .long 1                       ## Header Bucket Count
-  .long 0                       ## Header Hash Count
-  .long 12                      ## Header Data Length
-  .long 0                       ## HeaderData Die Offset Base
-  .long 1                       ## HeaderData Atom Count
-  .short  7                       ## DW_ATOM_ext_types
-  .short  6                       ## DW_FORM_data4
-  .long -1                      ## Bucket 0
-
-.subsections_via_symbols
-  .section  __DWARF,__debug_line,regular,debug
-Lsection_line:
-Lline_table_start0:

test/tools/llvm-dwarfdump/X86/apple_names_verify_data.s

+# RUN: llvm-mc %s -filetype obj -triple x86_64-apple-darwin -o - \
+# RUN: | not llvm-dwarfdump -verify - \
+# RUN: | FileCheck %s
+
+# CHECK: Verifying .apple_names...
+# CHECK-NEXT: error: Bucket[0] has invalid hash index: 4294967294
+# CHECK-NEXT: error: Hash[0] has invalid HashData offset: 0x000000b4
+# CHECK-NEXT: error: .apple_names Bucket[1] Hash[1] = 0x0002b60f Str[0] = 0x0000005a DIE[0] = 0x00000001 is not a valid DIE offset for "j".
+
+# This test is meant to verify that the -verify option 
+# in llvm-dwarfdump, correctly identifies
+# an invalid hash index for bucket[0] in the .apple_names section, 
+# an invalid HashData offset for Hash[0], as well as
+# an invalid DIE offset in the .debug_info section.
+# We're reading an invalid DIE due to the incorrect interpretation of DW_FORM for the DIE.
+# Instead of DW_FORM_data4 the Atom[0].form is: DW_FORM_flag_present.
+
+  .section  __TEXT,__text,regular,pure_instructions
+  .file 1 "basic.c"
+  .comm _i,4,2                  ## @i
+  .comm _j,4,2                  ## @j
+  .section  __DWARF,__debug_str,regular,debug
+Linfo_string:
+  .asciz  "Apple LLVM version 8.1.0 (clang-802.0.35)" ## string offset=0
+  .asciz  "basic.c"               ## string offset=42
+  .asciz  "/Users/sgravani/Development/tests" ## string offset=50
+  .asciz  "i"                     ## string offset=84
+  .asciz  "int"                   ## string offset=86
+  .asciz  "j"                     ## string offset=90
+  .section  __DWARF,__debug_info,regular,debug
+Lsection_info:
+  .section  __DWARF,__apple_names,regular,debug
+Lnames_begin:
+  .long 1212240712              ## Header Magic
+  .short  1                       ## Header Version
+  .short  0                       ## Header Hash Function
+  .long 2                       ## Header Bucket Count
+  .long 2                       ## Header Hash Count
+  .long 12                      ## Header Data Length
+  .long 0                       ## HeaderData Die Offset Base
+  .long 1                       ## HeaderData Atom Count
+  .short  1                       ## DW_ATOM_die_offset
+  .short  25                       ## DW_FORM_data4 -- error: .apple_names Bucket[1] Hash[1] = 0x0002b60f Str[0] = 0x0000005a DIE[0] = 0x00000001 is not a valid DIE offset for "j".
+  .long -2                      ## Bucket 0 -- error: Bucket[0] has invalid hash index: 4294967294
+  .long 1                       ## Bucket 1
+  .long 177678                  ## Hash in Bucket 0
+  .long 177679                  ## Hash in Bucket 1
+  .long Lsection_line    ## Offset in Bucket 0 -- error: Hash[0] has invalid HashData offset: 0x000000b4
+  .long LNames1-Lnames_begin    ## Offset in Bucket 1
+LNames0:
+  .long 84                      ## i
+  .long 1                       ## Num DIEs
+  .long 30
+  .long 0
+LNames1:
+  .long 90                      ## j
+  .long 1                       ## Num DIEs
+  .long 58
+  .long 0
+
+.subsections_via_symbols
+  .section  __DWARF,__debug_line,regular,debug
+Lsection_line:
+Lline_table_start0:

test/tools/llvm-dwarfdump/X86/apple_names_verify_form.s

+# RUN: llvm-mc %s -filetype obj -triple x86_64-apple-darwin -o - \
+# RUN: | not llvm-dwarfdump -verify - \
+# RUN: | FileCheck %s
+
+# CHECK: Verifying .apple_names...
+# CHECK-NEXT: error: unsupported form; failed to read HashData at 0x00000040
+
+# This test is meant to verify that the -verify option 
+# in llvm-dwarfdump, correctly identifies that Atom[0].form is unsupported.
+# As a result, the hashdata cannot be read.
+
+  .section  __TEXT,__text,regular,pure_instructions
+  .file 1 "basic.c"
+  .comm _i,4,2                  ## @i
+  .comm _j,4,2                  ## @j
+  .section  __DWARF,__debug_str,regular,debug
+Linfo_string:
+  .asciz  "Apple LLVM version 8.1.0 (clang-802.0.35)" ## string offset=0
+  .asciz  "basic.c"               ## string offset=42
+  .asciz  "/Users/sgravani/Development/tests" ## string offset=50
+  .asciz  "i"                     ## string offset=84
+  .asciz  "int"                   ## string offset=86
+  .asciz  "j"                     ## string offset=90
+  .section  __DWARF,__debug_info,regular,debug
+Lsection_info:
+  .section  __DWARF,__apple_names,regular,debug
+Lnames_begin:
+  .long 1212240712              ## Header Magic
+  .short  1                       ## Header Version
+  .short  0                       ## Header Hash Function
+  .long 2                       ## Header Bucket Count
+  .long 2                       ## Header Hash Count
+  .long 12                      ## Header Data Length
+  .long 0                       ## HeaderData Die Offset Base
+  .long 1                       ## HeaderData Atom Count
+  .short  1                       ## DW_ATOM_die_offset
+  .short  400                     ## DW_FORM_data4 -- error: unsupported form; failed to read HashData at 0x00000040
+  .long 0                       ## Bucket 0
+  .long 1                       ## Bucket 1
+  .long 177678                  ## Hash in Bucket 0
+  .long 177679                  ## Hash in Bucket 1
+  .long LNames0-Lnames_begin    ## Offset in Bucket 0
+  .long LNames1-Lnames_begin    ## Offset in Bucket 1
+LNames0:
+  .long 84                      ## i
+  .long 1                       ## Num DIEs
+  .long 30
+  .long 0
+LNames1:
+  .long 90                      ## j
+  .long 1                       ## Num DIEs
+  .long 58
+  .long 0
+
+.subsections_via_symbols
+  .section  __DWARF,__debug_line,regular,debug
+Lsection_line:
+Lline_table_start0: