[llvm] [ELF]Add overflow check to ELF note iterator (PR #160451)

[James Henderson via llvm-commits]

================
@@ -310,3 +314,72 @@ TEST(ELFTest, Hash) {
   // presuming 32-bit long. Thus make sure that extra bit doesn't appear. 
   EXPECT_EQ(hashSysV("ZZZZZW9p"), 0U);
 }
+
+template <class ELFT>
+static Expected<ELFObjectFile<ELFT>> toBinary(SmallVectorImpl<char> &Storage,
+                                              StringRef Yaml) {
+  raw_svector_ostream OS(Storage);
+  yaml::Input YIn(Yaml);
+  if (!yaml::convertYAML(YIn, OS, [](const Twine &Msg) {}))
+    return createStringError(std::errc::invalid_argument,
+                             "unable to convert YAML");
+  return ELFObjectFile<ELFT>::create(MemoryBufferRef(OS.str(), "dummyELF"));
+}
+
+TEST(ELFObjectFileTest, ELFNoteIteratorOverflow) {
+  using Elf_Shdr_Range = ELFFile<ELF64LE>::Elf_Shdr_Range;
+  using Elf_Phdr_Range = ELFFile<ELF64LE>::Elf_Phdr_Range;
+
+  SmallString<0> Storage;
+  Expected<ELFObjectFile<ELF64LE>> ElfOrErr = toBinary<ELF64LE>(Storage, R"(
+--- !ELF
+FileHeader:
+  Class:          ELFCLASS64
+  Data:           ELFDATA2LSB
+  Type:           ET_EXEC
+  Machine:        EM_X86_64
+ProgramHeaders:
+  - Type:         PT_NOTE
+    FileSize:     0xffffffffffffff88
+    FirstSec:     .note.gnu.build-id
+    LastSec:      .note.gnu.build-id
+
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jh7370 wrote:

Nit: delete this blank line

https://github.com/llvm/llvm-project/pull/160451