[llvm] [llvm-objdump][ELF]Fix crash when reading strings from .dynstr (PR #125679)

[Ruoyu Qiu via llvm-commits]

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@@ -221,6 +221,28 @@ template <class ELFT> void ELFDumper<ELFT>::printDynamicSection() {
   std::string TagFmt = "  %-" + std::to_string(MaxLen) + "s ";
 
   outs() << "\nDynamic Section:\n";
+  typename ELFT::Xword StringTableSize{0};
+  for (const typename ELFT::Shdr &Sec : cantFail(Elf.sections())) {
+    if (Sec.sh_type == ELF::SHT_DYNSYM) {
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cabbaken wrote:

So, in conclusion, the root cause is the implementation of `getDynamicStrTab`, right?
Would it be better to fix `getDynamicStrTab` in this PR, or should it be addressed in the next one?
Also, using `SHT_DYNSYM` in `getDynamicStrTab` seems like a poor choice and should be corrected.

Should I just fix the test and replace `SHT_DYNSYM` with `SHT_DYNAMIC` here?

https://github.com/llvm/llvm-project/pull/125679