[llvm] [llvm][ELF]Add Shdr check for getBuildID (PR #126537)

[Ruoyu Qiu via llvm-commits]

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@@ -407,7 +407,8 @@ class ELFFile {
   Elf_Note_Iterator notes_begin(const Elf_Phdr &Phdr, Error &Err) const {
     assert(Phdr.p_type == ELF::PT_NOTE && "Phdr is not of type PT_NOTE");
     ErrorAsOutParameter ErrAsOutParam(Err);
-    if (Phdr.p_offset + Phdr.p_filesz > getBufSize()) {
+    if (Phdr.p_offset + Phdr.p_filesz > getBufSize() ||
+        Phdr.p_offset + Phdr.p_filesz < Phdr.p_offset) {
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cabbaken wrote:

This serves as an overflow check, and the unit test would fail without it. Do you think I should create a separate PR to merge this check first?

https://github.com/llvm/llvm-project/pull/126537