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

[Ruoyu Qiu via llvm-commits]

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@@ -40,7 +40,7 @@ static StringRef getInvalidNoteELF(bool WithShdr) {
   Machine:        EM_X86_64
 ProgramHeaders:
   - Type:         PT_NOTE
-    FileSize:     0xffffffffffffffff
+    FileSize:     0xffffffffffffff88
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cabbaken wrote:

In ELF.h, we calculate `Phdr.p_offset + Phdr.p_filesz`, the associated `p_offset` is 0x78, so 0xffffffffffffff88 plus 0x78 will overflow(equal to 0).

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