[SWSPLAT-24296] Backport ELFIO hash table bounds validation

[sstamenk]

Motivation

Backport ELFIO #174 to TheRock's pinned ELFIO 3.12.

JIRA ID: SWSPLAT-24296

Technical Details

Ports serge1/ELFIO#174 at c6e67fa to ELFIO 3.12 (on top of the existing 0001 patch). The changes:

• Validate SysV and GNU hash tables before use, and bound chain traversal, with endian-aware, alignment-safe reads.
• A miss on a well-formed table rules out the non-local symbols it covers. Local symbols, symbols outside the covered range, and unnamed symbols are still searched linearly, as are unusable tables.
• Treat a GNU bloom filter whose size is not a power of two as unusable.
• Name lookups write output parameters only on a match.
• Read symbol records with memcpy, including in arrange_local_symbols().

The public API is unchanged. Compared with the upstream PR, only the 3.12 adaptations differ: the convertor is a reference rather than a pointer, plain uint32_t is used, and doc comments follow 3.12 style.

Remove the patch when upgrading to an ELFIO release containing the upstream change.

Test Plan

• Apply the patches with TheRock's patch_third_party_source.py to a fresh elfio-3.12.tar.gz (SHA512 matching third-party/elfio).
• Build ELFIO 3.12's test suite with this patch, [SWSPLAT-24318] Backport ELFIO note bounds validation #7773's note patch, and the upstream PRs' bounds tests, using GCC ASan/UBSan.
• Look up every symbol of every symbol table in ELFIO's tests/elf_examples by name, patched vs. unpatched 3.12.

Test Result

• Patch application passed with no rejects, and the patched headers match the tested source.
• 73/73 tests pass with ASan/UBSan. On unpatched 3.12, 31 of those tests fail.
• All 10,859 example-file symbol lookups succeed (237 through hash tables), with no sanitizer reports.

Submission Checklist

• Reviewed the contributing guidelines.

Prepared with AI assistance.

🤖 Generated with Claude Code

[therock-pr-bot]

✅ All Checks Passed — Ready for Review

Check	Status	Details
📝 PR Description	✅ Pass	—
⛔ Forbidden Files	✅ Pass	—
🧪 Unit Test	✅ Pass	PR does not contain code files — Unit Test auto-passed
🔎 pre-commit	✅ Pass	—
🚫 Draft PR	🔜 To Be Enabled	—
🚩 Feature Flag	🔜 To Be Enabled	—
📊 Code Coverage	🔜 To Be Enabled	—
🤖 therock-pr-bot	✅ Pass	—

🎉 All checks passed! This PR is ready for review.

📖 Need help? See the Policy FAQ for details on every check and how to fix failures.

🙋 Wish to Override Policy?

[therock-pr-bot]

🎉 All checks passed! This PR is ready for review.