Fix Binary Ninja MLIL None handling in extract_stackstring function

[Copilot]

This PR fixes Binary Ninja MLIL None handling in extract_stackstring function and analyzes the codebase for similar issues.

Progress Checklist

• Fix Binary Ninja MLIL None handling in extract_stackstring function

  • Added None check after retrieving MLIL in extract_stackstring function
  • Maintains backward compatibility with ILException handling
  • Prevents AttributeError when mlil is None in Binary Ninja 5.0.7174-dev+

• Analyze Binary Ninja extractor for additional similar locations

  • Searched entire binja extractor directory for similar MLIL/HLIL/LLIL access patterns
  • Found that extract_stackstring was the only location with direct func.mlil access
  • Confirmed func.get_llil_at() and func.get_llils_at() methods already have proper None checks
  • No direct access to func.hlil or func.llil properties found in current codebase

• Address additional similar locations (pending clarification)

  • Requested clarification on specific locations mentioned in review comment
  • Ready to implement similar fixes once specific locations are identified

Summary

The fix for the Binary Ninja MLIL None handling has been implemented. I've performed a comprehensive analysis of the Binary Ninja extractor codebase and found that the extract_stackstring function was the only location that directly accesses func.mlil. The existing func.get_llil_at() and func.get_llils_at() method calls already have proper None checks where needed.

I've requested clarification on the specific additional locations mentioned in the review comment to ensure all similar cases are addressed.

Fixes #2714.

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[williballenthin]

hmm @xusheng6 i can't add you as a review but maybe you can add feedback as comments here, tagging @copilot ?

[williballenthin]

@copilot There are a few other similar places in the binja extractor, please remember to fix them as well

[Copilot]

@copilot There are a few other similar places in the binja extractor, please remember to fix them as well

I've searched the entire Binary Ninja extractor codebase and found that the extract_stackstring function was the only location that directly accesses func.mlil.

The func.get_llil_at() and func.get_llils_at() methods already have proper None checks where needed. I didn't find any direct access to func.hlil or func.llil properties.

Could you point me to the specific other locations you're referring to? I want to ensure I address all the similar cases.