fix(ast): strip stack canary boilerplate from decompiled C output#172
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fix(ast): strip stack canary boilerplate from decompiled C output#172wizardengineer wants to merge 1 commit intomainfrom
wizardengineer wants to merge 1 commit intomainfrom
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Add is_stack_canary_operation() to FunctionBuilder that detects compiler-inserted stack protector patterns by checking: - Operations with inputs referencing __stack_chk_guard globals - CALL operations targeting __stack_chk_fail Detected operations are skipped during basic block creation, removing the canary entry load and fail call from the generated C. This is a temporary solution that handles the straightforward cases (entry guard load and fail call) by pattern-matching on global names and call targets. The exit comparison block (if guard == saved) is not fully removed because the AST structuring engine reorganizes it into an if-else before our filter can catch the individual operations. A complete solution would require value-level taint tracking — marking values derived from __stack_chk_guard and propagating that taint through copies, comparisons, and branches so the entire canary exit path can be identified and stripped. That approach is more invasive and should be discussed before implementing. Partial fix for #161 Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Add is_stack_canary_operation() to FunctionBuilder that detects compiler-inserted stack protector patterns by checking:
Detected operations are skipped during basic block creation, removing the canary entry load and fail call from the generated C.
This is a temporary solution that handles the straightforward cases (entry guard load and fail call) by pattern-matching on global names and call targets. The exit comparison block (if guard == saved) is not fully removed because the AST structuring engine reorganizes it into an if-else before our filter can catch the individual operations.
A complete solution would require value-level taint tracking — marking values derived from __stack_chk_guard and propagating that taint through copies, comparisons, and branches so the entire canary exit path can be identified and stripped. That approach is more invasive and should be discussed before implementing.
Partial fix for #161