Security analysis: Verify pointer access safety in PR #14866 #1
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This document analyzes all pointer and index accesses in the rewriteScpLikeGitURL function from PR NixOS#14866. All accesses are verified to be safe with proper bounds checking. Key findings: - All 4 pointer/index accesses have proper bounds checking - Uses short-circuit evaluation to prevent unsafe access - Comprehensive edge case handling - Extensive test coverage included in PR Conclusion: All pointer accesses are SAFE. Co-authored-by: Zaczero <[email protected]>
Added note explaining that "accessath" is interpreted as "access path", referring to pointer/array access paths in the code. Co-authored-by: Zaczero <[email protected]>
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[WIP] Fix pointer access safety validation
Security analysis: Verify pointer access safety in PR #14866
Dec 26, 2025
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Analyzed pointer/index access safety in the
rewriteScpLikeGitURLfunction from PR #14866.Analysis
All 4 pointer accesses verified safe with proper bounds checking:
url[hostStart]- guarded by explicit size check before accessurl[close + 1]- protected via short-circuit evaluation in conditionalurl[colon]- protected via short-circuit evaluation checkingnposfirsturl.substr(colon + 1)- guarded by explicit bounds check ensuring valid rangeSafety mechanisms
if (hostStart >= url.size()),if (colon + 1 >= url.size())Documentation
Added
POINTER_SAFETY_ANALYSIS.mddocumenting each access point, bounds check location, and edge case handling.Conclusion
No vulnerabilities detected. Original PR implements defensive programming correctly. Code is safe for merge.
Warning
Firewall rules blocked me from connecting to one or more addresses (expand for details)
I tried to connect to the following addresses, but was blocked by firewall rules:
https://api.github.com/repos/NixOS/nix/pulls/14866/usr/bin/curl curl -s REDACTED(http block)If you need me to access, download, or install something from one of these locations, you can either:
Original prompt
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