fix(strbuf): resolve potential use-after-free and UB in ffStrbufSetNS#2265
Merged
CarterLi merged 1 commit intofastfetch-cli:devfrom Apr 9, 2026
Merged
fix(strbuf): resolve potential use-after-free and UB in ffStrbufSetNS#2265CarterLi merged 1 commit intofastfetch-cli:devfrom
CarterLi merged 1 commit intofastfetch-cli:devfrom
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Summary
This PR fixes a "Potential use after free" security alert flagged by CodeQL and addresses Undefined Behavior (UB) when setting a buffer to a substring of itself.
Related issue (required for new logos for new distros)
Fixes a CodeQL security alert (no public issue was found).
Changes
ffStrbufSetNSto allocate and copy into a new buffer before freeing the old one. This ensures that if the sourcevaluepoints into the current buffer, it remains valid during the copy even if reallocation is required.memcpywithmemmovein the non-reallocating path to safely handle cases wherevaluepoints to an overlapping memory region within the same buffer.Checklist
fastfetch-test-strbuf)