TLDR
-
Opening a file is trivial for app developers but demands extreme skepticism in any code that crosses a security boundary.
Key Takeaways
-
For app developers, call the standard library and move on; the OS and runtime handle the hard parts safely.
-
For code that enforces a security boundary, “don’t trust anything” is the correct answer, not an exaggeration.
-
The same syscall carries radically different risk depending on whether a security boundary is in scope.
-
Security-boundary file handling likely involves TOCTOU races, symlink attacks, directory traversal, and permission model edge cases.
-
The framing surfaces a gap many developers miss: secure-by-default assumptions collapse the moment a trust boundary appears.
Hacker News Comment Review
-
No substantive HN discussion yet.
Original | Discuss on HN