Can you share some justification why it's worth extending
faccessat() with new options?
Isn't faccessat() insecure in most use cases, due to TOCTTOU
(time-of-check to time-of-use) vulnerabilities? When faccessat()
returns 0, you learn that at some point in the past, the process had
permission to access a given file, though the process may or may not
have permission at the moment. Why is that a useful thing to know?
I'm sure you're familiar with all the standard arguments why using
access() tends to represent a security vulnerability. Is there a reason
why similar arguments do not apply to faccessat()?
--
