[$] A review of file descriptor memory safety in the kernel

On July 30, Al Viro sent

a patch set to the linux-fsdevel mailing list with a
comprehensive cover letter explaining his
recent work on ensuring that the kernel's internal representation of
file descriptors are used correctly in the kernel.
File descriptors are ubiquitous; many system calls
need to handle them. Viro's review
identified a few existing bugs, and may prevent more in the future. He also had
suggestions for ways to keep uses consistent throughout the kernel.