Re: [RFC/PATCH] revoke/frevoke system calls V2

On Mon, 7 Aug 2006, Edgar Toernig wrote:


Your implementation is much cruder - it simply takes the fd
away from the app; any future use gives EBADF. As a bonus,
it works for regular files and even goes as far as destroying
all mappings of the file from all processes (even root processes).
IMVHO this is a disaster from a security and reliability point
of view.


I can see the value in these system calls, but I agree that the implementation is crude. "EBADF" is not something that applications are taught to expect. Someone correct me if I'm wrong, but I can think of no situation under which a file descriptor currently gets yanked out from under your feet -- you should always have to formally abandon it with close().

This kind of thing only looks proper if it leaves the file descriptor in place and just returns errors / EOF when you attempt to access it.

Thanks,
Chase
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