On Tue, Apr 26, 2022 at 12:07:32PM +0200, Bastien Nocera wrote: > On Tue, 2022-04-26 at 10:46 +0200, Oliver Neukum wrote: > > > > > > On 26.04.22 09:21, Greg Kroah-Hartman wrote: > > > Yes, but, it's not so simple. Many people have asked for revoke() > > > to be > > > added as a syscall like is in the BSDs, but the BSDs only allow > > > that for > > > a very small subset of file descriptor types, and doing it in a > > > generic > > > fashion seems very difficult (I tried a few years ago and gave up, > > > but > > > my knowledge of the vfs layer is minimal.) > > Well, then we should go for the minimalist approach and just > > add a hook to VFS. Multiple different ioctl()s are definitely a bad > > idea. > > An frevoke() looks much easier to do than one based on paths. > > If I understand the issue behind the proposal correctly the caller > > has opened the device. > > Doesn't look like FreeBSD at least has an frevoke() syscall anymore, it > had an FREVOKE flag, which is now a define for the O_VERIFY option > which has quite different semantics: > https://www.freebsd.org/cgi/man.cgi?sektion=2&query=open Take a look at this implementation: https://man.openbsd.org/revoke.2