On Sat 08-12-18 11:26:38, Amir Goldstein wrote:
> On Sun, Dec 2, 2018 at 1:38 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote:
> >
> > When setting up an fanotify listener, user may request to get fid
> > information in event instead of an open file descriptor.
> >
> > The fid obtained with event on a watched object contains the file
> > handle returned by name_to_handle_at(2) and fsid returned by statfs(2).
> >
> > When setting a mark, we need to make sure that the filesystem
> > supports encoding file handles with name_to_handle_at(2) and that
> > statfs(2) encodes a non-zero fsid.
> >
>
> Jan,
>
> On a discussion with Matthew about tests he is writing for FAN_REPORT_TID,
> the issue of permission events came up.
> Since I am not aware of any specific benefit that FAN_REPORT_TID could
> bring to users of permission events, I think the best course of action is to
> limit the use of FAN_REPORT_TID to group with priority FAN_CLASS_NOTIF.
> That would simplify tests and man page and if we ever see a use case for
> anything else, we can add that in the future.
>
> If you agree, we should add something like this to this patch:
Yeah, that's a good point. Agreed.
Honza
> --- a/fs/notify/fanotify/fanotify_user.c
> +++ b/fs/notify/fanotify/fanotify_user.c
> @@ -768,6 +768,10 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int,
> flags, unsigned int, event_f_flags)
> return -EINVAL;
> }
>
> + if ((flags & FAN_REPORT_FID) &&
> + (flags & FANOTIFY_CLASS_BITS) != FAN_CLASS_NOTIF)
> + return -EINVAL;
> +
> user = get_current_user();
> if (atomic_read(&user->fanotify_listeners) >
> FANOTIFY_DEFAULT_MAX_LISTENERS) {
> free_uid(user);
>
>
> Thanks,
> Amir.
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
