Re: [PATCH v2 2/3] fanotify: define struct members to hold response decision context
One open question I have is what should the kernel do with
'info_type' in
response it does not understand (in the future when there are possibly more
different info types). It could just skip it because this should be just
additional info for introspection (the only mandatory part is in
fanotify_response, however it could surprise userspace that passed info is
just getting ignored. To solve this we would have to somewhere report
supported info types (maybe in fanotify fdinfo in proc). I guess we'll
cross that bridge when we get to it.
Amir, what do you think?
Regardless if and how we provide a way to enumerate supported info types,
I would prefer to reject (EINVAL) unknown info types.
We can provide a command FAN_RESPONSE_TEST to write a test response with
FAN_NOFD and some extra info so the program can test if certain info
types are supported.
Thanks,
Amir.