From: Johannes Berg <johan...@sipsolutions.net> Date: Mon, 17 Sep 2018 11:57:28 +0200
> From: Johannes Berg <johannes.b...@intel.com> > > In some situations some netlink attributes may be used for output > only (kernel->userspace) or may be reserved for future use. It's > then helpful to be able to prevent userspace from using them in > messages sent to the kernel, since they'd otherwise be ignored and > any future will become impossible if this happens. > > Add NLA_REJECT to the policy which does nothing but reject (with > EINVAL) validation of any messages containing this attribute. > Allow for returning a specific extended ACK error message in the > validation_data pointer. > > While at it clear up the documentation a bit - the NLA_BITFIELD32 > documentation was added to the list of len field descriptions. > > Also, use NL_SET_BAD_ATTR() in one place where it's open-coded. > > The specific case I have in mind now is a shared nested attribute > containing request/response data, and it would be pointless and > potentially confusing to have userspace include response data in > the messages that actually contain a request. > > Signed-off-by: Johannes Berg <johannes.b...@intel.com> > --- > v2: preserve behaviour of overwriting the extack message, with > either the generic or the specific one now Applied.
