Re: [PATCH net-next 0/3] make nla_nest_start() add NLA_F_NESTED flag

Johannes Berg
2019-04-26T12:17:53Z

On Fri, 2019-04-26 at 13:56 +0200, Michal Kubecek wrote:

> > > I suppose we should, at least the part that attribute with NLA_NESTED
> > > policy has NLA_F_NESTED flag. I'm not so sure about the opposite (i.e.
> > > that attributes with other policies do not have the flag) as when I was
> > > checking where kernel accesses nlattr::nla_type directly rather than
> > > with nla_type(), I stumbled upon an attribute NL80211_ATTR_VENDOR_DATA
> > > which has policy NLA_BINARY but is sometimes a nest, AFAICS.
> >
> > I guess anyway we can only do it for *new* things, not really for all
> > existing attributes.
>
> Right... but what I wanted to say is that if there is already (at least)
> one attribute which may or may not be a nest, depending on a context, we
> should expect there may be also new attributes like that in the future.

Yeah, but we can handle that as we see it?

I just reposted my strict validation series - maybe we can right now, as
it's not released yet, quickly add an NL_VALIDATED_NESTED_FLAG or so to
it?

Do you want to take a stab at that? I have to go now, but I could check
in the next few days.

johannes