On Fri, Jan 18, 2019 at 03:32:08PM +0100, Florian Westphal wrote: > Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> wrote: > > > + case NFT_META_IIFKIND: > > > + if (in == NULL || in->rtnl_link_ops == NULL) > > > + goto err; > > > + strncpy((char *)dest, in->rtnl_link_ops->kind, IFNAMSIZ); > > > > It seems kind can be arbitrarily large, no limitation in its length. > > Its limited to 60 or 56 bytes it seems: > char kind[MODULE_NAME_LEN]; > > nla_strlcpy(kind, linfo[IFLA_INFO_KIND], sizeof(kind)); > > (linkinfo_to_kind_ops in rtnetlink.c). > > > Thinking... > > > > There is no other way to identify a vft device rather than this > > string? The only l3mdev that exists if vrf, right? > > There is, I suggested this more generic approach, as it would allow > to create rules that match on the kind of device used (vrf, ppp, etc.). Ah I see. > If you think its too generic, ok. I think it's fine, thanks for explaining.