From: Michal Kubecek <mkubecek@xxxxxxx> Date: Fri, 26 Apr 2019 11:13:03 +0200 (CEST) > One of the comments in recent review of the ethtool netlink series pointed > out that proposed ethnl_nest_start() helper which adds NLA_F_NESTED to > second argument of nla_nest_start() is not really specific to ethtool > netlink code. That is hard to argue with as closer inspection revealed that > exactly the same helper already exists in ipset code (except it's a macro > rather than an inline function). > > Another observation was that even if NLA_F_NESTED flag was introduced in > 2007, only few netlink based interfaces set it in kernel generated messages > and even many recently added APIs omit it. That is unfortunate as without > the flag, message parsers not familiar with attribute semantics cannot > recognize nested attributes and do not see message structure; this affects > e.g. wireshark dissector or mnl_nlmsg_fprintf() from libmnl. > > This is why I'm suggesting to rename existing nla_nest_start() to different > name (nla_nest_start_noflag) and reintroduce nla_nest_start() as a wrapper > adding NLA_F_NESTED flag. This is implemented in first patch which is > mostly generated by spatch. Second patch drops ipset helper macros which > lose their purpose. Third patch cleans up minor coding style issues found > by checkpatch.pl in first patch. > > We could leave nla_nest_start() untouched and simply add a wrapper adding > NLA_F_NESTED but that would probably preserve the state when even most new > code doesn't set the flag. Series applied, thank you.
