Re: [PATCH] netlink: fix memory leak of dump

[Florian Westphal]

Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> wrote:
> > As David pointed out, once ->start() returns 0 we set cb_running, i.e.
> > only after successful ->start() netlink core will call ->dump() again.
> > 
> > So I see no problem setting ->data to onstack cookie and then
> > duplicating it to heap via kmemdup in ->start().
> > 
> > As far as I can see netlink core offers all functionality already,
> > so we only need to switch netfilter to make use of it.
> > 
> > If you disagree please let me know, otherwise I will cook up
> > a patch along this pattern for net/netfilter/*.
> 
> Why not just call ->done from netlink_dump_start() when it fails?

Not sure thats safe for all users, we will also still need to call
it in nft_netlink_dump_start and we need to play guess game wrt
EINTR (which can mean 'dump was now started, do not send ack').