[Qemu-devel] Re: [PATCH] tun: orphan an skb on tx

[Eric Dumazet]

Le mardi 13 avril 2010 à 23:25 +0300, Michael S. Tsirkin a écrit :
> On Tue, Apr 13, 2010 at 08:31:03PM +0200, Eric Dumazet wrote:
> > Le mardi 13 avril 2010 à 20:39 +0300, Michael S. Tsirkin a écrit :
> > 
> > > > When a socket with inflight tx packets is closed, we dont block the
> > > > close, we only delay the socket freeing once all packets were delivered
> > > > and freed.
> > > > 
> > > 
> > > Which is wrong, since this is under userspace control, so you get
> > > unkillable processes.
> > > 
> > 
> > We do not get unkillable processes, at least with sockets I was thinking
> > about (TCP/UDP ones).
> > 
> > Maybe tun sockets can behave the same ?
> 
> Looks like that's what my patch does: ip_rcv seems to call
> skb_orphan too.

Well, I was speaking of tx side, you speak of receiving side.
An external flood (coming from another domain) is another problem.

A sender might flood the 'network' inside our domain. How can we
reasonably limit the sender ?

Maybe the answer is 'We can not', but it should be stated somewhere, so
that someone can address this point later.