From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] tipc: flow control should not account for sk_rcvbuf
Date: Thu, 04 Oct 2012 12:26:00 +0200
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Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	Jon Maloy <jon.maloy@ericsson.com>,
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To: Erik Hugne <erik.hugne@ericsson.com>
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On Thu, 2012-10-04 at 11:59 +0200, Erik Hugne wrote:
> > What guarantee do we have this cannot use all kernel memory ?
> >
> > If sk->sk_rcvbuf is not an acceptable limit here, you must use a
> > different limit, but not infinity.
> >
> There is an implicit limit on how much data that can be buffered on each 
> socket, controlled by TIPC_FLOW_CONTROL_WIN.
> 
> This limit is:
> TIPC_FLOW_CONTROL_WIN * 2 * TIPC_MAX_USER_MSG_SIZE

And this limit is tested _before_ queueing to backlog if socket is owned
by the user ?

You'll have to demonstrate this in the changelog.

Again, I dont think this patch is safe, we need an explicit limit.