Subject: Re: [PATCH net-next v4 0/2] net: Introducing socket mark receive socket option

From: Florian Westphal <[email-masked]>
Date: Mon, 2 Mar 2015 14:29:25 +0100

Eyal Birger <[email-masked]> wrote:
> This patch set introduces a new socket option for fetching the mark
> of skbs passed to sockets as ancillary data.
> 
> A userspace program may wish to receive the mark of packets it
> receives, for example for distinguishing between different TPROXY
> diversion rules to the same userspace proxy socket.

Hmm... Whats the use case?
Even if you cannot use multiple sockets for every divert rule,
TPROXY doesn't mangle payload; applications could use sockaddrs
returned by accept, getpeername, getsockname etc.  to figure out
which original port/address the packet was sent to?