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Date: Tue, 11 Apr 2017 19:31:43 +0200
From: Pablo Neira Ayuso <pablo@netfilter.org>
To: David Ahern <dsa@cumulusnetworks.com>
Cc: Johannes Berg <johannes@sipsolutions.net>,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        Jiri Benc <jbenc@redhat.com>, jiri@resnulli.us
Subject: Re: [PATCH v3 1/5] netlink: extended ACK reporting
Message-ID: <20170411173143.GA1899@salvia> (sfid-20170411_193204_496298_B238E3E4)
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On Tue, Apr 11, 2017 at 08:25:57AM -0600, David Ahern wrote:
> On 4/11/17 1:02 AM, Johannes Berg wrote:
> > On Tue, 2017-04-11 at 08:59 +0200, Pablo Neira Ayuso wrote:
> >> CAP_ACK means: trim off the payload that the netlink error message
> >> is embedding, just like ICMP error does.
> >>
> >> What is exactly your concern? If the user explicitly requests this
> >> via socket option for this socket, then we're expecting they do the
> >> right handling for what they're asking for.
> > 
> > I think David's concern was that when you want to parse the ACK in a
> > library (or application), you may not easily know if the application
> > (or library) requested capping.
> 
> exactly.

Then, the library needs to be extended to enable this handling to
modify the way it needs to handle errors, together with the
setsockopt().