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Date: Thu, 6 May 2021 22:11:55 +0200
From: Florian Westphal <fw@strlen.de>
To: Paolo Abeni <pabeni@redhat.com>
Cc: mptcp@lists.linux.dev, Christoph Paasch <cpaasch@apple.com>,
	Florian Westphal <fw@strlen.de>
Subject: Re: [PATCH mptcp-net] mptcp: avoid OOB access in setsockopt()
Message-ID: <20210506201155.GE12364@breakpoint.cc>
References: <79b377c2cb932a86f0fd1a17f814064dd1ad7015.1620321074.git.pabeni@redhat.com>
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User-Agent: Mutt/1.10.1 (2018-07-13)

Paolo Abeni <pabeni@redhat.com> wrote:
> We can't use tcp_set_congestion_control() on an mptcp socket, as
> such function can end-up accessing a tcp-specific field -
> prior_ssthresh - causing an OOB access.

Nice find.

> To allow propagating the correct ca algo on subflow, cache the ca
> name at initialization time.

Ok, this removes the problem of setting the right icsk_ca_ops on the
mptcp socket.

Thanks for fixing this!