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From:   Xin Long <lucien.xin@gmail.com>
Date:   Fri, 22 Oct 2021 14:32:52 +0800
Message-ID: <CADvbK_eHsAjih9bAiH3d2cwkaizuYnn6gL85V6LdpWUrenMAxg@mail.gmail.com>
Subject: Re: [PATCH] sctp: initialize endpoint LSM labels also on the client side
To:     Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc:     Ondrej Mosnacek <omosnace@redhat.com>,
        Vlad Yasevich <vyasevich@gmail.com>,
        Neil Horman <nhorman@tuxdriver.com>,
        "linux-sctp @ vger . kernel . org" <linux-sctp@vger.kernel.org>,
        network dev <netdev@vger.kernel.org>, selinux@vger.kernel.org,
        LSM List <linux-security-module@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Richard Haines <richard_c_haines@btinternet.com>
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On Thu, Oct 21, 2021 at 11:55 PM Marcelo Ricardo Leitner
<marcelo.leitner@gmail.com> wrote:
>
> On Thu, Oct 21, 2021 at 05:38:46PM +0200, Ondrej Mosnacek wrote:
> > The secid* fields in struct sctp_endpoint are used to initialize the
> > labels of a peeloff socket created from the given association. Currently
> > they are initialized properly when a new association is created on the
> > server side (upon receiving an INIT packet), but not on the client side.
>
> +Cc Xin
Thanks Marcelo,

security_sctp_assoc_request() is not supposed to call on the client side,
as we can see on TCP. The client side's labels should be set to the
connection by selinux_inet_conn_request(). But we can't do it based
on the current hooks.

The root problem is that the current hooks incorrectly treat sctp_endpoint
in SCTP as request_sock in TCP, while it should've been sctp_association.
We need a bigger change on the current security sctp code.

I will post the patch series in hand, please take a look.