From: David Laight <David.Laight@ACULAB.COM>
To: "'Eric Dumazet'" <eric.dumazet@gmail.com>
CC: Eric Dumazet <edumazet@google.com>,
        Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>,
        Dmitry Vyukov <dvyukov@google.com>,
        "David S. Miller" <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        "James Morris" <jmorris@namei.org>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Patrick McHardy <kaber@trash.net>, netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Vlad Yasevich <vyasevich@gmail.com>,
        "Neil Horman" <nhorman@tuxdriver.com>,
        "linux-sctp@vger.kernel.org" <linux-sctp@vger.kernel.org>,
        syzkaller <syzkaller@googlegroups.com>,
        "Kostya Serebryany" <kcc@google.com>,
        Alexander Potapenko <glider@google.com>,
        "Sasha Levin" <sasha.levin@oracle.com>
Subject: RE: [PATCH net] ipv6: sctp: clone options to avoid use after free
Thread-Topic: [PATCH net] ipv6: sctp: clone options to avoid use after free
Thread-Index: AQHRMpWwjulvUpSDiUGGxL2XGNkOVJ7Cy09wgAAEwACAAAg0QA==
Date: Wed, 9 Dec 2015 16:31:49 +0000
Message-ID: <063D6719AE5E284EB5DD2968C1650D6D1CBE9B1C@AcuExch.aculab.com>
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From: Eric Dumazet [mailto:eric.dumazet@gmail.com]
> Sent: 09 December 2015 16:00
> On Wed, 2015-12-09 at 15:49 +0000, David Laight wrote:
> > > SCTP is lacking proper np->opt cloning at accept() time.
> > >
> > > TCP and DCCP use ipv6_dup_options() helper, do the same in SCTP.
> > >
> > > We might later factorize this code in a common helper to avoid
> > > future mistakes.
> >
> > I'm wondering what the real impact of this and the other recent
> > SCTP bugs/patches is on real workloads?
> > We have enough trouble getting our customers to use kernels
> > later that the 2.6.18 based RHEL5 - without having to persuade
> > them to use kernels that contain very recent fixes.
> 
> It all depends if your customers let (hostile ?) people run programs on
> the boxes.

If they require hostile programs I'm not worried.

But it isn't entirely clear from these oops reports what the
test program is actually doing.
Some of them might be valid scenarios.
Not that our code does anything clever.

	David

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