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Date:   Thu, 26 Jul 2018 11:48:49 +0200
From:   Dominique Martinet <asmadeus@codewreck.org>
To:     Dmitry Vyukov <dvyukov@google.com>
Cc:     Tomas Bortoli <tomasbortoli@gmail.com>,
        David Miller <davem@davemloft.net>,
        v9fs-developer@lists.sourceforge.net,
        netdev <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        syzkaller <syzkaller@googlegroups.com>
Subject: Re: [PATCH] 9p: fix NULL pointer dereferences
Message-ID: <20180726094849.GA18334@nautica>
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Dmitry Vyukov wrote on Thu, Jul 26, 2018:
> > Let's refuse that at much higher level, like v9fs_mount() in
> > fs/9p/vfs_super.c
> >
> > I can't think of any valid reason for dev_name to be NULL, it's the
> > target IP or virtio handle.
> 
> But I think trans=fd allows NULL addr today, no?

Ah, right, I read the patch too fast and read unix_create as fd_create,
I never realized there was a unix_create variant...

fd legitimately doesn't need a name, you are correct.

I'm really curious if anyone ever uses the unix/fd variants for "real"
stuff though! (not meaning syzbot isn't real, but I have yet to see
anything take advantage of this, even if I could imagine some fun
applications by piping the wmii libixp server socket.. and just crashed
my laptop trying because of the (fixed) trans put bug.. I have yet to
see anyone actually doing this)


On the other hand, virtio, rdma and xen all have the same problem, so
Thomas, please fix them instead :)

-- 
Dominique Martinet