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Date:   Thu, 7 Feb 2019 15:20:02 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     Jens Axboe <axboe@kernel.dk>, Jann Horn <jannh@google.com>,
        linux-aio <linux-aio@kvack.org>, linux-block@vger.kernel.org,
        Linux API <linux-api@vger.kernel.org>,
        Christoph Hellwig <hch@lst.de>, Jeff Moyer <jmoyer@redhat.com>,
        Avi Kivity <avi@scylladb.com>, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 13/18] io_uring: add file set registration
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On Thu, Feb 07, 2019 at 03:20:06PM +0100, Miklos Szeredi wrote:

> > Am I right assuming that this queue-modifying operation is accept(), removing
> > an embryo unix_sock from the queue of listener and thus hiding SCM_RIGHTS in
> > _its_ queue from scan_children()?
> 
> Hmm... How about just receiving an SCM_RIGHTS socket (which was a
> candidate) from the queue of the peeked socket?

Right, skb unlinked before unix_detach_fds().  I was actually thinking of a stream
case, where unlink is done after that...

*grumble*

The entire thing is far too brittle for my taste ;-/