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Date: Thu, 17 Aug 2017 15:05:41 +0100
From: Stefan Hajnoczi <stefanha@redhat.com>
To: Dexuan Cui <decui@microsoft.com>
Cc: "davem@davemloft.net" <davem@davemloft.net>,
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        Dan Carpenter <dan.carpenter@oracle.com>
Subject: Re: [PATCH net-next 2/3] vsock: fix vsock_dequeue/enqueue_accept race
Message-ID: <20170817140541.GH5539@stefanha-x1.localdomain>
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On Tue, Aug 15, 2017 at 10:15:39PM +0000, Dexuan Cui wrote:
> With the current code, when vsock_dequeue_accept() is removing a sock
> from the list, nothing prevents vsock_enqueue_accept() from adding a new
> sock into the list concurrently. We should add a lock to protect the list.

The listener sock is locked, preventing concurrent modification.  I have
checked both the virtio and vmci transports.  Can you post an example
where the listener sock isn't locked?

Stefan

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