From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Subject: Re: [PATCH net] vhost-net: fix use-after-free in vhost_net_flush
Date: Thu, 20 Jun 2013 16:47:59 +0400
Message-ID: <51C2F9FF.4090702@cogentembedded.com>
References: <20130620114813.GA17373@redhat.com>
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Cc: kvm@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	virtualization@lists.linux-foundation.org,
	"David S. Miller" <davem@davemloft.net>
To: "Michael S. Tsirkin" <mst@redhat.com>
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Hello.

On 20-06-2013 15:48, Michael S. Tsirkin wrote:

> vhost_net_ubuf_put_and_wait has a confusing name:
> it will actually also free it's argument.
> Thus since commit 1280c27f8e29acf4af2da914e80ec27c3dbd5c01

    Please also specify that commit's summary line in parens.

> vhost_net_flush tries to use the argument after passing it
> to vhost_net_ubuf_put_and_wait, this results
> in use after free.
> To fix, don't free the argument in vhost_net_ubuf_put_and_wait,
> add an new API for callers that want to free ubufs.

> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

WBR, Sergei