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Date: Wed, 22 Jun 2011 11:04:44 +0800
From: Jason Wang <jasowang@redhat.com>
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Subject: Re: [Qemu-devel] [PATCHv2] vhost: fix double free on device stop
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: chrisw@redhat.com, qemu-devel@nongnu.org, armbru@redhat.com

On 06/22/2011 01:34 AM, Michael S. Tsirkin wrote:
> vhost dev stop failed to clear the log field.
> Typically not an issue as dev start overwrites this field,
> but if logging gets disabled before the following start,
> it doesn't so this causes a double free.
>
> Signed-off-by: Michael S. Tsirkin<mst@redhat.com>
> ---
Acked-by: Jason Wang <jasowang@redhat.com>
>   hw/vhost.c |    1 +
>   1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/hw/vhost.c b/hw/vhost.c
> index 80f771e..c3d8821 100644
> --- a/hw/vhost.c
> +++ b/hw/vhost.c
> @@ -784,5 +784,6 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev)
>
>       hdev->started = false;
>       qemu_free(hdev->log);
> +    hdev->log = NULL;
>       hdev->log_size = 0;
>   }