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Message-ID: <53F1B484.4080508@redhat.com>
Date: Mon, 18 Aug 2014 10:08:36 +0200
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v7] virtio-blk: fix reference a pointer
 which might be freed
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To: zhanghailiang <zhang.zhanghailiang@huawei.com>, qemu-devel@nongnu.org
Cc: kwolf@redhat.com, mst@redhat.com, luonengjun@huawei.com, qemu-stable@nongnu.org, peter.huangpeng@huawei.com, stefanha@redhat.com

Il 18/08/2014 09:42, zhanghailiang ha scritto:
> In function virtio_blk_handle_request, it may freed memory pointed by req,
> So do not access member of req after calling this function.
> 
> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
> ---
>  hw/block/virtio-blk.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
> index c241c50..0e3925b 100644
> --- a/hw/block/virtio-blk.c
> +++ b/hw/block/virtio-blk.c
> @@ -469,8 +469,9 @@ static void virtio_blk_dma_restart_bh(void *opaque)
>      s->rq = NULL;
>  
>      while (req) {
> +        VirtIOBlockReq *next = req->next;
>          virtio_blk_handle_request(req, &mrb);
> -        req = req->next;
> +        req = next;
>      }
>  
>      virtio_submit_multiwrite(s->bs, &mrb);
> 

Cc: qemu-stable@nongnu.org