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Date: Fri, 23 Sep 2016 15:29:15 +0800
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: huawei.xie@intel.com, dev@dpdk.org, vkaplans@redhat.com, mst@redhat.com,
 stephen@networkplumber.org
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Subject: Re: [dpdk-dev] [PATCH v2] vhost: Add indirect descriptors support
	to the TX path
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On Fri, Sep 23, 2016 at 09:16:49AM +0200, Maxime Coquelin wrote:
> +		if (vq->desc[desc_indexes[i]].flags & VRING_DESC_F_INDIRECT) {
> +			if (unlikely(!(dev->features &
> +					(1ULL << VIRTIO_RING_F_INDIRECT_DESC)))) {
> +				RTE_LOG(ERR, VHOST_DATA,
> +						"Indirect desc but feature not negotiated.\n");
> +				break;
> +			}

I thought the alignment we got before was to follow linux kernel: check
nested indirect only?

> +
> +			desc = (struct vring_desc *)gpa_to_vva(dev,
> +					vq->desc[desc_indexes[i]].addr);

I think we should check the desc addr here. Otherwise we may crash here
if a malicious guest fills some bad addresses.

	--yliu