[dpdk-dev] [PATCH 4/6] vhost: fix translated address not checked

[Ferruh Yigit <ferruh.yigit@intel.com>]

From: Marvin Liu <yong.liu@intel.com>

Malicious guest can construct desc with invalid address and zero buffer
length. That will request vhost to check both translated address and
translated data length. This patch will add missed address check.

CVE-2020-10725
Fixes: 75ed51697820 ("vhost: add packed ring batch dequeue")
Fixes: ef861692c398 ("vhost: add packed ring batch enqueue")
Cc: stable@dpdk.org

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 lib/librte_vhost/virtio_net.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 1fc30c6819..8504897e7a 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -1072,6 +1072,8 @@ virtio_dev_rx_batch_packed(struct virtio_net *dev,
 						  VHOST_ACCESS_RW);
 
 	vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+		if (unlikely(!desc_addrs[i]))
+			return -1;
 		if (unlikely(lens[i] != descs[avail_idx + i].len))
 			return -1;
 	}
@@ -1827,6 +1829,8 @@ vhost_reserve_avail_batch_packed(struct virtio_net *dev,
 	}
 
 	vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+		if (unlikely(!desc_addrs[i]))
+			return -1;
 		if (unlikely((lens[i] != descs[avail_idx + i].len)))
 			return -1;
 	}
-- 
2.25.2