From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ilya Maximets Subject: [PATCH v3 2/2] vhost: do sanity check for ring descriptor address Date: Fri, 15 Jul 2016 14:15:05 +0300 Message-ID: <1468581305-11756-3-git-send-email-i.maximets@samsung.com> References: <1463748604-27251-1-git-send-email-i.maximets@samsung.com> <1468581305-11756-1-git-send-email-i.maximets@samsung.com> Cc: Dyasly Sergey , Heetae Ahn , Jianfeng Tan , Stephen Hemminger , Thomas Monjalon , Ilya Maximets To: dev@dpdk.org, Huawei Xie , Yuanhan Liu , Rich Lane Return-path: Received: from mailout2.w1.samsung.com (mailout2.w1.samsung.com [210.118.77.12]) by dpdk.org (Postfix) with ESMTP id 738415595 for ; Fri, 15 Jul 2016 13:15:32 +0200 (CEST) Received: from eucpsbgm1.samsung.com (unknown [203.254.199.244]) by mailout2.w1.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTP id <0OAC00CF6SLU2B60@mailout2.w1.samsung.com> for dev@dpdk.org; Fri, 15 Jul 2016 12:15:30 +0100 (BST) In-reply-to: <1468581305-11756-1-git-send-email-i.maximets@samsung.com> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" In current implementation vhost will crash with segmentation fault if malicious or buggy virtio application breaks addresses of descriptors. Before commit 0823c1cb0a73 ("vhost: workaround stale vring base") this crash was reproducible even with normal DPDK application that tries to change number of virtqueues dynamically inside VM. Fix that by checking addresses of descriptors before using. Signed-off-by: Ilya Maximets --- lib/librte_vhost/vhost_rxtx.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c index a9b04df..bc00518 100644 --- a/lib/librte_vhost/vhost_rxtx.c +++ b/lib/librte_vhost/vhost_rxtx.c @@ -147,10 +147,15 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq, struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0}; desc = &vq->desc[desc_idx]; - if (unlikely(desc->len < dev->vhost_hlen)) + desc_addr = gpa_to_vva(dev, desc->addr); + /* + * Checking of 'desc_addr' placed outside of 'unlikely' macro to avoid + * performance issue with some versions of gcc (4.8.4 and 5.3.0) which + * otherwise stores offset on the stack instead of in a register. + */ + if (unlikely(desc->len < dev->vhost_hlen) || !desc_addr) return -1; - desc_addr = gpa_to_vva(dev, desc->addr); rte_prefetch0((void *)(uintptr_t)desc_addr); virtio_enqueue_offload(m, &virtio_hdr.hdr); @@ -182,7 +187,10 @@ copy_mbuf_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq, return -1; desc = &vq->desc[desc->next]; - desc_addr = gpa_to_vva(dev, desc->addr); + desc_addr = gpa_to_vva(dev, desc->addr); + if (unlikely(!desc_addr)) + return -1; + desc_offset = 0; desc_avail = desc->len; } @@ -387,10 +395,10 @@ copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct vhost_virtqueue *vq, LOG_DEBUG(VHOST_DATA, "(%d) current index %d | end index %d\n", dev->vid, cur_idx, end_idx); - if (buf_vec[vec_idx].buf_len < dev->vhost_hlen) + desc_addr = gpa_to_vva(dev, buf_vec[vec_idx].buf_addr); + if (buf_vec[vec_idx].buf_len < dev->vhost_hlen || !desc_addr) return 0; - desc_addr = gpa_to_vva(dev, buf_vec[vec_idx].buf_addr); rte_prefetch0((void *)(uintptr_t)desc_addr); virtio_hdr.num_buffers = end_idx - start_idx; @@ -425,6 +433,8 @@ copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct vhost_virtqueue *vq, vec_idx++; desc_addr = gpa_to_vva(dev, buf_vec[vec_idx].buf_addr); + if (unlikely(!desc_addr)) + return 0; /* Prefetch buffer address. */ rte_prefetch0((void *)(uintptr_t)desc_addr); @@ -688,6 +698,9 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq, return -1; desc_addr = gpa_to_vva(dev, desc->addr); + if (unlikely(!desc_addr)) + return -1; + hdr = (struct virtio_net_hdr *)((uintptr_t)desc_addr); rte_prefetch0(hdr); @@ -701,6 +714,9 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq, desc = &vq->desc[desc->next]; desc_addr = gpa_to_vva(dev, desc->addr); + if (unlikely(!desc_addr)) + return -1; + rte_prefetch0((void *)(uintptr_t)desc_addr); desc_offset = 0; @@ -737,6 +753,9 @@ copy_desc_to_mbuf(struct virtio_net *dev, struct vhost_virtqueue *vq, desc = &vq->desc[desc->next]; desc_addr = gpa_to_vva(dev, desc->addr); + if (unlikely(!desc_addr)) + return -1; + rte_prefetch0((void *)(uintptr_t)desc_addr); desc_offset = 0; -- 2.7.4