From: Michael S. Tsirkin <mst@xxxxxxxxxx> Virtio-net code makes assumption about virtqueue descriptor layout (e.g. sg[0] is the header, sg[1] is the data buffer). This patch makes code not rely on the layout of descriptors. Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Signed-off-by: Amos Kong <akong@xxxxxxxxxx> --- hw/virtio-net.c | 129 ++++++++++++++++++++++++++++++++----------------------- 1 files changed, 75 insertions(+), 54 deletions(-) diff --git a/hw/virtio-net.c b/hw/virtio-net.c index 3bb01b1..af1f3a1 100644 --- a/hw/virtio-net.c +++ b/hw/virtio-net.c @@ -315,44 +315,44 @@ static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features) } static int virtio_net_handle_rx_mode(VirtIONet *n, uint8_t cmd, - VirtQueueElement *elem) + struct iovec *iov, unsigned int iov_cnt) { uint8_t on; + size_t s; - if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(on)) { - error_report("virtio-net ctrl invalid rx mode command"); - exit(1); + s = iov_to_buf(iov, iov_cnt, 0, &on, sizeof(on)); + if (s != sizeof(on)) { + return VIRTIO_NET_ERR; } - on = ldub_p(elem->out_sg[1].iov_base); - - if (cmd == VIRTIO_NET_CTRL_RX_MODE_PROMISC) + if (cmd == VIRTIO_NET_CTRL_RX_MODE_PROMISC) { n->promisc = on; - else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLMULTI) + } else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLMULTI) { n->allmulti = on; - else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLUNI) + } else if (cmd == VIRTIO_NET_CTRL_RX_MODE_ALLUNI) { n->alluni = on; - else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOMULTI) + } else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOMULTI) { n->nomulti = on; - else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOUNI) + } else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOUNI) { n->nouni = on; - else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOBCAST) + } else if (cmd == VIRTIO_NET_CTRL_RX_MODE_NOBCAST) { n->nobcast = on; - else + } else { return VIRTIO_NET_ERR; + } return VIRTIO_NET_OK; } static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd, - VirtQueueElement *elem) + struct iovec *iov, unsigned int iov_cnt) { struct virtio_net_ctrl_mac mac_data; + size_t s; - if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET || elem->out_num != 3 || - elem->out_sg[1].iov_len < sizeof(mac_data) || - elem->out_sg[2].iov_len < sizeof(mac_data)) + if (cmd != VIRTIO_NET_CTRL_MAC_TABLE_SET) { return VIRTIO_NET_ERR; + } n->mac_table.in_use = 0; n->mac_table.first_multi = 0; @@ -360,54 +360,72 @@ static int virtio_net_handle_mac(VirtIONet *n, uint8_t cmd, n->mac_table.multi_overflow = 0; memset(n->mac_table.macs, 0, MAC_TABLE_ENTRIES * ETH_ALEN); - mac_data.entries = ldl_p(elem->out_sg[1].iov_base); + s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries, + sizeof(mac_data.entries)); + mac_data.entries = ldl_p(&mac_data.entries); + if (s != sizeof(mac_data.entries)) { + return VIRTIO_NET_ERR; + } + iov_discard_front(&iov, &iov_cnt, s); - if (sizeof(mac_data.entries) + - (mac_data.entries * ETH_ALEN) > elem->out_sg[1].iov_len) + if (mac_data.entries * ETH_ALEN > iov_size(iov, iov_cnt)) { return VIRTIO_NET_ERR; + } if (mac_data.entries <= MAC_TABLE_ENTRIES) { - memcpy(n->mac_table.macs, elem->out_sg[1].iov_base + sizeof(mac_data), - mac_data.entries * ETH_ALEN); + s = iov_to_buf(iov, iov_cnt, 0, n->mac_table.macs, + mac_data.entries * ETH_ALEN); + if (s != mac_data.entries * ETH_ALEN) { + return VIRTIO_NET_ERR; + } n->mac_table.in_use += mac_data.entries; } else { n->mac_table.uni_overflow = 1; } + iov_discard_front(&iov, &iov_cnt, mac_data.entries * ETH_ALEN); + n->mac_table.first_multi = n->mac_table.in_use; - mac_data.entries = ldl_p(elem->out_sg[2].iov_base); + s = iov_to_buf(iov, iov_cnt, 0, &mac_data.entries, + sizeof(mac_data.entries)); + mac_data.entries = ldl_p(&mac_data.entries); + if (s != sizeof(mac_data.entries)) { + return VIRTIO_NET_ERR; + } + + iov_discard_front(&iov, &iov_cnt, s); - if (sizeof(mac_data.entries) + - (mac_data.entries * ETH_ALEN) > elem->out_sg[2].iov_len) + if (mac_data.entries * ETH_ALEN != iov_size(iov, iov_cnt)) { return VIRTIO_NET_ERR; + } - if (mac_data.entries) { - if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) { - memcpy(n->mac_table.macs + (n->mac_table.in_use * ETH_ALEN), - elem->out_sg[2].iov_base + sizeof(mac_data), - mac_data.entries * ETH_ALEN); - n->mac_table.in_use += mac_data.entries; - } else { - n->mac_table.multi_overflow = 1; + if (n->mac_table.in_use + mac_data.entries <= MAC_TABLE_ENTRIES) { + s = iov_to_buf(iov, iov_cnt, 0, n->mac_table.macs, + mac_data.entries * ETH_ALEN); + if (s != mac_data.entries * ETH_ALEN) { + return VIRTIO_NET_ERR; } + n->mac_table.in_use += mac_data.entries; + } else { + n->mac_table.multi_overflow = 1; } return VIRTIO_NET_OK; } static int virtio_net_handle_vlan_table(VirtIONet *n, uint8_t cmd, - VirtQueueElement *elem) + struct iovec *iov, unsigned int iov_cnt) { uint16_t vid; + size_t s; - if (elem->out_num != 2 || elem->out_sg[1].iov_len != sizeof(vid)) { - error_report("virtio-net ctrl invalid vlan command"); + s = iov_to_buf(iov, iov_cnt, 0, &vid, sizeof(vid)); + vid = lduw_p(&vid); + if (s != sizeof(vid)) { return VIRTIO_NET_ERR; } - vid = lduw_p(elem->out_sg[1].iov_base); - if (vid >= MAX_VLAN) return VIRTIO_NET_ERR; @@ -427,30 +445,33 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) struct virtio_net_ctrl_hdr ctrl; virtio_net_ctrl_ack status = VIRTIO_NET_ERR; VirtQueueElement elem; + size_t s; + struct iovec *iov; + unsigned int iov_cnt; while (virtqueue_pop(vq, &elem)) { - if ((elem.in_num < 1) || (elem.out_num < 1)) { + if (iov_size(elem.in_sg, elem.in_num) < sizeof(status) || + iov_size(elem.out_sg, elem.out_num) < sizeof(ctrl)) { error_report("virtio-net ctrl missing headers"); exit(1); } - if (elem.out_sg[0].iov_len < sizeof(ctrl) || - elem.in_sg[elem.in_num - 1].iov_len < sizeof(status)) { - error_report("virtio-net ctrl header not in correct element"); - exit(1); + iov = elem.out_sg; + iov_cnt = elem.out_num; + s = iov_to_buf(iov, iov_cnt, 0, &ctrl, sizeof(ctrl)); + iov_discard_front(&iov, &iov_cnt, sizeof(ctrl)); + if (s != sizeof(ctrl)) { + status = VIRTIO_NET_ERR; + } else if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE) { + status = virtio_net_handle_rx_mode(n, ctrl.cmd, iov, iov_cnt); + } else if (ctrl.class == VIRTIO_NET_CTRL_MAC) { + status = virtio_net_handle_mac(n, ctrl.cmd, iov, iov_cnt); + } else if (ctrl.class == VIRTIO_NET_CTRL_VLAN) { + status = virtio_net_handle_vlan_table(n, ctrl.cmd, iov, iov_cnt); } - ctrl.class = ldub_p(elem.out_sg[0].iov_base); - ctrl.cmd = ldub_p(elem.out_sg[0].iov_base + sizeof(ctrl.class)); - - if (ctrl.class == VIRTIO_NET_CTRL_RX_MODE) - status = virtio_net_handle_rx_mode(n, ctrl.cmd, &elem); - else if (ctrl.class == VIRTIO_NET_CTRL_MAC) - status = virtio_net_handle_mac(n, ctrl.cmd, &elem); - else if (ctrl.class == VIRTIO_NET_CTRL_VLAN) - status = virtio_net_handle_vlan_table(n, ctrl.cmd, &elem); - - stb_p(elem.in_sg[elem.in_num - 1].iov_base, status); + s = iov_from_buf(elem.in_sg, elem.in_num, 0, &status, sizeof(status)); + assert(s == sizeof(status)); virtqueue_push(vq, &elem, sizeof(status)); virtio_notify(vdev, vq); -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html