From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932354AbcAXWUj (ORCPT ); Sun, 24 Jan 2016 17:20:39 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:60844 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755584AbcAXWEN (ORCPT ); Sun, 24 Jan 2016 17:04:13 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: David Vrabel , Konrad Rzeszutek Wilk , Luis Henriques Subject: [PATCH 3.16.y-ckt 075/128] xen-netback: use RING_COPY_REQUEST() throughout Date: Sun, 24 Jan 2016 22:00:30 +0000 Message-Id: <1453672883-2708-76-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1453672883-2708-1-git-send-email-luis.henriques@canonical.com> References: <1453672883-2708-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt23 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: David Vrabel commit 68a33bfd8403e4e22847165d149823a2e0e67c9c upstream. Instead of open-coding memcpy()s and directly accessing Tx and Rx requests, use the new RING_COPY_REQUEST() that ensures the local copy is correct. This is more than is strictly necessary for guest Rx requests since only the id and gref fields are used and it is harmless if the frontend modifies these. This is part of XSA155. Reviewed-by: Wei Liu Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Luis Henriques --- drivers/net/xen-netback/netback.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 70e73907db0d..0c1574212162 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -221,18 +221,18 @@ static struct xenvif_rx_meta *get_next_rx_buffer(struct xenvif_queue *queue, struct netrx_pending_operations *npo) { struct xenvif_rx_meta *meta; - struct xen_netif_rx_request *req; + struct xen_netif_rx_request req; - req = RING_GET_REQUEST(&queue->rx, queue->rx.req_cons++); + RING_COPY_REQUEST(&queue->rx, queue->rx.req_cons++, &req); meta = npo->meta + npo->meta_prod++; meta->gso_type = XEN_NETIF_GSO_TYPE_NONE; meta->gso_size = 0; meta->size = 0; - meta->id = req->id; + meta->id = req.id; npo->copy_off = 0; - npo->copy_gref = req->gref; + npo->copy_gref = req.gref; return meta; } @@ -390,7 +390,7 @@ static int xenvif_gop_skb(struct sk_buff *skb, struct xenvif *vif = netdev_priv(skb->dev); int nr_frags = skb_shinfo(skb)->nr_frags; int i; - struct xen_netif_rx_request *req; + struct xen_netif_rx_request req; struct xenvif_rx_meta *meta; unsigned char *data; int head = 1; @@ -411,15 +411,15 @@ static int xenvif_gop_skb(struct sk_buff *skb, /* Set up a GSO prefix descriptor, if necessary */ if ((1 << gso_type) & vif->gso_prefix_mask) { - req = RING_GET_REQUEST(&queue->rx, queue->rx.req_cons++); + RING_COPY_REQUEST(&queue->rx, queue->rx.req_cons++, &req); meta = npo->meta + npo->meta_prod++; meta->gso_type = gso_type; meta->gso_size = skb_shinfo(skb)->gso_size; meta->size = 0; - meta->id = req->id; + meta->id = req.id; } - req = RING_GET_REQUEST(&queue->rx, queue->rx.req_cons++); + RING_COPY_REQUEST(&queue->rx, queue->rx.req_cons++, &req); meta = npo->meta + npo->meta_prod++; if ((1 << gso_type) & vif->gso_mask) { @@ -431,9 +431,9 @@ static int xenvif_gop_skb(struct sk_buff *skb, } meta->size = 0; - meta->id = req->id; + meta->id = req.id; npo->copy_off = 0; - npo->copy_gref = req->gref; + npo->copy_gref = req.gref; data = skb->data; while (data < skb_tail_pointer(skb)) { @@ -784,7 +784,7 @@ static void xenvif_tx_err(struct xenvif_queue *queue, spin_unlock_irqrestore(&queue->response_lock, flags); if (cons == end) break; - txp = RING_GET_REQUEST(&queue->tx, cons++); + RING_COPY_REQUEST(&queue->tx, cons++, txp); } while (1); queue->tx.req_cons = cons; } @@ -851,8 +851,7 @@ static int xenvif_count_requests(struct xenvif_queue *queue, if (drop_err) txp = &dropped_tx; - memcpy(txp, RING_GET_REQUEST(&queue->tx, cons + slots), - sizeof(*txp)); + RING_COPY_REQUEST(&queue->tx, cons + slots, txp); /* If the guest submitted a frame >= 64 KiB then * first->size overflowed and following slots will @@ -1204,8 +1203,7 @@ static int xenvif_get_extras(struct xenvif_queue *queue, return -EBADR; } - memcpy(&extra, RING_GET_REQUEST(&queue->tx, cons), - sizeof(extra)); + RING_COPY_REQUEST(&queue->tx, cons, &extra); if (unlikely(!extra.type || extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) { queue->tx.req_cons = ++cons; @@ -1341,7 +1339,7 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue, idx = queue->tx.req_cons; rmb(); /* Ensure that we see the request before we copy it. */ - memcpy(&txreq, RING_GET_REQUEST(&queue->tx, idx), sizeof(txreq)); + RING_COPY_REQUEST(&queue->tx, idx, &txreq); /* Credit-based scheduling. */ if (txreq.size > queue->remaining_credit &&