From patchwork Fri Feb 8 15:19:00 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 219202 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from chlorine.canonical.com (chlorine.canonical.com [91.189.94.204]) by ozlabs.org (Postfix) with ESMTP id D590F2C007E for ; Sat, 9 Feb 2013 02:19:29 +1100 (EST) Received: from localhost ([127.0.0.1] helo=chlorine.canonical.com) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1U3pjR-0003zE-JY; Fri, 08 Feb 2013 15:19:19 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1U3pjL-0003xJ-QY for kernel-team@lists.ubuntu.com; Fri, 08 Feb 2013 15:19:11 +0000 Received: from bl22-241-30.dsl.telepac.pt ([2.83.241.30] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1U3pjL-0005Ke-Fy for kernel-team@lists.ubuntu.com; Fri, 08 Feb 2013 15:19:11 +0000 From: Luis Henriques To: kernel-team@lists.ubuntu.com Subject: [Quantal CVE 1/2] UBUNTU: SAUCE: xen/netback: don't leak pages on failure in xen_netbk_tx_check_gop. Date: Fri, 8 Feb 2013 15:19:00 +0000 Message-Id: <1360336743-5290-6-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1360336743-5290-1-git-send-email-luis.henriques@canonical.com> References: <1360336743-5290-1-git-send-email-luis.henriques@canonical.com> X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.13 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: kernel-team-bounces@lists.ubuntu.com Errors-To: kernel-team-bounces@lists.ubuntu.com From: Ian Campbell BugLink: http://bugs.launchpad.net/bugs/1117331 Signed-off-by: Matthew Daley Reviewed-by: Konrad Rzeszutek Wilk Acked-by: Ian Campbell Acked-by: Jan Beulich CVE-2013-0217 Signed-off-by: Stefan Bader Acked-by: Luis Henriques --- drivers/net/xen-netback/netback.c | 38 +++++++++++++------------------------ 1 file changed, 13 insertions(+), 25 deletions(-) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 8ae36cb..d0a52b9 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -146,7 +146,8 @@ void xen_netbk_remove_xenvif(struct xenvif *vif) atomic_dec(&netbk->netfront_count); } -static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx); +static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx, + u8 status); static void make_tx_response(struct xenvif *vif, struct xen_netif_tx_request *txp, s8 st); @@ -978,30 +979,20 @@ static int xen_netbk_tx_check_gop(struct xen_netbk *netbk, { struct gnttab_copy *gop = *gopp; u16 pending_idx = *((u16 *)skb->data); - struct pending_tx_info *pending_tx_info = netbk->pending_tx_info; - struct xenvif *vif = pending_tx_info[pending_idx].vif; - struct xen_netif_tx_request *txp; struct skb_shared_info *shinfo = skb_shinfo(skb); int nr_frags = shinfo->nr_frags; int i, err, start; /* Check status of header. */ err = gop->status; - if (unlikely(err)) { - pending_ring_idx_t index; - index = pending_index(netbk->pending_prod++); - txp = &pending_tx_info[pending_idx].req; - make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR); - netbk->pending_ring[index] = pending_idx; - xenvif_put(vif); - } + if (unlikely(err)) + xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_ERROR); /* Skip first skb fragment if it is on same page as header fragment. */ start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx); for (i = start; i < nr_frags; i++) { int j, newerr; - pending_ring_idx_t index; pending_idx = frag_get_pending_idx(&shinfo->frags[i]); @@ -1010,16 +1001,12 @@ static int xen_netbk_tx_check_gop(struct xen_netbk *netbk, if (likely(!newerr)) { /* Had a previous error? Invalidate this fragment. */ if (unlikely(err)) - xen_netbk_idx_release(netbk, pending_idx); + xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); continue; } /* Error on this fragment: respond to client with an error. */ - txp = &netbk->pending_tx_info[pending_idx].req; - make_tx_response(vif, txp, XEN_NETIF_RSP_ERROR); - index = pending_index(netbk->pending_prod++); - netbk->pending_ring[index] = pending_idx; - xenvif_put(vif); + xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_ERROR); /* Not the first error? Preceding frags already invalidated. */ if (err) @@ -1027,10 +1014,10 @@ static int xen_netbk_tx_check_gop(struct xen_netbk *netbk, /* First error: invalidate header and preceding fragments. */ pending_idx = *((u16 *)skb->data); - xen_netbk_idx_release(netbk, pending_idx); + xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); for (j = start; j < i; j++) { pending_idx = frag_get_pending_idx(&shinfo->frags[j]); - xen_netbk_idx_release(netbk, pending_idx); + xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); } /* Remember the error: invalidate all subsequent fragments. */ @@ -1064,7 +1051,7 @@ static void xen_netbk_fill_frags(struct xen_netbk *netbk, struct sk_buff *skb) /* Take an extra reference to offset xen_netbk_idx_release */ get_page(netbk->mmap_pages[pending_idx]); - xen_netbk_idx_release(netbk, pending_idx); + xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); } } @@ -1448,7 +1435,7 @@ static void xen_netbk_tx_submit(struct xen_netbk *netbk) txp->size -= data_len; } else { /* Schedule a response immediately. */ - xen_netbk_idx_release(netbk, pending_idx); + xen_netbk_idx_release(netbk, pending_idx, XEN_NETIF_RSP_OKAY); } if (txp->flags & XEN_NETTXF_csum_blank) @@ -1503,7 +1490,8 @@ static void xen_netbk_tx_action(struct xen_netbk *netbk) } -static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx) +static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx, + u8 status) { struct xenvif *vif; struct pending_tx_info *pending_tx_info; @@ -1517,7 +1505,7 @@ static void xen_netbk_idx_release(struct xen_netbk *netbk, u16 pending_idx) vif = pending_tx_info->vif; - make_tx_response(vif, &pending_tx_info->req, XEN_NETIF_RSP_OKAY); + make_tx_response(vif, &pending_tx_info->req, status); index = pending_index(netbk->pending_prod++); netbk->pending_ring[index] = pending_idx;