From patchwork Mon Aug 5 15:34:34 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ross Lagerwall X-Patchwork-Id: 1142272 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=citrix.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 462MSr24wjz9sMr for ; Tue, 6 Aug 2019 01:41:48 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729114AbfHEPlq (ORCPT ); Mon, 5 Aug 2019 11:41:46 -0400 Received: from esa3.hc3370-68.iphmx.com ([216.71.145.155]:43047 "EHLO esa3.hc3370-68.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726559AbfHEPlp (ORCPT ); Mon, 5 Aug 2019 11:41:45 -0400 X-Greylist: delayed 426 seconds by postgrey-1.27 at vger.kernel.org; Mon, 05 Aug 2019 11:41:44 EDT Authentication-Results: esa3.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none; spf=None smtp.pra=ross.lagerwall@citrix.com; spf=Pass smtp.mailfrom=ross.lagerwall@citrix.com; spf=None smtp.helo=postmaster@mail.citrix.com Received-SPF: None (esa3.hc3370-68.iphmx.com: no sender authenticity information available from domain of ross.lagerwall@citrix.com) identity=pra; client-ip=162.221.158.21; receiver=esa3.hc3370-68.iphmx.com; envelope-from="ross.lagerwall@citrix.com"; x-sender="ross.lagerwall@citrix.com"; x-conformance=sidf_compatible Received-SPF: Pass (esa3.hc3370-68.iphmx.com: domain of ross.lagerwall@citrix.com designates 162.221.158.21 as permitted sender) identity=mailfrom; client-ip=162.221.158.21; receiver=esa3.hc3370-68.iphmx.com; envelope-from="ross.lagerwall@citrix.com"; x-sender="ross.lagerwall@citrix.com"; x-conformance=sidf_compatible; x-record-type="v=spf1"; x-record-text="v=spf1 ip4:209.167.231.154 ip4:178.63.86.133 ip4:195.66.111.40/30 ip4:85.115.9.32/28 ip4:199.102.83.4 ip4:192.28.146.160 ip4:192.28.146.107 ip4:216.52.6.88 ip4:216.52.6.188 ip4:162.221.158.21 ip4:162.221.156.83 ~all" Received-SPF: None (esa3.hc3370-68.iphmx.com: no sender authenticity information available from domain of postmaster@mail.citrix.com) identity=helo; client-ip=162.221.158.21; receiver=esa3.hc3370-68.iphmx.com; envelope-from="ross.lagerwall@citrix.com"; x-sender="postmaster@mail.citrix.com"; x-conformance=sidf_compatible IronPort-SDR: MG3ZYEtER2WNBLk7cKJNOdkkcuRS1CfcERDgx+KKeOAZ18birOSwVaDoGmN6J5wHyqDQuNDlPo 2NMP/2mVtpyvDFsDetJxnpfrW62aypu0V88gQNBuncwFTW4ERaK4LcQ5Yim3TVEPVBLsctvPNu POCTx4WHjJdznFWGZlWrdXHDb9DPv4N3W4CvLmcgUI+QW2gyVvI6JEeLWS+x7lTTyC2SXUqAP9 nQ+DN+jzSXNcFnY+rTEx8Fdt+FA34PQ0zoc7N8tZJPVjhAojTm1my0ZBmZCZd918eQxIJ1kxWk hv8= X-SBRS: 2.7 X-MesageID: 3880647 X-Ironport-Server: esa3.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.64,350,1559534400"; d="scan'208";a="3880647" From: Ross Lagerwall To: CC: , "David S. Miller" , Paul Durrant , Wei Liu , "Ross Lagerwall" Subject: [PATCH] xen/netback: Reset nr_frags before freeing skb Date: Mon, 5 Aug 2019 16:34:34 +0100 Message-ID: <20190805153434.12144-1-ross.lagerwall@citrix.com> X-Mailer: git-send-email 2.17.2 MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org At this point nr_frags has been incremented but the frag does not yet have a page assigned so freeing the skb results in a crash. Reset nr_frags before freeing the skb to prevent this. Signed-off-by: Ross Lagerwall --- drivers/net/xen-netback/netback.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index 1d9940d4e8c7..c9262ffeefe4 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -925,6 +925,7 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue, skb_shinfo(skb)->nr_frags = MAX_SKB_FRAGS; nskb = xenvif_alloc_skb(0); if (unlikely(nskb == NULL)) { + skb_shinfo(skb)->nr_frags = 0; kfree_skb(skb); xenvif_tx_err(queue, &txreq, extra_count, idx); if (net_ratelimit()) @@ -940,6 +941,7 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue, if (xenvif_set_skb_gso(queue->vif, skb, gso)) { /* Failure in xenvif_set_skb_gso is fatal. */ + skb_shinfo(skb)->nr_frags = 0; kfree_skb(skb); kfree_skb(nskb); break;