Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751278AbaK1Ibh (ORCPT ); Fri, 28 Nov 2014 03:31:37 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49647 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750993AbaK1Ibf (ORCPT ); Fri, 28 Nov 2014 03:31:35 -0500 Date: Fri, 28 Nov 2014 08:39:19 +0008 From: Jason Wang Subject: Re: [PATCH v6 25/46] virtio_net: stricter short buffer length checks To: "Michael S. Tsirkin" Cc: linux-kernel@vger.kernel.org, thuth@linux.vnet.ibm.com, rusty@au1.ibm.com, netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, dahi@linux.vnet.ibm.com, pbonzini@redhat.com, David Miller Message-Id: <1417163479.5822.5@smtp.corp.redhat.com> In-Reply-To: <1417118789-18231-26-git-send-email-mst@redhat.com> References: <1417118789-18231-1-git-send-email-mst@redhat.com> <1417118789-18231-26-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 28, 2014 at 4:09 AM, Michael S. Tsirkin wrote: > Our buffer length check is not strict enough for mergeable > buffers: buffer can still be shorter that header + address > by 2 bytes. > > Fix that up. > > Signed-off-by: Michael S. Tsirkin > Reviewed-by: Cornelia Huck > --- > drivers/net/virtio_net.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 516f2cb..098f443 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -437,7 +437,7 @@ static void receive_buf(struct virtnet_info *vi, > struct receive_queue *rq, > struct sk_buff *skb; > struct virtio_net_hdr_mrg_rxbuf *hdr; > > - if (unlikely(len < sizeof(struct virtio_net_hdr) + ETH_HLEN)) { > + if (unlikely(len < vi->hdr_len + ETH_HLEN)) { > pr_debug("%s: short packet %i\n", dev->name, len); > dev->stats.rx_length_errors++; > if (vi->mergeable_rx_bufs) { > -- > MST Reviewed-by: Jason Wang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/