From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH net V2] virtio-net: drop NETIF_F_FRAGLIST Date: Wed, 5 Aug 2015 09:33:34 +0300 Message-ID: <20150805093303-mutt-send-email-mst@redhat.com> References: <1438742044-31064-1-git-send-email-jasowang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, sergei.shtylyov@cogentembedded.com To: Jason Wang Return-path: Content-Disposition: inline In-Reply-To: <1438742044-31064-1-git-send-email-jasowang@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, Aug 05, 2015 at 10:34:04AM +0800, Jason Wang wrote: > virtio declares support for NETIF_F_FRAGLIST, but assumes > that there are at most MAX_SKB_FRAGS + 2 fragments which isn't > always true with a fraglist. > > A longer fraglist in the skb will make the call to skb_to_sgvec overflow > the sg array, leading to memory corruption. > > Drop NETIF_F_FRAGLIST so we only get what we can handle. > > Cc: Michael S. Tsirkin > Signed-off-by: Jason Wang Acked-by: Michael S. Tsirkin > --- > - Change from V1: coding style fixes. > - The patch is needed for stable. > --- > drivers/net/virtio_net.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 7fbca37..237f8e5 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -1756,9 +1756,9 @@ static int virtnet_probe(struct virtio_device *vdev) > /* Do we support "hardware" checksums? */ > if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) { > /* This opens up the world of extra features. */ > - dev->hw_features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; > + dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG; > if (csum) > - dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST; > + dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG; > > if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) { > dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO > -- > 2.1.4