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 <mst at redhat.com>
Signed-off-by: Jason Wang <jasowang at redhat.com>
---
- 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
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 <mst at redhat.com> > Signed-off-by: Jason Wang <jasowang at redhat.com>Acked-by: Michael S. Tsirkin <mst at redhat.com>> --- > - 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
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 <mst at redhat.com> > Signed-off-by: Jason Wang <jasowang at redhat.com>I noticed only now that this didn't Cc Dave, so of course it's not applied. I'm preparing a pull request anyway, so I'll merge this through my tree, and add Cc stable. Dave - ok with you?> --- > - 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
From: "Michael S. Tsirkin" <mst at redhat.com> Date: Thu, 6 Aug 2015 16:13:11 +0300> 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 <mst at redhat.com> >> Signed-off-by: Jason Wang <jasowang at redhat.com> > > I noticed only now that this didn't Cc Dave, so of course it's > not applied.CC:'ing me isn't the requirement. CC:'ing netdev is, which he did. If you check patchwork, it's there in the queue. I'm just behind and heavily backlogged because I've been working on other things.
From: Jason Wang <jasowang at redhat.com> Date: Wed, 5 Aug 2015 10:34:04 +0800> 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 <mst at redhat.com> > Signed-off-by: Jason Wang <jasowang at redhat.com>Applied, thanks Jason.