[PATCH 3.4 081/107] virtio-net: drop NETIF_F_FRAGLIST

lizf
2016-03-16T08:20:45Z

From: Jason Wang <jasowang@redhat.com>

3.4.111-rc1 review patch. If anyone has any objections, please let me know.

------------------

commit 48900cb6af4282fa0fb6ff4d72a81aa3dadb5c39 upstream.

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@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Zefan Li <lizefan@huawei.com>
---
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 efb50d6..27c82ee 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1036,9 +1036,9 @@ 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
--
1.9.1