[PATCH 3.12 122/127] drivers/net: Disable UFO through virtio
From: Jiri Slaby
Date: Fri Nov 25 2016 - 03:35:23 EST
From: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
commit 3d0ad09412ffe00c9afa201d01effdb6023d09b4 upstream.
IPv6 does not allow fragmentation by routers, so there is no
fragmentation ID in the fixed header. UFO for IPv6 requires the ID to
be passed separately, but there is no provision for this in the virtio
net protocol.
Until recently our software implementation of UFO/IPv6 generated a new
ID, but this was a bug. Now we will use ID=0 for any UFO/IPv6 packet
passed through a tap, which is even worse.
Unfortunately there is no distinction between UFO/IPv4 and v6
features, so disable UFO on taps and virtio_net completely until we
have a proper solution.
We cannot depend on VM managers respecting the tap feature flags, so
keep accepting UFO packets but log a warning the first time we do
this.
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Fixes: 916e4cf46d02 ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data")
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/net/macvtap.c | 13 +++++--------
drivers/net/tun.c | 19 +++++++++++--------
drivers/net/virtio_net.c | 24 ++++++++++++++----------
3 files changed, 30 insertions(+), 26 deletions(-)
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index 98ce4feb9a79..576c3236fa40 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -67,7 +67,7 @@ static struct cdev macvtap_cdev;
static const struct proto_ops macvtap_socket_ops;
#define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
- NETIF_F_TSO6 | NETIF_F_UFO)
+ NETIF_F_TSO6)
#define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO)
#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG | NETIF_F_FRAGLIST)
@@ -566,6 +566,8 @@ static int macvtap_skb_from_vnet_hdr(struct sk_buff *skb,
gso_type = SKB_GSO_TCPV6;
break;
case VIRTIO_NET_HDR_GSO_UDP:
+ pr_warn_once("macvtap: %s: using disabled UFO feature; please fix this program\n",
+ current->comm);
gso_type = SKB_GSO_UDP;
if (skb->protocol == htons(ETH_P_IPV6))
ipv6_proxy_select_ident(skb);
@@ -613,8 +615,6 @@ static int macvtap_skb_to_vnet_hdr(const struct sk_buff *skb,
vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else if (sinfo->gso_type & SKB_GSO_TCPV6)
vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
- else if (sinfo->gso_type & SKB_GSO_UDP)
- vnet_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
else
BUG();
if (sinfo->gso_type & SKB_GSO_TCP_ECN)
@@ -962,9 +962,6 @@ static int set_offload(struct macvtap_queue *q, unsigned long arg)
if (arg & TUN_F_TSO6)
feature_mask |= NETIF_F_TSO6;
}
-
- if (arg & TUN_F_UFO)
- feature_mask |= NETIF_F_UFO;
}
/* tun/tap driver inverts the usage for TSO offloads, where
@@ -975,7 +972,7 @@ static int set_offload(struct macvtap_queue *q, unsigned long arg)
* When user space turns off TSO, we turn off GSO/LRO so that
* user-space will not receive TSO frames.
*/
- if (feature_mask & (NETIF_F_TSO | NETIF_F_TSO6 | NETIF_F_UFO))
+ if (feature_mask & (NETIF_F_TSO | NETIF_F_TSO6))
features |= RX_OFFLOADS;
else
features &= ~RX_OFFLOADS;
@@ -1076,7 +1073,7 @@ static long macvtap_ioctl(struct file *file, unsigned int cmd,
case TUNSETOFFLOAD:
/* let the user check for future flags */
if (arg & ~(TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6 |
- TUN_F_TSO_ECN | TUN_F_UFO))
+ TUN_F_TSO_ECN))
return -EINVAL;
rtnl_lock();
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 813750d09680..46f9cb21ec56 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -173,7 +173,7 @@ struct tun_struct {
struct net_device *dev;
netdev_features_t set_features;
#define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \
- NETIF_F_TSO6|NETIF_F_UFO)
+ NETIF_F_TSO6)
int vnet_hdr_sz;
int sndbuf;
@@ -1113,10 +1113,20 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
break;
case VIRTIO_NET_HDR_GSO_UDP:
+ {
+ static bool warned;
+
+ if (!warned) {
+ warned = true;
+ netdev_warn(tun->dev,
+ "%s: using disabled UFO feature; please fix this program\n",
+ current->comm);
+ }
skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
if (skb->protocol == htons(ETH_P_IPV6))
ipv6_proxy_select_ident(skb);
break;
+ }
default:
tun->dev->stats.rx_frame_errors++;
kfree_skb(skb);
@@ -1220,8 +1230,6 @@ static ssize_t tun_put_user(struct tun_struct *tun,
gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else if (sinfo->gso_type & SKB_GSO_TCPV6)
gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
- else if (sinfo->gso_type & SKB_GSO_UDP)
- gso.gso_type = VIRTIO_NET_HDR_GSO_UDP;
else {
pr_err("unexpected GSO type: "
"0x%x, gso_size %d, hdr_len %d\n",
@@ -1750,11 +1758,6 @@ static int set_offload(struct tun_struct *tun, unsigned long arg)
features |= NETIF_F_TSO6;
arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
}
-
- if (arg & TUN_F_UFO) {
- features |= NETIF_F_UFO;
- arg &= ~TUN_F_UFO;
- }
}
/* This gives the user a way to test for new features in future by
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 5d080516d0c5..421642af8d06 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -438,8 +438,17 @@ static void receive_buf(struct receive_queue *rq, void *buf, unsigned int len)
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
break;
case VIRTIO_NET_HDR_GSO_UDP:
+ {
+ static bool warned;
+
+ if (!warned) {
+ warned = true;
+ netdev_warn(dev,
+ "host using disabled UFO feature; please fix it\n");
+ }
skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
break;
+ }
case VIRTIO_NET_HDR_GSO_TCPV6:
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
break;
@@ -754,8 +763,6 @@ static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
- else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
- hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
else
BUG();
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
@@ -1572,7 +1579,7 @@ static int virtnet_probe(struct virtio_device *vdev)
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
+ dev->hw_features |= NETIF_F_TSO
| NETIF_F_TSO_ECN | NETIF_F_TSO6;
}
/* Individual feature bits: what can host handle? */
@@ -1582,11 +1589,9 @@ static int virtnet_probe(struct virtio_device *vdev)
dev->hw_features |= NETIF_F_TSO6;
if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
dev->hw_features |= NETIF_F_TSO_ECN;
- if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
- dev->hw_features |= NETIF_F_UFO;
if (gso)
- dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
+ dev->features |= dev->hw_features & NETIF_F_ALL_TSO;
/* (!csum && gso) case will be fixed by register_netdev() */
}
if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
@@ -1621,8 +1626,7 @@ static int virtnet_probe(struct virtio_device *vdev)
/* If we can receive ANY GSO packets, we must allocate large ones. */
if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
- virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
- virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
+ virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN))
vi->big_packets = true;
if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
@@ -1808,9 +1812,9 @@ static struct virtio_device_id id_table[] = {
static unsigned int features[] = {
VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM,
VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
- VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
+ VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_TSO6,
VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6,
- VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO,
+ VIRTIO_NET_F_GUEST_ECN,
VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ,
VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN,
VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ,
--
2.10.2