diff options
| author | Ben Hutchings <ben@decadent.org.uk> | 2014-10-30 18:27:12 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2014-10-30 20:01:18 -0400 |
| commit | 3d0ad09412ffe00c9afa201d01effdb6023d09b4 (patch) | |
| tree | 5244d50331be01616a16bf6f122a8769a1a928d8 /drivers/net/macvtap.c | |
| parent | 39bb5e62867de82b269b07df900165029b928359 (diff) | |
drivers/net: Disable UFO through virtio
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@decadent.org.uk>
Fixes: 916e4cf46d02 ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data")
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/macvtap.c')
| -rw-r--r-- | drivers/net/macvtap.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 65e2892342bd..2aeaa61ece09 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -65,7 +65,7 @@ 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) @@ -569,6 +569,8 @@ 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; break; default: @@ -614,8 +616,6 @@ static void 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) @@ -950,9 +950,6 @@ 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 @@ -963,7 +960,7 @@ 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; @@ -1064,7 +1061,7 @@ 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(); |