Merge branch 'tun-net'
Herbert Xu says:
====================
tun: Fix csum_start and TUN_PKT_STRIP
The first patch fixes a serious problem that breaks checksum offload
in VMs while the second patch fixes a problem that probably affects
no one.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 7302398..9dd3746 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1235,12 +1235,20 @@
struct tun_pi pi = { 0, skb->protocol };
ssize_t total = 0;
int vlan_offset = 0, copied;
+ int vlan_hlen = 0;
+ int vnet_hdr_sz = 0;
+
+ if (vlan_tx_tag_present(skb))
+ vlan_hlen = VLAN_HLEN;
+
+ if (tun->flags & TUN_VNET_HDR)
+ vnet_hdr_sz = tun->vnet_hdr_sz;
if (!(tun->flags & TUN_NO_PI)) {
if ((len -= sizeof(pi)) < 0)
return -EINVAL;
- if (len < skb->len) {
+ if (len < skb->len + vlan_hlen + vnet_hdr_sz) {
/* Packet will be striped */
pi.flags |= TUN_PKT_STRIP;
}
@@ -1250,9 +1258,9 @@
total += sizeof(pi);
}
- if (tun->flags & TUN_VNET_HDR) {
+ if (vnet_hdr_sz) {
struct virtio_net_hdr gso = { 0 }; /* no info leak */
- if ((len -= tun->vnet_hdr_sz) < 0)
+ if ((len -= vnet_hdr_sz) < 0)
return -EINVAL;
if (skb_is_gso(skb)) {
@@ -1284,7 +1292,8 @@
if (skb->ip_summed == CHECKSUM_PARTIAL) {
gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
- gso.csum_start = skb_checksum_start_offset(skb);
+ gso.csum_start = skb_checksum_start_offset(skb) +
+ vlan_hlen;
gso.csum_offset = skb->csum_offset;
} else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
gso.flags = VIRTIO_NET_HDR_F_DATA_VALID;
@@ -1293,14 +1302,13 @@
if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total,
sizeof(gso))))
return -EFAULT;
- total += tun->vnet_hdr_sz;
+ total += vnet_hdr_sz;
}
copied = total;
- total += skb->len;
- if (!vlan_tx_tag_present(skb)) {
- len = min_t(int, skb->len, len);
- } else {
+ len = min_t(int, skb->len + vlan_hlen, len);
+ total += skb->len + vlan_hlen;
+ if (vlan_hlen) {
int copy, ret;
struct {
__be16 h_vlan_proto;
@@ -1311,8 +1319,6 @@
veth.h_vlan_TCI = htons(vlan_tx_tag_get(skb));
vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto);
- len = min_t(int, skb->len + VLAN_HLEN, len);
- total += VLAN_HLEN;
copy = min_t(int, vlan_offset, len);
ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy);