tun: Fix csum_start with VLAN acceleration

[firefly-linux-kernel-4.4.55.git] / drivers / net / tun.c

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 7302398f0b1fff89ffe4a4e373e936c928180645..57e6bf75a6325a154cd852573de1b916a6cc29d8 100644 (file)
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1235,6 +1235,10 @@ static ssize_t tun_put_user(struct tun_struct *tun,
        struct tun_pi pi = { 0, skb->protocol };
        ssize_t total = 0;
        int vlan_offset = 0, copied;
+       int vlan_hlen = 0;
+
+       if (vlan_tx_tag_present(skb))
+               vlan_hlen = VLAN_HLEN;
 
        if (!(tun->flags & TUN_NO_PI)) {
                if ((len -= sizeof(pi)) < 0)
@@ -1284,7 +1288,8 @@ static ssize_t tun_put_user(struct tun_struct *tun,
 
                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;
@@ -1297,10 +1302,9 @@ static ssize_t tun_put_user(struct tun_struct *tun,
        }
 
        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 +1315,6 @@ static ssize_t tun_put_user(struct tun_struct *tun,
                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);