[PATCH net-next 2/7] vxlan: simplify exception handling

[Pravin B Shelar]

vxlan egress path error handling has became complicated, it
need to handle IPv4 and IPv6 tunnel cases.
Earlier patch removes vlan handling from vxlan_build_skb(), so
vxlan_build_skb does not need to free skb and we can simplify
the xmit path by having single error handling for both type of
tunnels.

Signed-off-by: Pravin B Shelar <pshe...@ovn.org>
---
 drivers/net/vxlan.c | 28 +++++++++++-----------------
 1 file changed, 11 insertions(+), 17 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 756d826..a1e707f 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1789,7 +1789,7 @@ static int vxlan_build_skb(struct sk_buff *skb, struct 
dst_entry *dst,
        return 0;
 
 out_free:
-       kfree_skb(skb);
+       dst_release(dst);
        return err;
 }
 
@@ -1927,7 +1927,6 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct 
net_device *dev,
        struct ip_tunnel_info *info;
        struct vxlan_dev *vxlan = netdev_priv(dev);
        struct sock *sk;
-       struct rtable *rt = NULL;
        const struct iphdr *old_iph;
        union vxlan_addr *dst;
        union vxlan_addr remote_ip, local_ip;
@@ -2009,6 +2008,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct 
net_device *dev,
 
        if (dst->sa.sa_family == AF_INET) {
                struct vxlan_sock *sock4 = rcu_dereference(vxlan->vn4_sock);
+               struct rtable *rt;
 
                if (!sock4)
                        goto drop;
@@ -2030,7 +2030,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct 
net_device *dev,
                        netdev_dbg(dev, "circular route to %pI4\n",
                                   &dst->sin.sin_addr.s_addr);
                        dev->stats.collisions++;
-                       goto rt_tx_error;
+                       ip_rt_put(rt);
+                       goto tx_error;
                }
 
                /* Bypass encapsulation if the destination is local */
@@ -2058,7 +2059,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct 
net_device *dev,
                err = vxlan_build_skb(skb, &rt->dst, sizeof(struct iphdr),
                                      vni, md, flags, udp_sum);
                if (err < 0)
-                       goto xmit_tx_error;
+                       goto tx_error;
 
                udp_tunnel_xmit_skb(rt, sk, skb, src->sin.sin_addr.s_addr,
                                    dst->sin.sin_addr.s_addr, tos, ttl, df,
@@ -2117,11 +2118,9 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct 
net_device *dev,
                skb_scrub_packet(skb, xnet);
                err = vxlan_build_skb(skb, ndst, sizeof(struct ipv6hdr),
                                      vni, md, flags, udp_sum);
-               if (err < 0) {
-                       dst_release(ndst);
-                       dev->stats.tx_errors++;
-                       return;
-               }
+               if (err < 0)
+                       goto tx_error;
+
                udp_tunnel6_xmit_skb(ndst, sk, skb, dev,
                                     &src->sin6.sin6_addr,
                                     &dst->sin6.sin6_addr, tos, ttl,
@@ -2133,17 +2132,12 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct 
net_device *dev,
 
 drop:
        dev->stats.tx_dropped++;
-       goto tx_free;
+       dev_kfree_skb(skb);
+       return;
 
-xmit_tx_error:
-       /* skb is already freed. */
-       skb = NULL;
-rt_tx_error:
-       ip_rt_put(rt);
 tx_error:
        dev->stats.tx_errors++;
-tx_free:
-       dev_kfree_skb(skb);
+       kfree_skb(skb);
 }
 
 /* Transmit local packets over Vxlan
-- 
1.9.1