vxlan: lock RCU on TX path
There is no guarantees that callers of the TX path will hold
the RCU lock. Grab it explicitly.
Fixes: c6fcc4fc5f8b ("vxlan: avoid using stale vxlan socket.")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index b791199..e375560 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -2105,6 +2105,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
src_port = udp_flow_src_port(dev_net(dev), skb, vxlan->cfg.port_min,
vxlan->cfg.port_max, true);
+ rcu_read_lock();
if (dst->sa.sa_family == AF_INET) {
struct vxlan_sock *sock4 = rcu_dereference(vxlan->vn4_sock);
struct rtable *rt;
@@ -2127,7 +2128,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
dst_port, vni, &rt->dst,
rt->rt_flags);
if (err)
- return;
+ goto out_unlock;
} else if (info->key.tun_flags & TUNNEL_DONT_FRAGMENT) {
df = htons(IP_DF);
}
@@ -2166,7 +2167,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
dst_port, vni, ndst,
rt6i_flags);
if (err)
- return;
+ goto out_unlock;
}
tos = ip_tunnel_ecn_encap(tos, old_iph, skb);
@@ -2183,6 +2184,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
label, src_port, dst_port, !udp_sum);
#endif
}
+out_unlock:
+ rcu_read_unlock();
return;
drop:
@@ -2191,6 +2194,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
return;
tx_error:
+ rcu_read_unlock();
if (err == -ELOOP)
dev->stats.collisions++;
else if (err == -ENETUNREACH)
