From 56de859e9967c070464a9a9f4f18d73f9447298e Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 24 Feb 2017 11:43:36 -0800 Subject: [PATCH] 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 Signed-off-by: David S. Miller --- drivers/net/vxlan.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index b7911994112a..e375560cc74e 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)