From 19ca9fc1445b76b60d34148f7ff837b055f5dcf3 Mon Sep 17 00:00:00 2001 From: Marcelo Leitner Date: Thu, 13 Nov 2014 14:43:08 -0200 Subject: [PATCH] vxlan: Do not reuse sockets for a different address family Currently, we only match against local port number in order to reuse socket. But if this new vxlan wants an IPv6 socket and a IPv4 one bound to that port, vxlan will reuse an IPv4 socket as IPv6 and a panic will follow. The following steps reproduce it: # ip link add vxlan6 type vxlan id 42 group 229.10.10.10 \ srcport 5000 6000 dev eth0 # ip link add vxlan7 type vxlan id 43 group ff0e::110 \ srcport 5000 6000 dev eth0 # ip link set vxlan6 up # ip link set vxlan7 up [ 4.187481] BUG: unable to handle kernel NULL pointer dereference at 0000000000000058 ... [ 4.188076] Call Trace: [ 4.188085] [] ? ipv6_sock_mc_join+0x3a/0x630 [ 4.188098] [] vxlan_igmp_join+0x66/0xd0 [vxlan] [ 4.188113] [] process_one_work+0x220/0x710 [ 4.188125] [] ? process_one_work+0x1b4/0x710 [ 4.188138] [] worker_thread+0x11b/0x3a0 [ 4.188149] [] ? process_one_work+0x710/0x710 So address family must also match in order to reuse a socket. Reported-by: Jean-Tsung Hsiao Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- drivers/net/vxlan.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index cfb892b265e8..fa9dc45b75a6 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -275,13 +275,15 @@ static inline struct vxlan_rdst *first_remote_rtnl(struct vxlan_fdb *fdb) return list_first_entry(&fdb->remotes, struct vxlan_rdst, list); } -/* Find VXLAN socket based on network namespace and UDP port */ -static struct vxlan_sock *vxlan_find_sock(struct net *net, __be16 port) +/* Find VXLAN socket based on network namespace, address family and UDP port */ +static struct vxlan_sock *vxlan_find_sock(struct net *net, + sa_family_t family, __be16 port) { struct vxlan_sock *vs; hlist_for_each_entry_rcu(vs, vs_head(net, port), hlist) { - if (inet_sk(vs->sock->sk)->inet_sport == port) + if (inet_sk(vs->sock->sk)->inet_sport == port && + inet_sk(vs->sock->sk)->sk.sk_family == family) return vs; } return NULL; @@ -300,11 +302,12 @@ static struct vxlan_dev *vxlan_vs_find_vni(struct vxlan_sock *vs, u32 id) } /* Look up VNI in a per net namespace table */ -static struct vxlan_dev *vxlan_find_vni(struct net *net, u32 id, __be16 port) +static struct vxlan_dev *vxlan_find_vni(struct net *net, u32 id, + sa_family_t family, __be16 port) { struct vxlan_sock *vs; - vs = vxlan_find_sock(net, port); + vs = vxlan_find_sock(net, family, port); if (!vs) return NULL; @@ -1773,7 +1776,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, struct vxlan_dev *dst_vxlan; ip_rt_put(rt); - dst_vxlan = vxlan_find_vni(vxlan->net, vni, dst_port); + dst_vxlan = vxlan_find_vni(vxlan->net, vni, + dst->sa.sa_family, dst_port); if (!dst_vxlan) goto tx_error; vxlan_encap_bypass(skb, vxlan, dst_vxlan); @@ -1827,7 +1831,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, struct vxlan_dev *dst_vxlan; dst_release(ndst); - dst_vxlan = vxlan_find_vni(vxlan->net, vni, dst_port); + dst_vxlan = vxlan_find_vni(vxlan->net, vni, + dst->sa.sa_family, dst_port); if (!dst_vxlan) goto tx_error; vxlan_encap_bypass(skb, vxlan, dst_vxlan); @@ -1987,13 +1992,15 @@ static int vxlan_init(struct net_device *dev) struct vxlan_dev *vxlan = netdev_priv(dev); struct vxlan_net *vn = net_generic(vxlan->net, vxlan_net_id); struct vxlan_sock *vs; + bool ipv6 = vxlan->flags & VXLAN_F_IPV6; dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); if (!dev->tstats) return -ENOMEM; spin_lock(&vn->sock_lock); - vs = vxlan_find_sock(vxlan->net, vxlan->dst_port); + vs = vxlan_find_sock(vxlan->net, ipv6 ? AF_INET6 : AF_INET, + vxlan->dst_port); if (vs) { /* If we have a socket with same port already, reuse it */ atomic_inc(&vs->refcnt); @@ -2384,6 +2391,7 @@ struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port, { struct vxlan_net *vn = net_generic(net, vxlan_net_id); struct vxlan_sock *vs; + bool ipv6 = flags & VXLAN_F_IPV6; vs = vxlan_socket_create(net, port, rcv, data, flags); if (!IS_ERR(vs)) @@ -2393,7 +2401,7 @@ struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port, return vs; spin_lock(&vn->sock_lock); - vs = vxlan_find_sock(net, port); + vs = vxlan_find_sock(net, ipv6 ? AF_INET6 : AF_INET, port); if (vs) { if (vs->rcv == rcv) atomic_inc(&vs->refcnt); @@ -2552,7 +2560,8 @@ static int vxlan_newlink(struct net *net, struct net_device *dev, nla_get_u8(data[IFLA_VXLAN_UDP_ZERO_CSUM6_RX])) vxlan->flags |= VXLAN_F_UDP_ZERO_CSUM6_RX; - if (vxlan_find_vni(net, vni, vxlan->dst_port)) { + if (vxlan_find_vni(net, vni, use_ipv6 ? AF_INET6 : AF_INET, + vxlan->dst_port)) { pr_info("duplicate VNI %u\n", vni); return -EEXIST; } -- 2.39.2