udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().

That was we can make sure the output path of ipv4/ipv6 operate on
the UDP socket rather than whatever random thing happens to be in
skb->sk.

Based upon a patch by Jiri Pirko.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>

14 files changed, 48 insertions, 28 deletions

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index b5fecb49a0c6..51baac725a48 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1672,7 +1672,8 @@ static void vxlan_build_gbp_hdr(struct vxlanhdr *vxh, u32 vxflags,
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
-static int vxlan6_xmit_skb(struct dst_entry *dst, struct sk_buff *skb,
+static int vxlan6_xmit_skb(struct dst_entry *dst, struct sock *sk,
+                           struct sk_buff *skb,
                            struct net_device *dev, struct in6_addr *saddr,
                            struct in6_addr *daddr, __u8 prio, __u8 ttl,
                            __be16 src_port, __be16 dst_port,
@@ -1748,7 +1749,7 @@ static int vxlan6_xmit_skb(struct dst_entry *dst, struct sk_buff *skb,
 
         skb_set_inner_protocol(skb, htons(ETH_P_TEB));
 
-        udp_tunnel6_xmit_skb(dst, skb, dev, saddr, daddr, prio,
+        udp_tunnel6_xmit_skb(dst, sk, skb, dev, saddr, daddr, prio,
                              ttl, src_port, dst_port,
                              !!(vxflags & VXLAN_F_UDP_ZERO_CSUM6_TX));
         return 0;
@@ -1758,7 +1759,7 @@ err:
 }
 #endif
 
-int vxlan_xmit_skb(struct rtable *rt, struct sk_buff *skb,
+int vxlan_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
                    __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
                    __be16 src_port, __be16 dst_port,
                    struct vxlan_metadata *md, bool xnet, u32 vxflags)
@@ -1827,7 +1828,7 @@ int vxlan_xmit_skb(struct rtable *rt, struct sk_buff *skb,
 
         skb_set_inner_protocol(skb, htons(ETH_P_TEB));
 
-        return udp_tunnel_xmit_skb(rt, skb, src, dst, tos,
+        return udp_tunnel_xmit_skb(rt, sk, skb, src, dst, tos,
                                    ttl, df, src_port, dst_port, xnet,
                                    !(vxflags & VXLAN_F_UDP_CSUM));
 }
@@ -1882,6 +1883,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
                            struct vxlan_rdst *rdst, bool did_rsc)
 {
         struct vxlan_dev *vxlan = netdev_priv(dev);
+        struct sock *sk = vxlan->vn_sock->sock->sk;
         struct rtable *rt = NULL;
         const struct iphdr *old_iph;
         struct flowi4 fl4;
@@ -1961,7 +1963,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
                 md.vni = htonl(vni << 8);
                 md.gbp = skb->mark;
 
-                err = vxlan_xmit_skb(rt, skb, fl4.saddr,
+                err = vxlan_xmit_skb(rt, sk, skb, fl4.saddr,
                                      dst->sin.sin_addr.s_addr, tos, ttl, df,
                                      src_port, dst_port, &md,
                                      !net_eq(vxlan->net, dev_net(vxlan->dev)),
@@ -2021,7 +2023,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
                 md.vni = htonl(vni << 8);
                 md.gbp = skb->mark;
 
-                err = vxlan6_xmit_skb(ndst, skb, dev, &fl6.saddr, &fl6.daddr,
+                err = vxlan6_xmit_skb(ndst, sk, skb, dev, &fl6.saddr, &fl6.daddr,
                                       0, ttl, src_port, dst_port, &md,
                                       !net_eq(vxlan->net, dev_net(vxlan->dev)),
                                       vxlan->flags);
diff --git a/include/net/ip6_tunnel.h b/include/net/ip6_tunnel.h
index 1668be5937e6..b8529aa1dae7 100644
--- a/include/net/ip6_tunnel.h
+++ b/include/net/ip6_tunnel.h
@@ -73,13 +73,14 @@ __u32 ip6_tnl_get_cap(struct ip6_tnl *t, const struct in6_addr *laddr,
 struct net *ip6_tnl_get_link_net(const struct net_device *dev);
 int ip6_tnl_get_iflink(const struct net_device *dev);
 
-static inline void ip6tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
+static inline void ip6tunnel_xmit(struct sock *sk, struct sk_buff *skb,
+                                  struct net_device *dev)
 {
         struct net_device_stats *stats = &dev->stats;
         int pkt_len, err;
 
         pkt_len = skb->len;
-        err = ip6_local_out(skb);
+        err = ip6_local_out_sk(sk, skb);
 
         if (net_xmit_eval(err) == 0) {
                 struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index b6ae959824ff..27470cd1d5f8 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -827,6 +827,7 @@ int ip6_input(struct sk_buff *skb);
 int ip6_mc_input(struct sk_buff *skb);
 
 int __ip6_local_out(struct sk_buff *skb);
+int ip6_local_out_sk(struct sock *sk, struct sk_buff *skb);
 int ip6_local_out(struct sk_buff *skb);
 
 /*
diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index 1a20d33d56bc..c491c1221606 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -77,13 +77,14 @@ void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
                            struct udp_tunnel_sock_cfg *sock_cfg);
 
 /* Transmit the skb using UDP encapsulation. */
-int udp_tunnel_xmit_skb(struct rtable *rt, struct sk_buff *skb,
+int udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
                         __be32 src, __be32 dst, __u8 tos, __u8 ttl,
                         __be16 df, __be16 src_port, __be16 dst_port,
                         bool xnet, bool nocheck);
 
 #if IS_ENABLED(CONFIG_IPV6)
-int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sk_buff *skb,
+int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
+                         struct sk_buff *skb,
                          struct net_device *dev, struct in6_addr *saddr,
                          struct in6_addr *daddr,
                          __u8 prio, __u8 ttl, __be16 src_port,
diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index 756e4636bad8..0082b5d33d7d 100644
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -145,7 +145,7 @@ struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
 
 void vxlan_sock_release(struct vxlan_sock *vs);
 
-int vxlan_xmit_skb(struct rtable *rt, struct sk_buff *skb,
+int vxlan_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
                    __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
                    __be16 src_port, __be16 dst_port, struct vxlan_metadata *md,
                    bool xnet, u32 vxflags);
diff --git a/net/ipv4/geneve.c b/net/ipv4/geneve.c
index e64f8e9785d1..b77f5e84c623 100644
--- a/net/ipv4/geneve.c
+++ b/net/ipv4/geneve.c
@@ -136,7 +136,7 @@ int geneve_xmit_skb(struct geneve_sock *gs, struct rtable *rt,
 
         skb_set_inner_protocol(skb, htons(ETH_P_TEB));
 
-        return udp_tunnel_xmit_skb(rt, skb, src, dst,
+        return udp_tunnel_xmit_skb(rt, gs->sock->sk, skb, src, dst,
                                    tos, ttl, df, src_port, dst_port, xnet,
                                    !csum);
 }
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 6d364ab8e14e..4c2c3ba4ba65 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -782,7 +782,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
                 return;
         }
 
-        err = iptunnel_xmit(skb->sk, rt, skb, fl4.saddr, fl4.daddr, protocol,
+        err = iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol,
                             tos, ttl, df, !net_eq(tunnel->net, dev_net(dev)));
         iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
 
diff --git a/net/ipv4/udp_tunnel.c b/net/ipv4/udp_tunnel.c
index c83b35485056..6bb98cc193c9 100644
--- a/net/ipv4/udp_tunnel.c
+++ b/net/ipv4/udp_tunnel.c
@@ -75,7 +75,7 @@ void setup_udp_tunnel_sock(struct net *net, struct socket *sock,
 }
 EXPORT_SYMBOL_GPL(setup_udp_tunnel_sock);
 
-int udp_tunnel_xmit_skb(struct rtable *rt, struct sk_buff *skb,
+int udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb,
                         __be32 src, __be32 dst, __u8 tos, __u8 ttl,
                         __be16 df, __be16 src_port, __be16 dst_port,
                         bool xnet, bool nocheck)
@@ -92,7 +92,7 @@ int udp_tunnel_xmit_skb(struct rtable *rt, struct sk_buff *skb,
 
         udp_set_csum(nocheck, skb, src, dst, skb->len);
 
-        return iptunnel_xmit(skb->sk, rt, skb, src, dst, IPPROTO_UDP,
+        return iptunnel_xmit(sk, rt, skb, src, dst, IPPROTO_UDP,
                              tos, ttl, df, xnet);
 }
 EXPORT_SYMBOL_GPL(udp_tunnel_xmit_skb);
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index f724329d7436..b5e6cc1d4a73 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -760,7 +760,7 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 
         skb_set_inner_protocol(skb, protocol);
 
-        ip6tunnel_xmit(skb, dev);
+        ip6tunnel_xmit(NULL, skb, dev);
         if (ndst)
                 ip6_tnl_dst_store(tunnel, ndst);
         return 0;
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index b6a211a150b2..5cafd92c2312 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1100,7 +1100,7 @@ static int ip6_tnl_xmit2(struct sk_buff *skb,
         ipv6h->nexthdr = proto;
         ipv6h->saddr = fl6->saddr;
         ipv6h->daddr = fl6->daddr;
-        ip6tunnel_xmit(skb, dev);
+        ip6tunnel_xmit(NULL, skb, dev);
         if (ndst)
                 ip6_tnl_dst_store(t, ndst);
         return 0;
diff --git a/net/ipv6/ip6_udp_tunnel.c b/net/ipv6/ip6_udp_tunnel.c
index 32d9b268e7d8..bba8903e871f 100644
--- a/net/ipv6/ip6_udp_tunnel.c
+++ b/net/ipv6/ip6_udp_tunnel.c
@@ -62,7 +62,8 @@ error:
 }
 EXPORT_SYMBOL_GPL(udp_sock_create6);
 
-int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sk_buff *skb,
+int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
+                         struct sk_buff *skb,
                          struct net_device *dev, struct in6_addr *saddr,
                          struct in6_addr *daddr,
                          __u8 prio, __u8 ttl, __be16 src_port,
@@ -97,7 +98,7 @@ int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sk_buff *skb,
         ip6h->daddr       = *daddr;
         ip6h->saddr       = *saddr;
 
-        ip6tunnel_xmit(skb, dev);
+        ip6tunnel_xmit(sk, skb, dev);
         return 0;
 }
 EXPORT_SYMBOL_GPL(udp_tunnel6_xmit_skb);
diff --git a/net/ipv6/output_core.c b/net/ipv6/output_core.c
index 7d1131dc29fe..85892af57364 100644
--- a/net/ipv6/output_core.c
+++ b/net/ipv6/output_core.c
@@ -136,7 +136,7 @@ int ip6_dst_hoplimit(struct dst_entry *dst)
 EXPORT_SYMBOL(ip6_dst_hoplimit);
 #endif
 
-int __ip6_local_out(struct sk_buff *skb)
+static int __ip6_local_out_sk(struct sock *sk, struct sk_buff *skb)
 {
         int len;
 
@@ -146,19 +146,30 @@ int __ip6_local_out(struct sk_buff *skb)
         ipv6_hdr(skb)->payload_len = htons(len);
         IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
 
-        return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb->sk, skb,
+        return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, sk, skb,
                        NULL, skb_dst(skb)->dev, dst_output_sk);
 }
+
+int __ip6_local_out(struct sk_buff *skb)
+{
+        return __ip6_local_out_sk(skb->sk, skb);
+}
 EXPORT_SYMBOL_GPL(__ip6_local_out);
 
-int ip6_local_out(struct sk_buff *skb)
+int ip6_local_out_sk(struct sock *sk, struct sk_buff *skb)
 {
         int err;
 
-        err = __ip6_local_out(skb);
+        err = __ip6_local_out_sk(sk, skb);
         if (likely(err == 1))
-                err = dst_output(skb);
+                err = dst_output_sk(sk, skb);
 
         return err;
 }
+EXPORT_SYMBOL_GPL(ip6_local_out_sk);
+
+int ip6_local_out(struct sk_buff *skb)
+{
+        return ip6_local_out_sk(skb->sk, skb);
+}
 EXPORT_SYMBOL_GPL(ip6_local_out);
diff --git a/net/openvswitch/vport-vxlan.c b/net/openvswitch/vport-vxlan.c
index 3277a7520e31..6d39766e7828 100644
--- a/net/openvswitch/vport-vxlan.c
+++ b/net/openvswitch/vport-vxlan.c
@@ -222,7 +222,8 @@ static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
 {
         struct net *net = ovs_dp_get_net(vport->dp);
         struct vxlan_port *vxlan_port = vxlan_vport(vport);
-        __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
+        struct sock *sk = vxlan_port->vs->sock->sk;
+        __be16 dst_port = inet_sk(sk)->inet_sport;
         const struct ovs_key_ipv4_tunnel *tun_key;
         struct vxlan_metadata md = {0};
         struct rtable *rt;
@@ -255,7 +256,7 @@ static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
         vxflags = vxlan_port->exts |
                       (tun_key->tun_flags & TUNNEL_CSUM ? VXLAN_F_UDP_CSUM : 0);
 
-        err = vxlan_xmit_skb(rt, skb, fl.saddr, tun_key->ipv4_dst,
+        err = vxlan_xmit_skb(rt, sk, skb, fl.saddr, tun_key->ipv4_dst,
                              tun_key->ipv4_tos, tun_key->ipv4_ttl, df,
                              src_port, dst_port,
                              &md, false, vxflags);
diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index ef3d7aa2854a..66deebc66aa1 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -176,7 +176,8 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
                         goto tx_error;
                 }
                 ttl = ip4_dst_hoplimit(&rt->dst);
-                err = udp_tunnel_xmit_skb(rt, clone, src->ipv4.s_addr,
+                err = udp_tunnel_xmit_skb(rt, ub->ubsock->sk, clone,
+                                          src->ipv4.s_addr,
                                           dst->ipv4.s_addr, 0, ttl, 0,
                                           src->udp_port, dst->udp_port,
                                           false, true);
@@ -197,7 +198,8 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
                 if (err)
                         goto tx_error;
                 ttl = ip6_dst_hoplimit(ndst);
-                err = udp_tunnel6_xmit_skb(ndst, clone, ndst->dev, &src->ipv6,
+                err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, clone,
+                                           ndst->dev, &src->ipv6,
                                            &dst->ipv6, 0, ttl, src->udp_port,
                                            dst->udp_port, false);
 #endif