sctp: add sock_reuseport for the sock in __sctp_hash_endpoint

This is a part of sk_reuseport support for sctp. It defines a helper
sctp_bind_addrs_check() to check if the bind_addrs in two socks are
matched. It will add sock_reuseport if they are completely matched,
and return err if they are partly matched, and alloc sock_reuseport
if all socks are not matched at all.

It will work until sk_reuseport support is added in
sctp_get_port_local() in the next patch.

v1->v2:
  - use 'laddr->valid && laddr2->valid' check instead as Marcelo
    pointed in sctp_bind_addrs_check().

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 9a3b48a35e90c777669a1037882624fcbd777222..cdf2e80abc44adaa16ac4e1588eba6f84626e24a 100644 (file)
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -152,7 +152,7 @@ int sctp_primitive_RECONF(struct net *net, struct sctp_association *asoc,
  */
 int sctp_rcv(struct sk_buff *skb);
 int sctp_v4_err(struct sk_buff *skb, u32 info);
-void sctp_hash_endpoint(struct sctp_endpoint *);
+int sctp_hash_endpoint(struct sctp_endpoint *ep);
 void sctp_unhash_endpoint(struct sctp_endpoint *);
 struct sock *sctp_err_lookup(struct net *net, int family, struct sk_buff *,
                             struct sctphdr *, struct sctp_association **,

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index a11f9379047698886713a0f56a950bf93dd367b3..15d017f33a4631d3c1523026ee052dc0c5104e57 100644 (file)
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1190,6 +1190,8 @@ int sctp_bind_addr_conflict(struct sctp_bind_addr *, const union sctp_addr *,
                         struct sctp_sock *, struct sctp_sock *);
 int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
                         const union sctp_addr *addr);
+int sctp_bind_addrs_check(struct sctp_sock *sp,
+                         struct sctp_sock *sp2, int cnt2);
 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr  *bp,
                                        const union sctp_addr   *addrs,
                                        int                     addrcnt,

diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c
index ba5cba56f5747d0f15061250db8c7fcd7492248e..d8fe3e549373d92524561728f375b2ce73bf0db7 100644 (file)
--- a/net/core/sock_reuseport.c
+++ b/net/core/sock_reuseport.c
@@ -187,6 +187,7 @@ int reuseport_add_sock(struct sock *sk, struct sock *sk2, bool bind_inany)
                call_rcu(&old_reuse->rcu, reuseport_free_rcu);
        return 0;
 }
+EXPORT_SYMBOL(reuseport_add_sock);
 
 void reuseport_detach_sock(struct sock *sk)
 {

diff --git a/net/sctp/bind_addr.c b/net/sctp/bind_addr.c
index 7df3704982f547eda452cac2131afae81a5c7e9e..ebf28adba78903dde891008818f5e44cd64ac90e 100644 (file)
--- a/net/sctp/bind_addr.c
+++ b/net/sctp/bind_addr.c
@@ -337,6 +337,34 @@ int sctp_bind_addr_match(struct sctp_bind_addr *bp,
        return match;
 }
 
+int sctp_bind_addrs_check(struct sctp_sock *sp,
+                         struct sctp_sock *sp2, int cnt2)
+{
+       struct sctp_bind_addr *bp2 = &sp2->ep->base.bind_addr;
+       struct sctp_bind_addr *bp = &sp->ep->base.bind_addr;
+       struct sctp_sockaddr_entry *laddr, *laddr2;
+       bool exist = false;
+       int cnt = 0;
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+               list_for_each_entry_rcu(laddr2, &bp2->address_list, list) {
+                       if (sp->pf->af->cmp_addr(&laddr->a, &laddr2->a) &&
+                           laddr->valid && laddr2->valid) {
+                               exist = true;
+                               goto next;
+                       }
+               }
+               cnt = 0;
+               break;
+next:
+               cnt++;
+       }
+       rcu_read_unlock();
+
+       return (cnt == cnt2) ? 0 : (exist ? -EEXIST : 1);
+}
+
 /* Does the address 'addr' conflict with any addresses in
  * the bp.
  */

diff --git a/net/sctp/input.c b/net/sctp/input.c
index 00f995e377956a06910ca20caf8c59db82b2526c..d7a649d240e5cf4ccf653af08bb66e1a3dcecc8e 100644 (file)
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -724,43 +724,87 @@ discard:
 }
 
 /* Insert endpoint into the hash table.  */
-static void __sctp_hash_endpoint(struct sctp_endpoint *ep)
+static int __sctp_hash_endpoint(struct sctp_endpoint *ep)
 {
-       struct net *net = sock_net(ep->base.sk);
-       struct sctp_ep_common *epb;
+       struct sock *sk = ep->base.sk;
+       struct net *net = sock_net(sk);
        struct sctp_hashbucket *head;
+       struct sctp_ep_common *epb;
 
        epb = &ep->base;
-
        epb->hashent = sctp_ep_hashfn(net, epb->bind_addr.port);
        head = &sctp_ep_hashtable[epb->hashent];
 
+       if (sk->sk_reuseport) {
+               bool any = sctp_is_ep_boundall(sk);
+               struct sctp_ep_common *epb2;
+               struct list_head *list;
+               int cnt = 0, err = 1;
+
+               list_for_each(list, &ep->base.bind_addr.address_list)
+                       cnt++;
+
+               sctp_for_each_hentry(epb2, &head->chain) {
+                       struct sock *sk2 = epb2->sk;
+
+                       if (!net_eq(sock_net(sk2), net) || sk2 == sk ||
+                           !uid_eq(sock_i_uid(sk2), sock_i_uid(sk)) ||
+                           !sk2->sk_reuseport)
+                               continue;
+
+                       err = sctp_bind_addrs_check(sctp_sk(sk2),
+                                                   sctp_sk(sk), cnt);
+                       if (!err) {
+                               err = reuseport_add_sock(sk, sk2, any);
+                               if (err)
+                                       return err;
+                               break;
+                       } else if (err < 0) {
+                               return err;
+                       }
+               }
+
+               if (err) {
+                       err = reuseport_alloc(sk, any);
+                       if (err)
+                               return err;
+               }
+       }
+
        write_lock(&head->lock);
        hlist_add_head(&epb->node, &head->chain);
        write_unlock(&head->lock);
+       return 0;
 }
 
 /* Add an endpoint to the hash. Local BH-safe. */
-void sctp_hash_endpoint(struct sctp_endpoint *ep)
+int sctp_hash_endpoint(struct sctp_endpoint *ep)
 {
+       int err;
+
        local_bh_disable();
-       __sctp_hash_endpoint(ep);
+       err = __sctp_hash_endpoint(ep);
        local_bh_enable();
+
+       return err;
 }
 
 /* Remove endpoint from the hash table.  */
 static void __sctp_unhash_endpoint(struct sctp_endpoint *ep)
 {
-       struct net *net = sock_net(ep->base.sk);
+       struct sock *sk = ep->base.sk;
        struct sctp_hashbucket *head;
        struct sctp_ep_common *epb;
 
        epb = &ep->base;
 
-       epb->hashent = sctp_ep_hashfn(net, epb->bind_addr.port);
+       epb->hashent = sctp_ep_hashfn(sock_net(sk), epb->bind_addr.port);
 
        head = &sctp_ep_hashtable[epb->hashent];
 
+       if (rcu_access_pointer(sk->sk_reuseport_cb))
+               reuseport_detach_sock(sk);
+
        write_lock(&head->lock);
        hlist_del_init(&epb->node);
        write_unlock(&head->lock);

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 739f3e50120ddf61c508cc677b46e0239054131c..2e955f1dbe3f8f9c87a41fc4251aad743dd358f4 100644 (file)
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -7852,8 +7852,7 @@ static int sctp_listen_start(struct sock *sk, int backlog)
        }
 
        sk->sk_max_ack_backlog = backlog;
-       sctp_hash_endpoint(ep);
-       return 0;
+       return sctp_hash_endpoint(ep);
 }
 
 /*