sctp: Set source addresses on the association before adding transports

Recent commit 8da645e101a8c20c6073efda3c7cc74eec01b87f
	sctp: Get rid of an extra routing lookup when adding a transport
introduced a regression in the connection setup.  The behavior was

different between IPv4 and IPv6.  IPv4 case ended up working because the
route lookup routing returned a NULL route, which triggered another
route lookup later in the output patch that succeeded.  In the IPv6 case,
a valid route was returned for first call, but we could not find a valid
source address at the time since the source addresses were not set on the
association yet.  Thus resulted in a hung connection.

The solution is to set the source addresses on the association prior to
adding peers.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 22 insertions, 19 deletions

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 8450960df24f..7eed77a39d0d 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -1485,15 +1485,13 @@ void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned len)
  * local endpoint and the remote peer.
  */
 int sctp_assoc_set_bind_addr_from_ep(struct sctp_association *asoc,
-                                     gfp_t gfp)
+                                     sctp_scope_t scope, gfp_t gfp)
 {
-        sctp_scope_t scope;
         int flags;
 
         /* Use scoping rules to determine the subset of addresses from
          * the endpoint.
          */
-        scope = sctp_scope(&asoc->peer.active_path->ipaddr);
         flags = (PF_INET6 == asoc->base.sk->sk_family) ? SCTP_ADDR6_ALLOWED : 0;
         if (asoc->peer.ipv4_address)
                 flags |= SCTP_ADDR4_PEERSUPP;
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index c8fae1983dd1..d4df45022ffa 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -384,6 +384,11 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,
         if (!new_asoc)
                 goto nomem;
 
+        if (sctp_assoc_set_bind_addr_from_ep(new_asoc,
+                                             sctp_scope(sctp_source(chunk)),
+                                             GFP_ATOMIC) < 0)
+                goto nomem_init;
+
         /* The call, sctp_process_init(), can fail on memory allocation.  */
         if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type,
                                sctp_source(chunk),
@@ -401,9 +406,6 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,
                 len = ntohs(err_chunk->chunk_hdr->length) -
                         sizeof(sctp_chunkhdr_t);
 
-        if (sctp_assoc_set_bind_addr_from_ep(new_asoc, GFP_ATOMIC) < 0)
-                goto nomem_init;
-
         repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len);
         if (!repl)
                 goto nomem_init;
@@ -1452,6 +1454,10 @@ static sctp_disposition_t sctp_sf_do_unexpected_init(
         if (!new_asoc)
                 goto nomem;
 
+        if (sctp_assoc_set_bind_addr_from_ep(new_asoc,
+                                sctp_scope(sctp_source(chunk)), GFP_ATOMIC) < 0)
+                goto nomem;
+
         /* In the outbound INIT ACK the endpoint MUST copy its current
          * Verification Tag and Peers Verification tag into a reserved
          * place (local tie-tag and per tie-tag) within the state cookie.
@@ -1488,9 +1494,6 @@ static sctp_disposition_t sctp_sf_do_unexpected_init(
                         sizeof(sctp_chunkhdr_t);
         }
 
-        if (sctp_assoc_set_bind_addr_from_ep(new_asoc, GFP_ATOMIC) < 0)
-                goto nomem;
-
         repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len);
         if (!repl)
                 goto nomem;
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index c8d05758661d..bf705ba97231 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1080,6 +1080,13 @@ static int __sctp_connect(struct sock* sk,
                                 err = -ENOMEM;
                                 goto out_free;
                         }
+
+                        err = sctp_assoc_set_bind_addr_from_ep(asoc, scope,
+                                                              GFP_KERNEL);
+                        if (err < 0) {
+                                goto out_free;
+                        }
+
                 }
 
                 /* Prime the peer's transport structures.  */
@@ -1095,11 +1102,6 @@ static int __sctp_connect(struct sock* sk,
                 walk_size += af->sockaddr_len;
         }
 
-        err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
-        if (err < 0) {
-                goto out_free;
-        }
-
         /* In case the user of sctp_connectx() wants an association
          * id back, assign one now.
          */
@@ -1689,6 +1691,11 @@ SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
                         goto out_unlock;
                 }
                 asoc = new_asoc;
+                err = sctp_assoc_set_bind_addr_from_ep(asoc, scope, GFP_KERNEL);
+                if (err < 0) {
+                        err = -ENOMEM;
+                        goto out_free;
+                }
 
                 /* If the SCTP_INIT ancillary data is specified, set all
                  * the association init values accordingly.
@@ -1718,11 +1725,6 @@ SCTP_STATIC int sctp_sendmsg(struct kiocb *iocb, struct sock *sk,
                         err = -ENOMEM;
                         goto out_free;
                 }
-                err = sctp_assoc_set_bind_addr_from_ep(asoc, GFP_KERNEL);
-                if (err < 0) {
-                        err = -ENOMEM;
-                        goto out_free;
-                }
         }
 
         /* ASSERT: we have a valid association at this point.  */