xnu-3248.40.184.tar.gz

[apple/xnu.git] / bsd / netinet / mp_pcb.c

diff --git a/bsd/netinet/mp_pcb.c b/bsd/netinet/mp_pcb.c
index 304c4c05ca15986d13de9c652c9ef59b3cc45e13..31ea83fd0b6a9022a2d9c451e33bdbe3945a64e1 100644 (file)
--- a/bsd/netinet/mp_pcb.c
+++ b/bsd/netinet/mp_pcb.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012-2013 Apple Inc. All rights reserved.
+ * Copyright (c) 2012-2016 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *
@@ -207,7 +207,17 @@ mp_pcballoc(struct socket *so, struct mppcbinfo *mppi)
                lck_mtx_unlock(&mppi->mppi_lock);
                mptcplog((LOG_ERR, "MPTCP Socket: Reached MPTCP socket limit."),
                    MPTCP_SOCKET_DBG, MPTCP_LOGLVL_ERR);
-               return (ENOBUFS);
+               /*
+                * This limit may be reached either because of
+                * a leak or a transient condition where
+                * MPTCP connections are not released fast
+                * enough.
+                * We return EAFNOSUPPORT here to have user
+                * space library fallback to TCP.
+                * XXX We need to revist this when we get rid
+                * of the current low limit imposed on MPTCP.
+                */
+               return (EAFNOSUPPORT);
        }
        lck_mtx_unlock(&mppi->mppi_lock);