rx nat event connection reference

hold a conn ref for the nat ping event. don't renew if the connection
is being garbage-collected.

Change-Id: I45ebf7b8d0362e409094666f186e6b4d58cc906a
Reviewed-on: http://gerrit.openafs.org/1573
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>

diff --git a/src/rx/rx.c b/src/rx/rx.c
index 1d0d922f284aad25fd464f96bf114ec65366887b..bf879fecd521f34cce86bdf55e5233edb6f02171 100755 (executable)
--- a/src/rx/rx.c
+++ b/src/rx/rx.c
@@ -5803,10 +5803,6 @@ rxi_NatKeepAliveEvent(struct rxevent *event, void *arg1, void *dummy)
          RX_CLIENT_CONNECTION ? rx_socket : conn->service->socket);
 
 
-    MUTEX_ENTER(&conn->conn_data_lock);
-    conn->natKeepAliveEvent = NULL;
-    MUTEX_EXIT(&conn->conn_data_lock);
-
     tp = &tbuffer[sizeof(struct rx_header)];
     taddr.sin_family = AF_INET;
     taddr.sin_port = rx_PortOf(rx_PeerOf(conn));
@@ -5830,36 +5826,51 @@ rxi_NatKeepAliveEvent(struct rxevent *event, void *arg1, void *dummy)
     tmpiov[0].iov_len = 1 + sizeof(struct rx_header);
 
     osi_NetSend(socket, &taddr, tmpiov, 1, 1 + sizeof(struct rx_header), 1);
-    rxi_ScheduleNatKeepAliveEvent(conn);
+
+    MUTEX_ENTER(&conn->conn_data_lock);
+    /* Only reschedule ourselves if the connection would not be destroyed */
+    if (conn->refCount <= 1) {
+       conn->natKeepAliveEvent = NULL;
+       MUTEX_EXIT(&conn->conn_data_lock);
+       rx_DestroyConnection(conn); /* drop the reference for this */
+    } else {
+       conn->natKeepAliveEvent = NULL;
+       conn->refCount--; /* drop the reference for this */
+       rxi_ScheduleNatKeepAliveEvent(conn);
+       MUTEX_EXIT(&conn->conn_data_lock);
+    }
 }
 
 void
 rxi_ScheduleNatKeepAliveEvent(struct rx_connection *conn)
 {
-    MUTEX_ENTER(&conn->conn_data_lock);
     if (!conn->natKeepAliveEvent && conn->secondsUntilNatPing) {
        struct clock when, now;
        clock_GetTime(&now);
        when = now;
        when.sec += conn->secondsUntilNatPing;
+       conn->refCount++; /* hold a reference for this */
        conn->natKeepAliveEvent =
            rxevent_PostNow(&when, &now, rxi_NatKeepAliveEvent, conn, 0);
     }
-    MUTEX_EXIT(&conn->conn_data_lock);
 }
 
 void
 rx_SetConnSecondsUntilNatPing(struct rx_connection *conn, afs_int32 seconds)
 {
+    MUTEX_ENTER(&conn->conn_data_lock);
     conn->secondsUntilNatPing = seconds;
     if (seconds != 0)
        rxi_ScheduleNatKeepAliveEvent(conn);
+    MUTEX_EXIT(&conn->conn_data_lock);
 }
 
 void
 rxi_NatKeepAliveOn(struct rx_connection *conn)
 {
+    MUTEX_ENTER(&conn->conn_data_lock);
     rxi_ScheduleNatKeepAliveEvent(conn);
+    MUTEX_EXIT(&conn->conn_data_lock);
 }
 
 /* When a call is in progress, this routine is called occasionally to