commit 303b08cbf55096aba55bd08a314e0701e5c33482
Author: Miroslav Lichvar <mlichvar@redhat.com>
Date:   Mon Dec 11 14:21:25 2017 +0100

    clock: Don't forward management requests to UDS port.
    
    The UDS port is not expected to be used by PTP clocks and forwarding of
    management messages to the port can be limited to responses.
    
    This prevents ptp4l from printing error messages when a management
    request is received from a non-UDS port and the last client which used
    the UDS port is no longer listening.
    
    Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>

diff --git a/clock.c b/clock.c
index 41c8f81..6dbc45e 100644
--- a/clock.c
+++ b/clock.c
@@ -1243,6 +1243,17 @@ static int clock_do_forward_mgmt(struct clock *c,
 {
 	if (in == out || !forwarding(c, out))
 		return 0;
+
+	/* Don't forward any requests to the UDS port. */
+	if (out == c->uds_port) {
+		switch (management_action(msg)) {
+		case GET:
+		case SET:
+		case COMMAND:
+			return 0;
+		}
+	}
+
 	if (!*pre_sent) {
 		/* delay calling msg_pre_send until
 		 * actually forwarding */