diff --git a/port.c b/port.c
index eaf77e6..4debbe1 100644
--- a/port.c
+++ b/port.c
@@ -2767,12 +2767,35 @@ enum fsm_event port_event(struct port *p, int fd_index)
 	return p->event(p, fd_index);
 }
 
+static int port_check_tmo_valid(struct port *p, int fd_index)
+{
+	struct itimerspec tms;
+
+	if (fd_index < FD_FIRST_TIMER || fd_index >= (FD_FIRST_TIMER + N_TIMER_FDS))
+		return 1;
+
+	/* return valid if we somehow end up quering non-timer fd */
+	if (timerfd_gettime(p->fda.fd[fd_index], &tms) < 0)
+		return 1;
+	/* timer was not updated, expire valid */
+	if (tms.it_value.tv_sec == 0 && tms.it_value.tv_nsec == 0)
+		return 1;
+
+	/* timer was updated by new message read from the sockets */
+	pr_notice("%s: Timer %d expired, but was already updated, ignore",
+		  p->log_name, fd_index);
+	return 0;
+}
+
 static enum fsm_event bc_event(struct port *p, int fd_index)
 {
 	enum fsm_event event = EV_NONE;
 	struct ptp_message *msg;
 	int cnt, fd = p->fda.fd[fd_index], err;
 
+	if (!port_check_tmo_valid(p, fd_index))
+		return event;
+
 	switch (fd_index) {
 	case FD_ANNOUNCE_TIMER:
 	case FD_SYNC_RX_TIMER: