1 files changed, 9 insertions, 5 deletions

diff --git a/sys/netinet/tcp_timer.c b/sys/netinet/tcp_timer.c
index 6a98eb75d5e5..bd5f51c5bb90 100644
--- a/sys/netinet/tcp_timer.c
+++ b/sys/netinet/tcp_timer.c
@@ -614,6 +614,7 @@ tcp_timer_rexmt(void * xtp)
 	int rexmt;
 	struct inpcb *inp;
 	struct epoch_tracker et;
+	bool isipv6;
 #ifdef TCPDEBUG
 	int ostate;
 
@@ -712,12 +713,16 @@ tcp_timer_rexmt(void * xtp)
 	 * packets and process straight to FIN. In that case we won't catch
 	 * ESTABLISHED state.
 	 */
-	if (V_tcp_pmtud_blackhole_detect && (((tp->t_state == TCPS_ESTABLISHED))
-	    || (tp->t_state == TCPS_FIN_WAIT_1))) {
 #ifdef INET6
-		int isipv6;
+	isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV6) ? true : false;
+#else
+	isipv6 = false;
 #endif
-
+	if (((V_tcp_pmtud_blackhole_detect == 1) ||
+	    (V_tcp_pmtud_blackhole_detect == 2 && !isipv6) ||
+	    (V_tcp_pmtud_blackhole_detect == 3 && isipv6)) &&
+	    ((tp->t_state == TCPS_ESTABLISHED) ||
+	    (tp->t_state == TCPS_FIN_WAIT_1))) {
 		/*
 		 * Idea here is that at each stage of mtu probe (usually, 1448
 		 * -> 1188 -> 524) should be given 2 chances to recover before
@@ -746,7 +751,6 @@ tcp_timer_rexmt(void * xtp)
 			 * in an attempt to retransmit.
 			 */
 #ifdef INET6
-			isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV6) ? 1 : 0;
 			if (isipv6 &&
 			    tp->t_maxseg > V_tcp_v6pmtud_blackhole_mss) {
 				/* Use the sysctl tuneable blackhole MSS. */