Intersection algorithm fixes from Dave Mills

bk: 3e5093bdvhnMAlVx2usV2WDSzItPhQ

diff --git a/ntpd/ntp_proto.c b/ntpd/ntp_proto.c
index 3271ddb3c338cf4ca42cfe2d643207e1e655d499..d893b1efdc7972abac5461addc4d1b5743c7831b 100644 (file)
--- a/ntpd/ntp_proto.c
+++ b/ntpd/ntp_proto.c
@@ -2064,6 +2064,13 @@ clock_select(void)
                j++;
        }
        nlist = j;
+       if (nlist == 0) {
+#ifdef DEBUG
+               if (debug)
+                       printf("clock_select: empty intersection interval\n");
+#endif
+               return;
+       }
        for (i = 0; i < nlist; i++) {
                peer_list[i]->status = CTL_PST_SEL_SELCAND;
 
@@ -2222,8 +2229,7 @@ clock_select(void)
                        printf("select: pps offset %.6f\n",
                            sys_offset);
 #endif
-       }
-               else {
+       } else {
                if (typesystem)
                        sys_peer = osys_peer;
                else