Add sanity checking to wgs84_separation().

1 files changed, 8 insertions, 0 deletions

diff --git a/geoid.c b/geoid.c
index 6b6ab94b..8105a2bf 100644
--- a/geoid.c
+++ b/geoid.c
@@ -58,6 +58,14 @@ double wgs84_separation(double lat, double lon)
     ilat=(int)floor(( 90.+lat)/10);
     ilon=(int)floor((180.+lon)/10);
 	
+    /* sanity checks to prevent segfault on bad data */
+    if ( ( ilat > 90 ) || ( ilat < -90 ) ) {
+	return 0.0;
+    }
+    if ( ( ilon > 180 ) || ( ilon < -180 ) ) {
+	return 0.0;
+    }
+
     ilat1=ilat;
     ilon1=ilon;
     ilat2=(ilat < GEOID_ROW-1)? ilat+1:ilat;