The nagios plugin check_dhcp dies with a segfault on some (not all!) systems. 

Mar  5 15:20:45 lilith kernel: pid 8543 (check_dhcp), uid 0: exited on signal 11

This seems to be an off-by-one in the command line parser. Note that this cannot be reproduced by running check_dhcp directly from the command line, it only happens when run by a nagios worker. 

--- check_dhcp.c.orig   2015-03-05 15:25:55.000000000 +0000
+++ check_dhcp.c        2015-03-05 15:26:33.000000000 +0000
@@ -1185,7 +1185,7 @@
                        }
                }
 
-       return i;
+       return i+1;
         }