sdig: avoid segfault when ednssubnet is given with no arg

diff --git a/pdns/sdig.cc b/pdns/sdig.cc
index bcd2bbeb0cd582a8b1fa2943beaaddf2951cc85e..61a954a5957cdc8cfadb29e039e0fa4a452f21d4 100644 (file)
--- a/pdns/sdig.cc
+++ b/pdns/sdig.cc
@@ -71,7 +71,12 @@ try
       if (strcmp(argv[i], "tcp") == 0)
         tcp=true;
       if (strcmp(argv[i], "ednssubnet") == 0) {
-        ednsnm=Netmask(argv[++i]);
+        i++;
+        if (argc == i) {
+          usage();
+          exit(EXIT_FAILURE);
+        }
+        ednsnm=Netmask(argv[i]);
       }
     }
   }