commandline: add -i arg check

src/suricata.c

@@ -1737,6 +1737,10 @@ static TmEcode ParseCommandLine(int argc, char** argv, SCInstance *suri)
             suri->run_mode = RUNMODE_PRINT_USAGE;
             return TM_ECODE_OK;
         case 'i':
+            if (optarg == NULL) {
+                SCLogError(SC_ERR_INITIALIZATION, "no option argument (optarg) for -i");
+                return TM_ECODE_FAILED;
+            }
 #ifdef HAVE_AF_PACKET
             if (ParseCommandLineAfpacket(suri, optarg) != TM_ECODE_OK) {
                 return TM_ECODE_FAILED;