1730 DTrace should ignore type information from modules with cth_parlabel mismatches
Reviewed by: Keith Wesolowski <keith.wesolowski@joyent.com>
Reviewed by: Adam Leventhal <ahl@delphix.com>

@@ -627,10 +627,20 @@
 
                 if ((pfp = ctf_modopen(mod->mod_mp, &error)) == NULL) {
                         goto err;
                 }
 
+                /*
+                 * If the parent module does not have the label we expect,
+                 * ignore it and fail to avoid presenting non-sensical data.
+                 */
+                if (ctf_label_info(pfp, ctf_parent_label(fp),
+                    NULL) == CTF_ERR) {
+                        ctf_close(pfp);
+                        goto err;
+                }
+
                 if (ctf_import(fp, pfp) != 0) {
                         ctf_close(pfp);
                         goto err;
                 }