res_pjsip_sdp_rtp,sorcery: Fix invalid access and memory leak respectively.

Valgrind found a memory leak and invalid access.

* Fix invalid access by sscanf() being fed a non-nul terminated string of
digits in res/res_pjsip_sdp_rtp.c:get_codecs().

* Fix memory leak in main/sorcery.c:sorcery_object_field_destructor().

* Fix potential NULL pointer dereference in
main/xmldoc.c:xmldoc_get_syntax_config_option().

Review: https://reviewboard.asterisk.org/r/4513/
........

Merged revisions 433199 from http://svn.asterisk.org/svn/asterisk/branches/13


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@433200 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/sorcery.c

@@ -1078,6 +1078,7 @@ static void sorcery_object_field_destructor(void *obj)
 
 	if (object_field->name_regex) {
 		regfree(object_field->name_regex);
+		ast_free(object_field->name_regex);
 	}
 }
 

main/xmldoc.c

@@ -1239,7 +1239,7 @@ static char *xmldoc_get_syntax_config_option(struct ast_xml_node *fixnode, const
 	regex = ast_xml_get_attribute(fixnode, "regex");
 	ast_str_set(&syntax, 0, "%s = [%s] (Default: %s) (Regex: %s)\n",
 		name,
-		type,
+		type ?: "",
 		default_value ?: "n/a",
 		regex ?: "False");
 

res/res_pjsip_sdp_rtp.c

@@ -180,7 +180,11 @@ static void get_codecs(struct ast_sip_session *session, const struct pjmedia_sdp
 		}
 
 		if ((pjmedia_sdp_attr_get_fmtp(attr, &fmtp)) == PJ_SUCCESS) {
-			sscanf(pj_strbuf(&fmtp.fmt), "%d", &num);
+			ast_copy_pj_str(fmt_param, &fmtp.fmt, sizeof(fmt_param));
+			if (sscanf(fmt_param, "%30d", &num) != 1) {
+				continue;
+			}
+
 			if ((format = ast_rtp_codecs_get_payload_format(codecs, num))) {
 				struct ast_format *format_parsed;