libtraceevent: Fix memory leakage in copy_filter_type

It is necessary to free the memory that we have allocated when error occurs.

Fixes: ef3072c ("tools lib traceevent: Get rid of die in add_filter_type()")
Signed-off-by: Hewenliang <hewenliang4@huawei.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tzvetomir Stoyanov <tstoyanov@vmware.com>
Link: http://lore.kernel.org/lkml/20191119014415.57210-1-hewenliang4@huawei.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/traceevent/parse-filter.c

@@ -1473,8 +1473,10 @@ static int copy_filter_type(struct tep_event_filter *filter,
 	if (strcmp(str, "TRUE") == 0 || strcmp(str, "FALSE") == 0) {
 		/* Add trivial event */
 		arg = allocate_arg();
-		if (arg == NULL)
+		if (arg == NULL) {
+			free(str);
 			return -1;
+		}
 
 		arg->type = TEP_FILTER_ARG_BOOLEAN;
 		if (strcmp(str, "TRUE") == 0)
@@ -1483,8 +1485,11 @@ static int copy_filter_type(struct tep_event_filter *filter,
 			arg->boolean.value = 0;
 
 		filter_type = add_filter_type(filter, event->id);
-		if (filter_type == NULL)
+		if (filter_type == NULL) {
+			free(str);
+			free_arg(arg);
 			return -1;
+		}
 
 		filter_type->filter = arg;