test_kmod: fix small memory leak on filesystem tests

The break was in the wrong place so file system tests don't work as
intended, leaking memory at each test switch.

[mcgrof@kernel.org: massaged commit subject, noted memory leak issue without the fix]
Link: http://lkml.kernel.org/r/20170802211450.27928-6-mcgrof@kernel.org
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Reported-by: David Binderman <dcb314@hotmail.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/test_kmod.c

@@ -746,11 +746,11 @@ static int trigger_config_run_type(struct kmod_test_device *test_dev,
 						      strlen(test_str));
 		break;
 	case TEST_KMOD_FS_TYPE:
-		break;
 		kfree_const(config->test_fs);
 		config->test_driver = NULL;
 		copied = config_copy_test_fs(config, test_str,
 					     strlen(test_str));
+		break;
 	default:
 		mutex_unlock(&test_dev->config_mutex);
 		return -EINVAL;