regulator: plug of_node leak in regulator_register()'s error path

By calling device_initialize() earlier and noting that kfree(NULL) is
ok, we can save a bit of code in error handling and plug of_node leak.
Fixed commit already did part of the work.

Fixes: 9177514 ("regulator: fix memory leak on error path of regulator_register()")
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/f5035b1b4d40745e66bacd571bbbb5e4644d21a1.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/core.c

@@ -5167,16 +5167,16 @@ regulator_register(const struct regulator_desc *regulator_desc,
 		ret = -ENOMEM;
 		goto rinse;
 	}
+	device_initialize(&rdev->dev);
 
 	/*
 	 * Duplicate the config so the driver could override it after
 	 * parsing init data.
 	 */
 	config = kmemdup(cfg, sizeof(*cfg), GFP_KERNEL);
 	if (config == NULL) {
-		kfree(rdev);
 		ret = -ENOMEM;
-		goto rinse;
+		goto clean;
 	}
 
 	init_data = regulator_of_get_init_data(dev, regulator_desc, config,
@@ -5188,10 +5188,8 @@ regulator_register(const struct regulator_desc *regulator_desc,
 	 * from a gpio extender or something else.
 	 */
 	if (PTR_ERR(init_data) == -EPROBE_DEFER) {
-		kfree(config);
-		kfree(rdev);
 		ret = -EPROBE_DEFER;
-		goto rinse;
+		goto clean;
 	}
 
 	/*
@@ -5244,7 +5242,6 @@ regulator_register(const struct regulator_desc *regulator_desc,
 	}
 
 	/* register with sysfs */
-	device_initialize(&rdev->dev);
 	rdev->dev.class = &regulator_class;
 	rdev->dev.parent = dev;
 	dev_set_name(&rdev->dev, "regulator.%lu",
@@ -5322,13 +5319,11 @@ regulator_register(const struct regulator_desc *regulator_desc,
 	mutex_lock(&regulator_list_mutex);
 	regulator_ena_gpio_free(rdev);
 	mutex_unlock(&regulator_list_mutex);
-	put_device(&rdev->dev);
-	rdev = NULL;
 clean:
 	if (dangling_of_gpiod)
 		gpiod_put(config->ena_gpiod);
-	kfree(rdev);
 	kfree(config);
+	put_device(&rdev->dev);
 rinse:
 	if (dangling_cfg_gpiod)
 		gpiod_put(cfg->ena_gpiod);