UPSTREAM: binder: free memory on error

On binder_init() the devices string is duplicated and smashed into individual
device names which are passed along. However, the original duplicated string
wasn't freed in case binder_init() failed. Let's free it on error.

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 22eb9476b5d80a393ac0ba235c42bccc90b82c76)

Change-Id: I78fdeecf70c31ba4248b3de17130f97546288f84
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 3d49fd1..e85ba20 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -5796,7 +5796,7 @@
 static int __init binder_init(void)
 {
 	int ret;
-	char *device_name, *device_names;
+	char *device_name, *device_names, *device_tmp;
 	struct binder_device *device;
 	struct hlist_node *tmp;
 
@@ -5851,7 +5851,8 @@
 	}
 	strcpy(device_names, binder_devices_param);
 
-	while ((device_name = strsep(&device_names, ","))) {
+	device_tmp = device_names;
+	while ((device_name = strsep(&device_tmp, ","))) {
 		ret = init_binder_device(device_name);
 		if (ret)
 			goto err_init_binder_device_failed;
@@ -5865,6 +5866,9 @@
 		hlist_del(&device->hlist);
 		kfree(device);
 	}
+
+	kfree(device_names);
+
 err_alloc_device_names_failed:
 	debugfs_remove_recursive(binder_debugfs_dir_entry_root);