Re: [PATCH v3] mtd: spi-nor: fix memory leak when using debugfs_lookup()

From: Greg Kroah-Hartman
Date: Wed Feb 08 2023 - 10:55:23 EST


On Wed, Feb 08, 2023 at 04:28:45PM +0100, Michael Walle wrote:
> > +static void __exit spi_nor_module_exit(void)
> > +{
> > + spi_nor_debugfs_shutdown();
> > + spi_mem_driver_unregister(&spi_nor_driver);
>
> Hm, does the order matter here? I didn't test it, but this will
> lead to:
>
> rootdir = debugfs_create_dir("spi-nor", NULL);
> nor->debugfs_root = debugfs_create_dir("spi0", rootdir);
> debugfs_remove(rootdir);
> debugfs_remove(nor->debugfs_root);
>
> If that's ok, then this looks good.

It's ok as the last call to debugfs_remove() will just fail as that
dentry is long gone. Not the nicest, so I'll reverse them and send out
a v4 now.

thanks,

greg k-h