Return-Path: <linux-kernel-owner+w=401wt.eu-S1751474AbXLCUo2@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1751474AbXLCUo2 (ORCPT <rfc822;w@1wt.eu>);
	Mon, 3 Dec 2007 15:44:28 -0500
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750866AbXLCUoU
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Mon, 3 Dec 2007 15:44:20 -0500
Received: from cantor.suse.de ([195.135.220.2]:50057 "EHLO mx1.suse.de"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1750782AbXLCUoT (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Mon, 3 Dec 2007 15:44:19 -0500
Date: Mon, 3 Dec 2007 12:47:16 -0800
From: Greg KH <gregkh@suse.de>
To: Alexey Dobriyan <adobriyan@sw.ru>
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, kay.sievers@vrfy.org
Subject: Re: kobject ->k_name memory leak
Message-ID: <20071203204716.GA9734@suse.de>
References: <20071203092607.GA22477@localhost.sw.ru>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20071203092607.GA22477@localhost.sw.ru>
User-Agent: Mutt/1.5.16 (2007-06-09)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 1438
Lines: 37

On Mon, Dec 03, 2007 at 12:26:07PM +0300, Alexey Dobriyan wrote:
> Hi, Greg!
> 
> Commit ce2c9cb0259acd2aed184499ebe41ab00da13b25 aka
> "kobject: remove the static array for the name" introduced memory leak
> of a module name after modprobe/rmmod. Apparently for modules ->release
> callback is NULL.
> 
> kobject_cleanup: ->release = 00000000, name = 'foo_sysctl'
> Pid: 1927, comm: rmmod Not tainted 2.6.24-rc3-e1cca7e8d484390169777b423a7fe46c7021fec1 #5
>  [<c10d4a58>] kobject_cleanup+0xb8/0xc0
>  [<c10d4a60>] kobject_release+0x0/0x10
>  [<c10d587b>] kref_put+0x2b/0xa0
>  [<c11dbe85>] _spin_unlock+0x25/0x40
>  [<c1045b78>] free_module+0x78/0xd0
>  [<c104773f>] sys_delete_module+0x12f/0x1a0

Hm, _which_ kobject associated with a module, there are 3 of them I
think :)

They should all have a release function, and if they do not, we think
it's a "static" kobject and it is not safe to free that name.

I've been working on cleaning this up a lot in the -mm tree with over 80
patches for the kset/kobject apis and interfaces.

But if we have a dynamic kobject, and we aren't freeing it properly,
please let me know which one it is and I'll work to fix it for 2.6.24.

thanks,

greg k-h
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/