From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751888Ab2I2WJU (ORCPT ); Sat, 29 Sep 2012 18:09:20 -0400 Received: from mail-wg0-f44.google.com ([74.125.82.44]:63366 "EHLO mail-wg0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751712Ab2I2WJT (ORCPT ); Sat, 29 Sep 2012 18:09:19 -0400 Message-ID: <1348956554.7401.1.camel@maxim-laptop> Subject: Re: [patch 1/2] memstick: use after free in msb_disk_release() From: Maxim Levitsky To: Dan Carpenter Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Andrew Morton , Jens Axboe Date: Sun, 30 Sep 2012 00:09:14 +0200 In-Reply-To: <20120929071104.GB10993@elgon.mountain> References: <20120929071104.GB10993@elgon.mountain> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2012-09-29 at 10:11 +0300, Dan Carpenter wrote: > The original code dereferenced "msb" after freeing it. > > Signed-off-by: Dan Carpenter > > diff --git a/drivers/memstick/core/ms_block.c b/drivers/memstick/core/ms_block.c > index c815fe5..a8e8915 100644 > --- a/drivers/memstick/core/ms_block.c > +++ b/drivers/memstick/core/ms_block.c > @@ -1983,9 +1983,9 @@ static int msb_disk_release(struct gendisk *disk) > msb->usage_count--; > > if (!msb->usage_count) { > - kfree(msb); > disk->private_data = NULL; > idr_remove(&msb_disk_idr, msb->disk_id); > + kfree(msb); > put_disk(disk); > } > } Oops, I added this bug in latest iteration, when removed support for major. Acked-by: Maxim Levitsky Best regards, Maxim Levitsky