From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from esa3.hgst.iphmx.com ([216.71.153.141]:55859 "EHLO esa3.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932661AbdGSQFf (ORCPT ); Wed, 19 Jul 2017 12:05:35 -0400 From: Bart Van Assche To: "yagmur.oymak@gmail.com" , "linux-kernel@vger.kernel.org" , "linux-block@vger.kernel.org" Subject: Re: 4.12 NULL pointer dereference in kmem_cache_free on USB storage removal Date: Wed, 19 Jul 2017 16:04:48 +0000 Message-ID: <1500480287.2494.1.camel@wdc.com> References: <1499980058.2740.22.camel@wdc.com> <952856d9-5f6b-98db-98e3-6348d428e894@gmail.com> In-Reply-To: <952856d9-5f6b-98db-98e3-6348d428e894@gmail.com> Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org On Wed, 2017-07-19 at 08:13 +0300, Yagmur Oymak wrote: > On 07/14/2017 12:07 AM, Bart Van Assche wrote: > > On Thu, 2017-07-13 at 23:24 +0300, Meelis Roos wrote: > > > [258062.320700] RIP: 0010:kmem_cache_free+0x12/0x160 > > > [258062.320886] Call Trace: > > > [258062.320897] scsi_exit_rq+0x4d/0x60 > > > [258062.320909] free_request_size+0x1c/0x30 > > > [258062.320923] mempool_destroy+0x1d/0x60 > > > [258062.320935] blk_exit_rl+0x1b/0x40 > > > [258062.320946] __blk_release_queue+0x7d/0x120 > > > [258062.320959] process_one_work+0x1af/0x340 > > > [258062.320972] worker_thread+0x43/0x3e0 > > > [258062.320984] kthread+0xfe/0x130 > > > [258062.320995] ? create_worker+0x170/0x170 > > > [258062.321007] ? kthread_create_on_node+0x40/0x40 > > > [258062.321022] ret_from_fork+0x22/0x30 > >=20 > > Thank you for your report. Can you apply commit 8e6882545d8c ("scsi: Av= oid > > that scsi_exit_rq() triggers a use-after-free") on top of kernel v4.12 = and > > retest? That commit has been tagged "Cc: stable" so I hope that this pa= tch > > will be included in kernel v4.12.1. However, that kernel is not yet ava= ilable > > unfortunately ... >=20 > That patch fixes the problem, as far as I tested. However, it still is > not included in stable by 4.12.2. The problem persists there, and is > fixed when this patch is applied on top of it. What to to about it?=20 =20 Hello Yagmur, [ Please don't top-post -- this is considered annoying in the Linux communi= ty ] Since kernel v4.13-rc1 has been released and since commit 8e6882545d8c is i= ncluded in v4.13-rc1 I assume that it won't take long before a stable kernel is rel= eased that includes that commit. BTW, Greg just announced that that commit will b= e included in the next v4.11 stable kernel. See also https://lkml.org/lkml/2017/7/19/4= 94. Bart.=