From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH] libata: add refcounting to ata_host Date: Tue, 13 Mar 2018 13:29:38 -0700 Message-ID: <20180313202938.GI2943022@devbig577.frc2.facebook.com> References: <20171113201037.GL983427@devbig577.frc2.facebook.com> <1520584481-9643-1-git-send-email-takondra@cisco.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1520584481-9643-1-git-send-email-takondra@cisco.com> Sender: linux-kernel-owner@vger.kernel.org To: Taras Kondratiuk Cc: Lin Ming , xe-linux-external@cisco.com, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-ide@vger.kernel.org On Fri, Mar 09, 2018 at 08:34:41AM +0000, Taras Kondratiuk wrote: > After commit 9a6d6a2ddabb ("ata: make ata port as parent device of scsi > host") manual driver unbind/remove causes use-after-free. > > Unbind unconditionally invokes devres_release_all() which calls > ata_host_release() and frees ata_host/ata_port memory while it is still > being referenced as a parent of SCSI host. When SCSI host is finally > released scsi_host_dev_release() calls put_device(parent) and accesses > freed ata_port memory. > > Add reference counting to make sure that ata_host lives long enough. > > Bug report: https://lkml.org/lkml/2017/11/1/945 > Fixes: 9a6d6a2ddabb ("ata: make ata port as parent device of scsi host") > Cc: Tejun Heo > Cc: Lin Ming > Cc: linux-ide@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Taras Kondratiuk Applied to libata/for-4.17. Thanks. -- tejun