From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934070AbdKGAaC (ORCPT ); Mon, 6 Nov 2017 19:30:02 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:54065 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933284AbdKGA37 (ORCPT ); Mon, 6 Nov 2017 19:29:59 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Kai =?UTF-8?Q?M=C3=A4kisara?=" , "Bodo Stroesser" , "Hannes Reinecke" , "Shirish Pargaonkar" , "Martin K. Petersen" , "Ewan D. Milne" Date: Mon, 06 Nov 2017 23:03:02 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 100/294] scsi: st: fix blk_get_queue usage In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Bodo Stroesser commit 180efde0a3f43dbe533e4be203c2918793482d4e upstream. If blk_queue_get() in st_probe fails, disk->queue must not be set to SDp->request_queue, as that would result in put_disk() dropping a not taken reference. Thus, disk->queue should be set only after a successful blk_queue_get(). Fixes: 2b5bebccd282 ("st: Take additional queue ref in st_probe") Signed-off-by: Bodo Stroesser Acked-by: Shirish Pargaonkar Signed-off-by: Hannes Reinecke Reviewed-by: Ewan D. Milne Acked-by: Kai Mäkisara Signed-off-by: Martin K. Petersen Signed-off-by: Ben Hutchings --- drivers/scsi/st.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/scsi/st.c +++ b/drivers/scsi/st.c @@ -4115,11 +4115,11 @@ static int st_probe(struct device *dev) kref_init(&tpnt->kref); tpnt->disk = disk; disk->private_data = &tpnt->driver; - disk->queue = SDp->request_queue; /* SCSI tape doesn't register this gendisk via add_disk(). Manually * take queue reference that release_disk() expects. */ - if (!blk_get_queue(disk->queue)) + if (!blk_get_queue(SDp->request_queue)) goto out_put_disk; + disk->queue = SDp->request_queue; tpnt->driver = &st_template; tpnt->device = SDp;