Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763852AbdDSVyk (ORCPT ); Wed, 19 Apr 2017 17:54:40 -0400 Received: from mx2.mpynet.fi ([82.197.21.85]:26485 "EHLO mx2.mpynet.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753652AbdDSVyi (ORCPT ); Wed, 19 Apr 2017 17:54:38 -0400 X-Greylist: delayed 401 seconds by postgrey-1.27 at vger.kernel.org; Wed, 19 Apr 2017 17:54:37 EDT Date: Thu, 20 Apr 2017 00:47:54 +0300 From: Rakesh Pandit To: Matias Bjorling CC: , , Subject: [PATCH] ligtnvm: fix double blk_put_queue on same queue Message-ID: <20170419214754.GA7979@hercules.tuxera.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline User-Agent: Mutt/1.8.0 (2017-02-23) X-ClientProxiedBy: tuxera-exch.ad.tuxera.com (10.20.48.11) To tuxera-exch.ad.tuxera.com (10.20.48.11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2518 Lines: 56 On an error path in NVM_DEV_CREATE ioctl blk_put_queue is being called twice: one via blk_cleanup_queue and another via put_disk. Straight fix seems to remove queue pointer so that disk_release never ends up caling blk_put_queue again. [ 391.808827] WARNING: CPU: 1 PID: 1250 at lib/refcount.c:128 refcount_sub_and_test+0x70/0x80 [ 391.808830] refcount_t: underflow; use-after-free. [ 391.808832] Modules linked in: nf_conntrack_netbios_ns............ [ 391.809052] CPU: 1 PID: 1250 Comm: nvme Not tainted......... [ 391.809057] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014 [ 391.809060] Call Trace: [ 391.809079] dump_stack+0x63/0x86 [ 391.809094] __warn+0xcb/0xf0 [ 391.809103] warn_slowpath_fmt+0x5f/0x80 [ 391.809118] refcount_sub_and_test+0x70/0x80 [ 391.809125] refcount_dec_and_test+0x11/0x20 [ 391.809136] kobject_put+0x1f/0x60 [ 391.809149] blk_put_queue+0x15/0x20 [ 391.809159] disk_release+0xae/0xf0 [ 391.809172] device_release+0x32/0x90 [ 391.809184] kobject_release+0x6a/0x170 [ 391.809196] kobject_put+0x2f/0x60 [ 391.809206] put_disk+0x17/0x20 [ 391.809219] nvm_ioctl_dev_create.isra.16+0x897/0xa30 [ 391.809236] nvm_ctl_ioctl+0x23c/0x4c0 [ 391.809248] do_vfs_ioctl+0xa3/0x5f0 [ 391.809258] SyS_ioctl+0x79/0x90 [ 391.809271] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 391.809280] RIP: 0033:0x7f5d3ef363c7 [ 391.809286] RSP: 002b:00007ffc72ed8d78 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [ 391.809296] RAX: ffffffffffffffda RBX: 00007ffc72edb552 RCX: 00007f5d3ef363c7 [ 391.809301] RDX: 00007ffc72ed8d90 RSI: 0000000040804c22 RDI: 0000000000000003 [ 391.809306] RBP: 0000000000000001 R08: 0000000000000020 R09: 0000000000000001 [ 391.809311] R10: 000000000000053f R11: 0000000000000206 R12: 0000000000000000 [ 391.809316] R13: 0000000000000000 R14: 00007ffc72edb58d R15: 00007ffc72edb581 Signed-off-by: Rakesh Pandit --- drivers/lightnvm/core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c index 2c26af3..5d7aa45 100644 --- a/drivers/lightnvm/core.c +++ b/drivers/lightnvm/core.c @@ -309,6 +309,7 @@ static int nvm_create_tgt(struct nvm_dev *dev, struct nvm_ioctl_create *create) tt->exit(targetdata); err_init: blk_cleanup_queue(tqueue); + tdisk->queue = NULL; err_disk: put_disk(tdisk); err_dev: -- 2.5.5