From patchwork Mon Feb 11 23:47:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 10807013 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 35D241390 for ; Mon, 11 Feb 2019 23:47:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 256032AE8B for ; Mon, 11 Feb 2019 23:47:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 179962AEF7; Mon, 11 Feb 2019 23:47:21 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.7 required=2.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9AD552AE8B for ; Mon, 11 Feb 2019 23:47:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727330AbfBKXrT (ORCPT ); Mon, 11 Feb 2019 18:47:19 -0500 Received: from esa6.hgst.iphmx.com ([216.71.154.45]:14651 "EHLO esa6.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727122AbfBKXrT (ORCPT ); Mon, 11 Feb 2019 18:47:19 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1549928840; x=1581464840; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=xeencaVU0zzDDnuC7Mrp3HNbHWbTnU3Mqs3piQX/xW0=; b=Yo63PetLF2KWPIKcbAiQsFkhwevv4009+eTqGYytDxxfS+3OzHfy378F YC690d8mvOu0aTU7sMmovdzksx+NlDh+d2BMqBulUExyvzyXQPmbPJTmg jLkF7FXVdArcI07YyZsO2jqmXNi68w+fH+fYlE7x4mZgy8b0cFk1fGxOm UbUxzUDKwqN+F4RZlU5xtuYYSwNz4WEFnh5RQM+MZ9mW5ryAOJdc9ZqC+ 4ZU+CbaS3J6UJpdueNdh88AN5QNTZ1VxvDRSpWLQecgtMfRdmSr1pBJp1 chJR44uhwAVKf1ZgQy5+pgg3T0ocz6dXK0HM4Y00Rj2tpU6LO3FmeN1s9 w==; X-IronPort-AV: E=Sophos;i="5.58,360,1544457600"; d="scan'208";a="102736660" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 12 Feb 2019 07:47:19 +0800 Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep02.wdc.com with ESMTP; 11 Feb 2019 15:27:56 -0800 Received: from washi.fujisawa.hgst.com ([10.149.53.254]) by uls-op-cesaip02.wdc.com with ESMTP; 11 Feb 2019 15:47:17 -0800 From: Damien Le Moal To: linux-block@vger.kernel.org, Jens Axboe Cc: Matias Bjorling Subject: [PATCH v3] nullb: Prevent use of legacy request queue mode Date: Tue, 12 Feb 2019 08:47:16 +0900 Message-Id: <20190211234716.18816-1-damien.lemoal@wdc.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When null_blk queue mode is specified together with modprobe/insmod, a check to prevent setting the nullb device queue mode to 1 (NULL_Q_RQ) is done. However, the same check is not performed when setting up a nullb device through configfs, resulting in a oops (NULL pointer dereference for the device request queue). Fix this problem by checking for an invalid queue mode value in null_validate_conf(), propagating -EINVAL to null_add_dev() if the queue mode is NULL_Q_RQ. While at it, also fix the propagation to user space of null_add_dev() return value when a nullb device is created through the power attribute of configfs. Finally, remove the "1=rq" value from the list of possible values of the queue_mode module argument to make it clear that this is no longer a valid setting. Fixes: e50b1e327aeb ("null_blk: remove legacy IO path") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal --- Changes from v2: * Fixed "Fixes" tag Changes from v1: * Removed reference to rq mode from queue_mode description drivers/block/null_blk_main.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/drivers/block/null_blk_main.c b/drivers/block/null_blk_main.c index 62c9654b9ce8..155dcef3b21a 100644 --- a/drivers/block/null_blk_main.c +++ b/drivers/block/null_blk_main.c @@ -130,7 +130,7 @@ static const struct kernel_param_ops null_queue_mode_param_ops = { }; device_param_cb(queue_mode, &null_queue_mode_param_ops, &g_queue_mode, 0444); -MODULE_PARM_DESC(queue_mode, "Block interface to use (0=bio,1=rq,2=multiqueue)"); +MODULE_PARM_DESC(queue_mode, "Block interface to use (0=bio,2=multiqueue)"); static int g_gb = 250; module_param_named(gb, g_gb, int, 0444); @@ -318,9 +318,10 @@ static ssize_t nullb_device_power_store(struct config_item *item, if (!dev->power && newp) { if (test_and_set_bit(NULLB_DEV_FL_UP, &dev->flags)) return count; - if (null_add_dev(dev)) { + ret = null_add_dev(dev); + if (ret) { clear_bit(NULLB_DEV_FL_UP, &dev->flags); - return -ENOMEM; + return ret; } set_bit(NULLB_DEV_FL_CONFIGURED, &dev->flags); @@ -1561,8 +1562,13 @@ static int null_init_tag_set(struct nullb *nullb, struct blk_mq_tag_set *set) return blk_mq_alloc_tag_set(set); } -static void null_validate_conf(struct nullb_device *dev) +static int null_validate_conf(struct nullb_device *dev) { + if (dev->queue_mode == NULL_Q_RQ) { + pr_err("null_blk: legacy IO path no longer available\n"); + return -EINVAL; + } + dev->blocksize = round_down(dev->blocksize, 512); dev->blocksize = clamp_t(unsigned int, dev->blocksize, 512, 4096); @@ -1588,6 +1594,8 @@ static void null_validate_conf(struct nullb_device *dev) /* can not stop a queue */ if (dev->queue_mode == NULL_Q_BIO) dev->mbps = 0; + + return 0; } #ifdef CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION @@ -1620,7 +1628,9 @@ static int null_add_dev(struct nullb_device *dev) struct nullb *nullb; int rv; - null_validate_conf(dev); + rv = null_validate_conf(dev); + if (rv) + goto out; nullb = kzalloc_node(sizeof(*nullb), GFP_KERNEL, dev->home_node); if (!nullb) { @@ -1648,8 +1658,10 @@ static int null_add_dev(struct nullb_device *dev) if (rv) goto out_cleanup_queues; - if (!null_setup_fault()) + if (!null_setup_fault()) { + rv = -EINVAL; goto out_cleanup_queues; + } nullb->tag_set->timeout = 5 * HZ; nullb->q = blk_mq_init_queue(nullb->tag_set);