From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4447AC3526C for ; Sat, 5 Dec 2020 18:44:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1D9D8230FE for ; Sat, 5 Dec 2020 18:44:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726038AbgLEQts (ORCPT ); Sat, 5 Dec 2020 11:49:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726629AbgLEQqZ (ORCPT ); Sat, 5 Dec 2020 11:46:25 -0500 Received: from bmailout1.hostsharing.net (bmailout1.hostsharing.net [IPv6:2a01:37:1000::53df:5f64:0]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B9ACC02A186 for ; Sat, 5 Dec 2020 08:45:35 -0800 (PST) Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.hostsharing.net", Issuer "COMODO RSA Domain Validation Secure Server CA" (not verified)) by bmailout1.hostsharing.net (Postfix) with ESMTPS id ECF0830000D17; Sat, 5 Dec 2020 17:44:56 +0100 (CET) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 0343D9033; Sat, 5 Dec 2020 17:45:34 +0100 (CET) Date: Sat, 5 Dec 2020 17:45:33 +0100 From: Lukas Wunner To: gregkh@linuxfoundation.org, Sudip Mukherjee Cc: broonie@kernel.org, f.fainelli@gmail.com, kdasu.kdev@gmail.com, stable@vger.kernel.org Subject: Re: FAILED: patch "[PATCH] spi: bcm-qspi: Fix use-after-free on unbind" failed to apply to 4.9-stable tree Message-ID: <20201205164533.GB28458@wunner.de> References: <20201205153509.GA22211@wunner.de> <16061215704518@kroah.com> <20201205164110.GA28458@wunner.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201205164110.GA28458@wunner.de> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Nov 23, 2020 at 09:52:50AM +0100, gregkh@linuxfoundation.org wrote: > The patch below does not apply to the 4.9-stable tree. > If someone wants it applied there, or to any other stable or longterm > tree, then please email the backport, including the original git commit > id to . Below please find the backport of 63c5395bb7a9 to the 4.9-stable tree. It depends on the backport of 5e844cc37a5c I just sent out. Thanks! -- >8 -- Subject: [PATCH] spi: bcm-qspi: Fix use-after-free on unbind [ Upstream commit 63c5395bb7a9777a33f0e7b5906f2c0170a23692 ] bcm_qspi_remove() calls spi_unregister_master() even though bcm_qspi_probe() calls devm_spi_register_master(). The spi_master is therefore unregistered and freed twice on unbind. Fix by switching over to the new devm_spi_alloc_master() helper which keeps the private data accessible until the driver has unbound. While at it, fix an ordering issue in bcm_qspi_remove() wherein spi_unregister_master() is called after uninitializing the hardware, disabling the clock and freeing an IRQ data structure. The correct order is to call spi_unregister_master() *before* those teardown steps because bus accesses may still be ongoing until that function returns. Fixes: fa236a7ef240 ("spi: bcm-qspi: Add Broadcom MSPI driver") Signed-off-by: Lukas Wunner Cc: # v4.9+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation Cc: # v4.9+ Cc: Kamal Dasu Acked-by: Florian Fainelli Tested-by: Florian Fainelli Link: https://lore.kernel.org/r/5e31a9a59fd1c0d0b795b2fe219f25e5ee855f9d.1605121038.git.lukas@wunner.de Signed-off-by: Mark Brown --- drivers/spi/spi-bcm-qspi.c | 34 ++++++++++++---------------------- 1 file changed, 12 insertions(+), 22 deletions(-) diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c index 1906b2319e5b..5453910d8abc 100644 --- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -1185,7 +1185,7 @@ int bcm_qspi_probe(struct platform_device *pdev, if (!of_match_node(bcm_qspi_of_match, dev->of_node)) return -ENODEV; - master = spi_alloc_master(dev, sizeof(struct bcm_qspi)); + master = devm_spi_alloc_master(dev, sizeof(struct bcm_qspi)); if (!master) { dev_err(dev, "error allocating spi_master\n"); return -ENOMEM; @@ -1218,21 +1218,17 @@ int bcm_qspi_probe(struct platform_device *pdev, if (res) { qspi->base[MSPI] = devm_ioremap_resource(dev, res); - if (IS_ERR(qspi->base[MSPI])) { - ret = PTR_ERR(qspi->base[MSPI]); - goto qspi_resource_err; - } + if (IS_ERR(qspi->base[MSPI])) + return PTR_ERR(qspi->base[MSPI]); } else { - goto qspi_resource_err; + return 0; } res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "bspi"); if (res) { qspi->base[BSPI] = devm_ioremap_resource(dev, res); - if (IS_ERR(qspi->base[BSPI])) { - ret = PTR_ERR(qspi->base[BSPI]); - goto qspi_resource_err; - } + if (IS_ERR(qspi->base[BSPI])) + return PTR_ERR(qspi->base[BSPI]); qspi->bspi_mode = true; } else { qspi->bspi_mode = false; @@ -1243,18 +1239,14 @@ int bcm_qspi_probe(struct platform_device *pdev, res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cs_reg"); if (res) { qspi->base[CHIP_SELECT] = devm_ioremap_resource(dev, res); - if (IS_ERR(qspi->base[CHIP_SELECT])) { - ret = PTR_ERR(qspi->base[CHIP_SELECT]); - goto qspi_resource_err; - } + if (IS_ERR(qspi->base[CHIP_SELECT])) + return PTR_ERR(qspi->base[CHIP_SELECT]); } qspi->dev_ids = kcalloc(num_irqs, sizeof(struct bcm_qspi_dev_id), GFP_KERNEL); - if (!qspi->dev_ids) { - ret = -ENOMEM; - goto qspi_resource_err; - } + if (!qspi->dev_ids) + return -ENOMEM; for (val = 0; val < num_irqs; val++) { irq = -1; @@ -1330,7 +1322,7 @@ int bcm_qspi_probe(struct platform_device *pdev, qspi->xfer_mode.addrlen = -1; qspi->xfer_mode.hp = -1; - ret = devm_spi_register_master(&pdev->dev, master); + ret = spi_register_master(master); if (ret < 0) { dev_err(dev, "can't register master\n"); goto qspi_reg_err; @@ -1343,8 +1335,6 @@ int bcm_qspi_probe(struct platform_device *pdev, clk_disable_unprepare(qspi->clk); qspi_probe_err: kfree(qspi->dev_ids); -qspi_resource_err: - spi_master_put(master); return ret; } /* probe function to be called by SoC specific platform driver probe */ @@ -1355,10 +1345,10 @@ int bcm_qspi_remove(struct platform_device *pdev) struct bcm_qspi *qspi = platform_get_drvdata(pdev); platform_set_drvdata(pdev, NULL); + spi_unregister_master(qspi->master); bcm_qspi_hw_uninit(qspi); clk_disable_unprepare(qspi->clk); kfree(qspi->dev_ids); - spi_unregister_master(qspi->master); return 0; } -- 2.29.2