From patchwork Mon Dec 7 08:17:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 11955025 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=-13.7 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 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 D7F84C4361B for ; Mon, 7 Dec 2020 08:47:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A1D98227C3 for ; Mon, 7 Dec 2020 08:47:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726087AbgLGIrq (ORCPT ); Mon, 7 Dec 2020 03:47:46 -0500 Received: from bmailout2.hostsharing.net ([83.223.78.240]:50067 "EHLO bmailout2.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726024AbgLGIrq (ORCPT ); Mon, 7 Dec 2020 03:47:46 -0500 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 bmailout2.hostsharing.net (Postfix) with ESMTPS id 18FC728010393; Mon, 7 Dec 2020 09:46:48 +0100 (CET) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 11A8910DB; Mon, 7 Dec 2020 09:47:04 +0100 (CET) Message-Id: <4b05c65cf6f1ea3251484fe9a00b4c65478a1ae3.1607286887.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Mon, 7 Dec 2020 09:17:17 +0100 Subject: [PATCH 17/17] spi: atmel-quadspi: Fix use-after-free on unbind To: Mark Brown Cc: linux-spi@vger.kernel.org, Piotr Bugalski , Tudor Ambarus Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org atmel_qspi_remove() accesses the driver's private data after calling spi_unregister_controller() even though that function releases the last reference on the spi_controller and thereby frees the private data. Fix by switching over to the new devm_spi_alloc_master() helper which keeps the private data accessible until the driver has unbound. Fixes: 2d30ac5ed633 ("mtd: spi-nor: atmel-quadspi: Use spi-mem interface for atmel-quadspi driver") Signed-off-by: Lukas Wunner Cc: # v5.0+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation Cc: # v5.0+ Cc: Piotr Bugalski Reviewed-by: Tudor Ambarus --- drivers/spi/atmel-quadspi.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c index b44521d4a245..1742ccc1ad0e 100644 --- a/drivers/spi/atmel-quadspi.c +++ b/drivers/spi/atmel-quadspi.c @@ -535,7 +535,7 @@ static int atmel_qspi_probe(struct platform_device *pdev) struct resource *res; int irq, err = 0; - ctrl = spi_alloc_master(&pdev->dev, sizeof(*aq)); + ctrl = devm_spi_alloc_master(&pdev->dev, sizeof(*aq)); if (!ctrl) return -ENOMEM; @@ -557,8 +557,7 @@ static int atmel_qspi_probe(struct platform_device *pdev) aq->regs = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(aq->regs)) { dev_err(&pdev->dev, "missing registers\n"); - err = PTR_ERR(aq->regs); - goto exit; + return PTR_ERR(aq->regs); } /* Map the AHB memory */ @@ -566,8 +565,7 @@ static int atmel_qspi_probe(struct platform_device *pdev) aq->mem = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(aq->mem)) { dev_err(&pdev->dev, "missing AHB memory\n"); - err = PTR_ERR(aq->mem); - goto exit; + return PTR_ERR(aq->mem); } aq->mmap_size = resource_size(res); @@ -579,15 +577,14 @@ static int atmel_qspi_probe(struct platform_device *pdev) if (IS_ERR(aq->pclk)) { dev_err(&pdev->dev, "missing peripheral clock\n"); - err = PTR_ERR(aq->pclk); - goto exit; + return PTR_ERR(aq->pclk); } /* Enable the peripheral clock */ err = clk_prepare_enable(aq->pclk); if (err) { dev_err(&pdev->dev, "failed to enable the peripheral clock\n"); - goto exit; + return err; } aq->caps = of_device_get_match_data(&pdev->dev); @@ -638,8 +635,6 @@ static int atmel_qspi_probe(struct platform_device *pdev) clk_disable_unprepare(aq->qspick); disable_pclk: clk_disable_unprepare(aq->pclk); -exit: - spi_controller_put(ctrl); return err; }