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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 361D3C4361B for ; Thu, 10 Dec 2020 18:49:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E219323100 for ; Thu, 10 Dec 2020 18:49:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732392AbgLJOcK (ORCPT ); Thu, 10 Dec 2020 09:32:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:38582 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390291AbgLJOag (ORCPT ); Thu, 10 Dec 2020 09:30:36 -0500 From: Greg Kroah-Hartman Authentication-Results: mail.kernel.org; dkim=permerror (bad message/signature format) To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sascha Hauer , Florian Fainelli , Lukas Wunner , Vladimir Oltean , Mark Brown Subject: [PATCH 4.9 39/45] spi: bcm2835: Fix use-after-free on unbind Date: Thu, 10 Dec 2020 15:26:53 +0100 Message-Id: <20201210142604.275692434@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201210142602.361598591@linuxfoundation.org> References: <20201210142602.361598591@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lukas Wunner [ Upstream commit e1483ac030fb4c57734289742f1c1d38dca61e22 ] bcm2835_spi_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: f8043872e796 ("spi: add driver for BCM2835") Reported-by: Sascha Hauer Reported-by: Florian Fainelli Signed-off-by: Lukas Wunner Cc: # v3.10+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation Cc: # v3.10+ Cc: Vladimir Oltean Tested-by: Florian Fainelli Acked-by: Florian Fainelli Link: https://lore.kernel.org/r/ad66e0a0ad96feb848814842ecf5b6a4539ef35c.1605121038.git.lukas@wunner.de Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spi-bcm2835.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -737,7 +737,7 @@ static int bcm2835_spi_probe(struct plat struct resource *res; int err; - master = spi_alloc_master(&pdev->dev, sizeof(*bs)); + master = devm_spi_alloc_master(&pdev->dev, sizeof(*bs)); if (!master) { dev_err(&pdev->dev, "spi_alloc_master() failed\n"); return -ENOMEM; @@ -759,23 +759,20 @@ static int bcm2835_spi_probe(struct plat res = platform_get_resource(pdev, IORESOURCE_MEM, 0); bs->regs = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(bs->regs)) { - err = PTR_ERR(bs->regs); - goto out_master_put; - } + if (IS_ERR(bs->regs)) + return PTR_ERR(bs->regs); bs->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(bs->clk)) { err = PTR_ERR(bs->clk); dev_err(&pdev->dev, "could not get clk: %d\n", err); - goto out_master_put; + return err; } bs->irq = platform_get_irq(pdev, 0); if (bs->irq <= 0) { dev_err(&pdev->dev, "could not get IRQ: %d\n", bs->irq); - err = bs->irq ? bs->irq : -ENODEV; - goto out_master_put; + return bs->irq ? bs->irq : -ENODEV; } clk_prepare_enable(bs->clk); @@ -803,8 +800,6 @@ static int bcm2835_spi_probe(struct plat out_clk_disable: clk_disable_unprepare(bs->clk); -out_master_put: - spi_master_put(master); return err; }