From patchwork Mon Dec 7 08:17:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 339467 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 235E1C4361B for ; Mon, 7 Dec 2020 08:27:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B25CB225A9 for ; Mon, 7 Dec 2020 08:27:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726083AbgLGI0k (ORCPT ); Mon, 7 Dec 2020 03:26:40 -0500 Received: from bmailout1.hostsharing.net ([83.223.95.100]:58561 "EHLO bmailout1.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726016AbgLGI0k (ORCPT ); Mon, 7 Dec 2020 03:26:40 -0500 Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (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 1B31B30000D04; Mon, 7 Dec 2020 09:25:22 +0100 (CET) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 9451E369; Mon, 7 Dec 2020 09:25:58 +0100 (CET) Message-Id: <6d97628b536baf01d5e3e39db61108f84d44c8b2.1607286887.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Mon, 7 Dec 2020 09:17:04 +0100 Subject: [PATCH 04/17] spi: spi-sh: Fix use-after-free on unbind To: Mark Brown Cc: linux-spi@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org spi_sh_remove() accesses the driver's private data after calling spi_unregister_master() even though that function releases the last reference on the spi_master 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: 680c1305e259 ("spi/spi_sh: use spi_unregister_master instead of spi_master_put in remove path") Signed-off-by: Lukas Wunner Cc: # v3.0+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation Cc: # v3.0+ Cc: Axel Lin --- drivers/spi/spi-sh.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) diff --git a/drivers/spi/spi-sh.c b/drivers/spi/spi-sh.c index 20bdae5fdf3b..15123a8f41e1 100644 --- a/drivers/spi/spi-sh.c +++ b/drivers/spi/spi-sh.c @@ -440,7 +440,7 @@ static int spi_sh_probe(struct platform_device *pdev) if (irq < 0) return irq; - master = spi_alloc_master(&pdev->dev, sizeof(struct spi_sh_data)); + master = devm_spi_alloc_master(&pdev->dev, sizeof(struct spi_sh_data)); if (master == NULL) { dev_err(&pdev->dev, "spi_alloc_master error.\n"); return -ENOMEM; @@ -458,16 +458,14 @@ static int spi_sh_probe(struct platform_device *pdev) break; default: dev_err(&pdev->dev, "No support width\n"); - ret = -ENODEV; - goto error1; + return -ENODEV; } ss->irq = irq; ss->master = master; ss->addr = devm_ioremap(&pdev->dev, res->start, resource_size(res)); if (ss->addr == NULL) { dev_err(&pdev->dev, "ioremap error.\n"); - ret = -ENOMEM; - goto error1; + return -ENOMEM; } INIT_LIST_HEAD(&ss->queue); spin_lock_init(&ss->lock); @@ -477,7 +475,7 @@ static int spi_sh_probe(struct platform_device *pdev) ret = request_irq(irq, spi_sh_irq, 0, "spi_sh", ss); if (ret < 0) { dev_err(&pdev->dev, "request_irq error\n"); - goto error1; + return ret; } master->num_chipselect = 2; @@ -496,9 +494,6 @@ static int spi_sh_probe(struct platform_device *pdev) error3: free_irq(irq, ss); - error1: - spi_master_put(master); - return ret; }