From patchwork Tue Jul 12 13:55:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yingliang X-Patchwork-Id: 590267 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AF8D9C433EF for ; Tue, 12 Jul 2022 13:45:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233208AbiGLNps (ORCPT ); Tue, 12 Jul 2022 09:45:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35210 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232579AbiGLNpm (ORCPT ); Tue, 12 Jul 2022 09:45:42 -0400 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7709D2B271; Tue, 12 Jul 2022 06:45:41 -0700 (PDT) Received: from dggpemm500022.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4Lj26F3fklzlVqb; Tue, 12 Jul 2022 21:44:05 +0800 (CST) Received: from dggpemm500007.china.huawei.com (7.185.36.183) by dggpemm500022.china.huawei.com (7.185.36.162) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 12 Jul 2022 21:45:39 +0800 Received: from huawei.com (10.175.103.91) by dggpemm500007.china.huawei.com (7.185.36.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 12 Jul 2022 21:45:38 +0800 From: Yang Yingliang To: , CC: Subject: [PATCH] Revert "spi: simplify devm_spi_register_controller" Date: Tue, 12 Jul 2022 21:55:04 +0800 Message-ID: <20220712135504.1055688-1-yangyingliang@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.175.103.91] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpemm500007.china.huawei.com (7.185.36.183) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org This reverts commit 59ebbe40fb51e307032ae7f63b2749fad2d4635a. If devm_add_action() fails in devm_add_action_or_reset(), devm_spi_unregister() will be called, it decreases the refcount of 'ctlr->dev' to 0, then it will cause uaf in the drivers that calling spi_put_controller() in error path. Fixes: 59ebbe40fb51 ("spi: simplify devm_spi_register_controller") Signed-off-by: Yang Yingliang --- drivers/spi/spi.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index dc1a324e3271..ef751ccd65be 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -3130,9 +3130,9 @@ int spi_register_controller(struct spi_controller *ctlr) } EXPORT_SYMBOL_GPL(spi_register_controller); -static void devm_spi_unregister(void *ctlr) +static void devm_spi_unregister(struct device *dev, void *res) { - spi_unregister_controller(ctlr); + spi_unregister_controller(*(struct spi_controller **)res); } /** @@ -3151,13 +3151,22 @@ static void devm_spi_unregister(void *ctlr) int devm_spi_register_controller(struct device *dev, struct spi_controller *ctlr) { + struct spi_controller **ptr; int ret; + ptr = devres_alloc(devm_spi_unregister, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + ret = spi_register_controller(ctlr); - if (ret) - return ret; + if (!ret) { + *ptr = ctlr; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } - return devm_add_action_or_reset(dev, devm_spi_unregister, ctlr); + return ret; } EXPORT_SYMBOL_GPL(devm_spi_register_controller);