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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9A4EC4167D for ; Tue, 31 Oct 2023 09:15:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343797AbjJaJPg (ORCPT ); Tue, 31 Oct 2023 05:15:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43748 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343798AbjJaJPf (ORCPT ); Tue, 31 Oct 2023 05:15:35 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1FCC1B3 for ; Tue, 31 Oct 2023 02:15:33 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 831B3C433C7; Tue, 31 Oct 2023 09:15:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698743732; bh=7oplT+YM28cUrUNIm/lBOFgyzcINYapHF+yPlXaobfU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ruZ0YQx9vaWIhWglymgueIkr3T3wK1wtGzyf+BZAv2JWVq8yGUJF2y+N98s4MTK+R syICxfj6cfK+EOhf9GsWFdWn+RrTvzUTUD0CVeRg6abTxbKtAhPAabYu6zpAHmF+BO X6HuerNzhxW7GiLW5qpxM9pjziofGC5s82pjuGsIl3jrffkXzL4JpCgovH30Kllasq r4zbpHBMRx4J6YzU4E3jTbLkiLQhqpmqZGMtyEI+LZdmp7slFvIDgEHjVMsikFQzB0 vbTa/2AJTl50Kzac7Juyg1b4RGz/zpB05JJ5UeB/Nuq8lGKq1iqJ5TQlNFYxLgI8KZ hxEU1ok4Ai9jw== From: Lee Jones To: lee@kernel.org Cc: stable@vger.kernel.org, Krzysztof Kozlowski , Marek Szyprowski , Greg Kroah-Hartman Subject: [PATCH 4/6] rpmsg: Fix calling device_lock() on non-initialized device Date: Tue, 31 Oct 2023 09:15:15 +0000 Message-ID: <20231031091521.2223075-4-lee@kernel.org> X-Mailer: git-send-email 2.42.0.820.g83a721a137-goog In-Reply-To: <20231031091521.2223075-1-lee@kernel.org> References: <20231031091521.2223075-1-lee@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Krzysztof Kozlowski commit bb17d110cbf270d5247a6e261c5ad50e362d1675 upstream. driver_set_override() helper uses device_lock() so it should not be called before rpmsg_register_device() (which calls device_register()). Effect can be seen with CONFIG_DEBUG_MUTEXES: DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: CPU: 3 PID: 57 at kernel/locking/mutex.c:582 __mutex_lock+0x1ec/0x430 ... Call trace: __mutex_lock+0x1ec/0x430 mutex_lock_nested+0x44/0x50 driver_set_override+0x124/0x150 qcom_glink_native_probe+0x30c/0x3b0 glink_rpm_probe+0x274/0x350 platform_probe+0x6c/0xe0 really_probe+0x17c/0x3d0 __driver_probe_device+0x114/0x190 driver_probe_device+0x3c/0xf0 ... Refactor the rpmsg_register_device() function to use two-step device registering (initialization + add) and call driver_set_override() in proper moment. This moves the code around, so while at it also NULL-ify the rpdev->driver_override in error path to be sure it won't be kfree() second time. Fixes: 42cd402b8fd4 ("rpmsg: Fix kfree() of static memory on setting driver_override") Reported-by: Marek Szyprowski Signed-off-by: Krzysztof Kozlowski Tested-by: Marek Szyprowski Link: https://lore.kernel.org/r/20220429195946.1061725-2-krzysztof.kozlowski@linaro.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Lee Jones Change-Id: I37c19feae515b3721a0013615d47886a7b1108de --- drivers/rpmsg/rpmsg_core.c | 33 ++++++++++++++++++++++++++++++--- drivers/rpmsg/rpmsg_internal.h | 14 +------------- drivers/rpmsg/rpmsg_ns.c | 4 +--- include/linux/rpmsg.h | 8 ++++++++ 4 files changed, 40 insertions(+), 19 deletions(-) diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index c544dee0b5dd9..0ea8f8ec84efc 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -569,24 +569,51 @@ static struct bus_type rpmsg_bus = { .remove = rpmsg_dev_remove, }; -int rpmsg_register_device(struct rpmsg_device *rpdev) +/* + * A helper for registering rpmsg device with driver override and name. + * Drivers should not be using it, but instead rpmsg_register_device(). + */ +int rpmsg_register_device_override(struct rpmsg_device *rpdev, + const char *driver_override) { struct device *dev = &rpdev->dev; int ret; + if (driver_override) + strcpy(rpdev->id.name, driver_override); + dev_set_name(&rpdev->dev, "%s.%s.%d.%d", dev_name(dev->parent), rpdev->id.name, rpdev->src, rpdev->dst); rpdev->dev.bus = &rpmsg_bus; - ret = device_register(&rpdev->dev); + device_initialize(dev); + if (driver_override) { + ret = driver_set_override(dev, &rpdev->driver_override, + driver_override, + strlen(driver_override)); + if (ret) { + dev_err(dev, "device_set_override failed: %d\n", ret); + return ret; + } + } + + ret = device_add(dev); if (ret) { - dev_err(dev, "device_register failed: %d\n", ret); + dev_err(dev, "device_add failed: %d\n", ret); + kfree(rpdev->driver_override); + rpdev->driver_override = NULL; put_device(&rpdev->dev); } return ret; } +EXPORT_SYMBOL(rpmsg_register_device_override); + +int rpmsg_register_device(struct rpmsg_device *rpdev) +{ + return rpmsg_register_device_override(rpdev, NULL); +} EXPORT_SYMBOL(rpmsg_register_device); /* diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index 5f4f3691bbf1e..7985af92aa489 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -90,19 +90,7 @@ int rpmsg_release_channel(struct rpmsg_device *rpdev, */ static inline int rpmsg_chrdev_register_device(struct rpmsg_device *rpdev) { - int ret; - - strcpy(rpdev->id.name, "rpmsg_chrdev"); - ret = driver_set_override(&rpdev->dev, &rpdev->driver_override, - rpdev->id.name, strlen(rpdev->id.name)); - if (ret) - return ret; - - ret = rpmsg_register_device(rpdev); - if (ret) - kfree(rpdev->driver_override); - - return ret; + return rpmsg_register_device_override(rpdev, "rpmsg_ctrl"); } #endif diff --git a/drivers/rpmsg/rpmsg_ns.c b/drivers/rpmsg/rpmsg_ns.c index 762ff1ae279f2..c70ad03ff2e90 100644 --- a/drivers/rpmsg/rpmsg_ns.c +++ b/drivers/rpmsg/rpmsg_ns.c @@ -20,12 +20,10 @@ */ int rpmsg_ns_register_device(struct rpmsg_device *rpdev) { - strcpy(rpdev->id.name, "rpmsg_ns"); - rpdev->driver_override = "rpmsg_ns"; rpdev->src = RPMSG_NS_ADDR; rpdev->dst = RPMSG_NS_ADDR; - return rpmsg_register_device(rpdev); + return rpmsg_register_device_override(rpdev, "rpmsg_ns"); } EXPORT_SYMBOL(rpmsg_ns_register_device); diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h index 1b7294cefb807..a63c5a4ff3e15 100644 --- a/include/linux/rpmsg.h +++ b/include/linux/rpmsg.h @@ -165,6 +165,8 @@ static inline __rpmsg64 cpu_to_rpmsg64(struct rpmsg_device *rpdev, u64 val) #if IS_ENABLED(CONFIG_RPMSG) +int rpmsg_register_device_override(struct rpmsg_device *rpdev, + const char *driver_override); int rpmsg_register_device(struct rpmsg_device *rpdev); int rpmsg_unregister_device(struct device *parent, struct rpmsg_channel_info *chinfo); @@ -190,6 +192,12 @@ __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, #else +static inline int rpmsg_register_device_override(struct rpmsg_device *rpdev, + const char *driver_override) +{ + return -ENXIO; +} + static inline int rpmsg_register_device(struct rpmsg_device *rpdev) { return -ENXIO; -- 2.42.0.820.g83a721a137-goog