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 0AD3EC54EBE for ; Mon, 16 Jan 2023 17:07:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232879AbjAPRHm (ORCPT ); Mon, 16 Jan 2023 12:07:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234119AbjAPRHY (ORCPT ); Mon, 16 Jan 2023 12:07:24 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E677D40BF8 for ; Mon, 16 Jan 2023 08:48:02 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 1025C61086 for ; Mon, 16 Jan 2023 16:48:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 22CCEC433D2; Mon, 16 Jan 2023 16:48:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1673887681; bh=bdUd0jJz8TzKLTNhUP4X/1O/nvogaSqkKYzgCxU67zk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MetU7Qpr4HO90khSm6CkGcUkmep7rx+VJNljQEY81WDHmHELXYP9qb8KIoNqhhdN3 F3GOyL0geOQsvk1dSZxvsAzXutOXzMTxFj9q5154AQvIG8bNOgXeiUn8wTG4BExQ9k TBDxysm7kh5MXYLcK31TiIDH6Q4+yn4wFDs5pPbg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yang Yingliang , Sasha Levin Subject: [PATCH 4.19 242/521] chardev: fix error handling in cdev_device_add() Date: Mon, 16 Jan 2023 16:48:24 +0100 Message-Id: <20230116154857.973741580@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230116154847.246743274@linuxfoundation.org> References: <20230116154847.246743274@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yang Yingliang [ Upstream commit 11fa7fefe3d8fac7da56bc9aa3dd5fb3081ca797 ] While doing fault injection test, I got the following report: ------------[ cut here ]------------ kobject: '(null)' (0000000039956980): is not initialized, yet kobject_put() is being called. WARNING: CPU: 3 PID: 6306 at kobject_put+0x23d/0x4e0 CPU: 3 PID: 6306 Comm: 283 Tainted: G W 6.1.0-rc2-00005-g307c1086d7c9 #1253 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:kobject_put+0x23d/0x4e0 Call Trace: cdev_device_add+0x15e/0x1b0 __iio_device_register+0x13b4/0x1af0 [industrialio] __devm_iio_device_register+0x22/0x90 [industrialio] max517_probe+0x3d8/0x6b4 [max517] i2c_device_probe+0xa81/0xc00 When device_add() is injected fault and returns error, if dev->devt is not set, cdev_add() is not called, cdev_del() is not needed. Fix this by checking dev->devt in error path. Fixes: 233ed09d7fda ("chardev: add helper function to register char devs with a struct device") Signed-off-by: Yang Yingliang Link: https://lore.kernel.org/r/20221202030237.520280-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- fs/char_dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/char_dev.c b/fs/char_dev.c index 5fffd5050fb7..2c3d519b21c2 100644 --- a/fs/char_dev.c +++ b/fs/char_dev.c @@ -553,7 +553,7 @@ int cdev_device_add(struct cdev *cdev, struct device *dev) } rc = device_add(dev); - if (rc) + if (rc && dev->devt) cdev_del(cdev); return rc; -- 2.35.1