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 1572ACCA485 for ; Mon, 13 Jun 2022 11:46:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355658AbiFMLqv (ORCPT ); Mon, 13 Jun 2022 07:46:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41196 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357065AbiFMLp3 (ORCPT ); Mon, 13 Jun 2022 07:45:29 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 91F39B63; Mon, 13 Jun 2022 03:51:39 -0700 (PDT) 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 ams.source.kernel.org (Postfix) with ESMTPS id 059A7B80E07; Mon, 13 Jun 2022 10:51:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 63B48C34114; Mon, 13 Jun 2022 10:51:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655117496; bh=jMZXmEP/+RK0uQl0NLibbp+SHDtq/RGALhCcm54ehP8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q58wUsw/QOIDN3URvAwdPhSa/1MJRXy4fETA5uyh8K5IOsjdcSA1AQUCBROtvbEgK lSDjhrDSfpfl4dCCuo4qrKsqiAaZe4mySAQ5yA8loAKcvxJ+bqgndvdsR2EegV79Rt ypjDJsNCqPfTrQSLnBmxyrf9jB4foJzEi1wMybuo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, bumwoo lee , Chanwoo Choi , Sasha Levin Subject: [PATCH 5.4 378/411] extcon: Modify extcon device to be created after driver data is set Date: Mon, 13 Jun 2022 12:10:51 +0200 Message-Id: <20220613094940.006563268@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220613094928.482772422@linuxfoundation.org> References: <20220613094928.482772422@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: stable@vger.kernel.org From: bumwoo lee [ Upstream commit 5dcc2afe716d69f5112ce035cb14f007461ff189 ] Currently, someone can invoke the sysfs such as state_show() intermittently before dev_set_drvdata() is done. And it can be a cause of kernel Oops because of edev is Null at that time. So modified the driver registration to after setting drviver data. - Oops's backtrace. Backtrace: [] (state_show) from [] (dev_attr_show) [] (dev_attr_show) from [] (sysfs_kf_seq_show) [] (sysfs_kf_seq_show) from [] (kernfs_seq_show) [] (kernfs_seq_show) from [] (seq_read) [] (seq_read) from [] (kernfs_fop_read) [] (kernfs_fop_read) from [] (__vfs_read) [] (__vfs_read) from [] (vfs_read) [] (vfs_read) from [] (ksys_read) [] (ksys_read) from [] (sys_read) [] (sys_read) from [] (__sys_trace_return) Signed-off-by: bumwoo lee Signed-off-by: Chanwoo Choi Signed-off-by: Sasha Levin --- drivers/extcon/extcon.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c index 5c9e156cd086..6b905c3d30f4 100644 --- a/drivers/extcon/extcon.c +++ b/drivers/extcon/extcon.c @@ -1230,19 +1230,14 @@ int extcon_dev_register(struct extcon_dev *edev) edev->dev.type = &edev->extcon_dev_type; } - ret = device_register(&edev->dev); - if (ret) { - put_device(&edev->dev); - goto err_dev; - } - spin_lock_init(&edev->lock); - edev->nh = devm_kcalloc(&edev->dev, edev->max_supported, - sizeof(*edev->nh), GFP_KERNEL); - if (!edev->nh) { - ret = -ENOMEM; - device_unregister(&edev->dev); - goto err_dev; + if (edev->max_supported) { + edev->nh = kcalloc(edev->max_supported, sizeof(*edev->nh), + GFP_KERNEL); + if (!edev->nh) { + ret = -ENOMEM; + goto err_alloc_nh; + } } for (index = 0; index < edev->max_supported; index++) @@ -1253,6 +1248,12 @@ int extcon_dev_register(struct extcon_dev *edev) dev_set_drvdata(&edev->dev, edev); edev->state = 0; + ret = device_register(&edev->dev); + if (ret) { + put_device(&edev->dev); + goto err_dev; + } + mutex_lock(&extcon_dev_list_lock); list_add(&edev->entry, &extcon_dev_list); mutex_unlock(&extcon_dev_list_lock); @@ -1260,6 +1261,9 @@ int extcon_dev_register(struct extcon_dev *edev) return 0; err_dev: + if (edev->max_supported) + kfree(edev->nh); +err_alloc_nh: if (edev->max_supported) kfree(edev->extcon_dev_type.groups); err_alloc_groups: @@ -1320,6 +1324,7 @@ void extcon_dev_unregister(struct extcon_dev *edev) if (edev->max_supported) { kfree(edev->extcon_dev_type.groups); kfree(edev->cables); + kfree(edev->nh); } put_device(&edev->dev); -- 2.35.1