From nobody Mon Apr 13 18:36:53 2026 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 D3319C4332F for ; Wed, 16 Nov 2022 07:45:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232272AbiKPHpV (ORCPT ); Wed, 16 Nov 2022 02:45:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231594AbiKPHpR (ORCPT ); Wed, 16 Nov 2022 02:45:17 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EAFD8DEE5 for ; Tue, 15 Nov 2022 23:45:15 -0800 (PST) Received: from kwepemi500024.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NBw3B2Wt2zqST7; Wed, 16 Nov 2022 15:41:26 +0800 (CST) Received: from huawei.com (10.175.103.91) by kwepemi500024.china.huawei.com (7.221.188.100) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Wed, 16 Nov 2022 15:45:13 +0800 From: Zeng Heng To: , , , CC: , , Subject: [PATCH v2] regulator: core: fix kobject release warning and memory leak in regulator_register() Date: Wed, 16 Nov 2022 15:43:39 +0800 Message-ID: <20221116074339.1024240-1-zengheng4@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.103.91] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemi500024.china.huawei.com (7.221.188.100) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Here is a warning report about lack of registered release() from kobject lib: Device '(null)' does not have a release() function, it is broken and must b= e fixed. WARNING: CPU: 0 PID: 48430 at drivers/base/core.c:2332 device_release+0x104= /0x120 Call Trace: kobject_put+0xdc/0x180 put_device+0x1b/0x30 regulator_register+0x651/0x1170 devm_regulator_register+0x4f/0xb0 When regulator_register() returns fail and directly goto `clean` symbol, rdev->dev has not registered release() function yet (which is registered by regulator_class in the following), so rdev needs to be freed manually. If rdev->dev.of_node is not NULL, which means the of_node has gotten by regulator_of_get_init_data(), it needs to call of_node_put() to avoid refcount leak. Otherwise, only calling put_device() would lead memory leak of rdev in further: unreferenced object 0xffff88810d0b1000 (size 2048): comm "107-i2c-rtq6752", pid 48430, jiffies 4342258431 (age 1341.780s) backtrace: kmalloc_trace+0x22/0x110 regulator_register+0x184/0x1170 devm_regulator_register+0x4f/0xb0 When regulator_register() returns fail and goto `wash` symbol, rdev->dev has registered release() function, so directly call put_device() to cleanup everything. Fixes: d3c731564e09 ("regulator: plug of_node leak in regulator_register()'= s error path") Signed-off-by: Zeng Heng --- drivers/regulator/core.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index bcccad8f7516..77126cb1ae8c 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -5644,11 +5644,15 @@ regulator_register(const struct regulator_desc *reg= ulator_desc, mutex_lock(®ulator_list_mutex); regulator_ena_gpio_free(rdev); mutex_unlock(®ulator_list_mutex); + put_device(&rdev->dev); + rdev =3D NULL; clean: if (dangling_of_gpiod) gpiod_put(config->ena_gpiod); + if (rdev && rdev->dev.of_node) + of_node_put(rdev->dev.of_node); + kfree(rdev); kfree(config); - put_device(&rdev->dev); rinse: if (dangling_cfg_gpiod) gpiod_put(cfg->ena_gpiod); --=20 2.25.1