From patchwork Thu Nov 10 02:55:30 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yingliang X-Patchwork-Id: 13038258 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 5C64FC433FE for ; Thu, 10 Nov 2022 02:57:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232487AbiKJC5F (ORCPT ); Wed, 9 Nov 2022 21:57:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232634AbiKJC5E (ORCPT ); Wed, 9 Nov 2022 21:57:04 -0500 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA04E24099 for ; Wed, 9 Nov 2022 18:57:03 -0800 (PST) Received: from dggpemm500023.china.huawei.com (unknown [172.30.72.57]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4N75yJ0zsmzJnZl; Thu, 10 Nov 2022 10:54:00 +0800 (CST) Received: from dggpemm500007.china.huawei.com (7.185.36.183) by dggpemm500023.china.huawei.com (7.185.36.83) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 10 Nov 2022 10:57:00 +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 15.1.2375.31; Thu, 10 Nov 2022 10:57:00 +0800 From: Yang Yingliang To: CC: , Subject: [PATCH v4 2/2] mmc: sdio: fix possible memory leak in some error path Date: Thu, 10 Nov 2022 10:55:30 +0800 Message-ID: <20221110025530.4106568-3-yangyingliang@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221110025530.4106568-1-yangyingliang@huawei.com> References: <20221110025530.4106568-1-yangyingliang@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.103.91] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggpemm500007.china.huawei.com (7.185.36.183) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org If sdio_add_func() or sdio_init_func() fails, sdio_remove_func() can not free the memory, because the sdio function is not presented in these two cases, it won't call put_device(). To fix these leaks, make sdio_func_present() only control whether device_del() needs to be called or not. Then, put_device() is called to give up the reference which was set in device_initialize(), the memory can be freed in sdio_release_func(). In error case in sdio_init_func(), the reference of 'card->dev' is not get, so set 'func->card' to NULL to avoid redundant put in sdio_free_func_cis(). Fixes: 3d10a1ba0d37 ("sdio: fix reference counting in sdio_remove_func()") Signed-off-by: Yang Yingliang --- drivers/mmc/core/sdio.c | 1 + drivers/mmc/core/sdio_bus.c | 8 ++++---- drivers/mmc/core/sdio_cis.c | 3 ++- 3 files changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c index f64b9ac76a5c..ff95fb6aa741 100644 --- a/drivers/mmc/core/sdio.c +++ b/drivers/mmc/core/sdio.c @@ -137,6 +137,7 @@ static int sdio_init_func(struct mmc_card *card, unsigned int fn) * It is okay to remove the function here even though we hold * the host lock as we haven't registered the device yet. */ + func->card = NULL; sdio_remove_func(func); return ret; } diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c index 266639504a94..da561658bdae 100644 --- a/drivers/mmc/core/sdio_bus.c +++ b/drivers/mmc/core/sdio_bus.c @@ -377,11 +377,11 @@ int sdio_add_func(struct sdio_func *func) */ void sdio_remove_func(struct sdio_func *func) { - of_node_put(func->dev.of_node); - if (!sdio_func_present(func)) - return; + if (!sdio_func_present(func)) { + device_del(&func->dev); + } - device_del(&func->dev); + of_node_put(func->dev.of_node); put_device(&func->dev); } diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c index a705ba6eff5b..d374460fba9b 100644 --- a/drivers/mmc/core/sdio_cis.c +++ b/drivers/mmc/core/sdio_cis.c @@ -439,6 +439,7 @@ void sdio_free_func_cis(struct sdio_func *func) * We have now removed the link to the tuples in the * card structure, so remove the reference. */ - put_device(&func->card->dev); + if (func->card) + put_device(&func->card->dev); }