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 B9243C7618D for ; Thu, 6 Apr 2023 11:34:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237901AbjDFLe3 (ORCPT ); Thu, 6 Apr 2023 07:34:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238085AbjDFLdx (ORCPT ); Thu, 6 Apr 2023 07:33:53 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D021AA5D6; Thu, 6 Apr 2023 04:32:52 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 123346464C; Thu, 6 Apr 2023 11:32:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4C49AC433A4; Thu, 6 Apr 2023 11:32:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1680780769; bh=lSOBpUnFu9VK1D1fFEX3s0tqrCknH4atbNI6skVNVjY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XzzNv0IY13mLchZSFuYrIR3OP/k8RrF6sGBSMyO+tPshHpjD9w3/IwoDBmKXvcbpQ nkX0aDkbqS6/PbX5kgFTvjVt8Guac7gtwyAhvzpzbFQV/C5aqlpcHAlXMvzCo0fMFH Wc/0ZB5VVL1f7JBjlx1SZWaD8spypccdC1P0x8LLsGqAPu17BNT7eSpO0KxU6NN2EL QgXtboraXgYOb7pMb7QhskD4iSvzs2DGMfOf6jF19VqinN9dryrD6H9vpFAmC7vp7x cyuafDG/DewESvrAeQqnkv4yBtA9Bp2BuSyxU61AEDy/uIGO/Vez8sgDk31qp9gLlM rncsLKPvyxSVA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Tudor Ambarus , Pratyush Yadav , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , linux-mtd@lists.infradead.org, Michael Walle , Sasha Levin , tudor.ambarus@linaro.org Subject: [PATCH AUTOSEL 6.1 17/17] mtd: spi-nor: fix memory leak when using debugfs_lookup() Date: Thu, 6 Apr 2023 07:32:11 -0400 Message-Id: <20230406113211.648424-17-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230406113211.648424-1-sashal@kernel.org> References: <20230406113211.648424-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg Kroah-Hartman [ Upstream commit ec738ca127d07ecac6afae36e2880341ec89150e ] When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To solve this, remove the lookup and create the directory on the first device found, and then remove it when the module is unloaded. Cc: Tudor Ambarus Cc: Pratyush Yadav Cc: Miquel Raynal Cc: Richard Weinberger Cc: Vignesh Raghavendra Cc: linux-mtd@lists.infradead.org Reviewed-by: Michael Walle Link: https://lore.kernel.org/r/20230208160230.2179905-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/mtd/spi-nor/core.c | 14 +++++++++++++- drivers/mtd/spi-nor/core.h | 2 ++ drivers/mtd/spi-nor/debugfs.c | 11 ++++++++--- 3 files changed, 23 insertions(+), 4 deletions(-) diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index cda57cb863089..75e694791d8d9 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -3272,7 +3272,19 @@ static struct spi_mem_driver spi_nor_driver = { .remove = spi_nor_remove, .shutdown = spi_nor_shutdown, }; -module_spi_mem_driver(spi_nor_driver); + +static int __init spi_nor_module_init(void) +{ + return spi_mem_driver_register(&spi_nor_driver); +} +module_init(spi_nor_module_init); + +static void __exit spi_nor_module_exit(void) +{ + spi_mem_driver_unregister(&spi_nor_driver); + spi_nor_debugfs_shutdown(); +} +module_exit(spi_nor_module_exit); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Huang Shijie "); diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h index d18dafeb020ab..00bf0d0e955a0 100644 --- a/drivers/mtd/spi-nor/core.h +++ b/drivers/mtd/spi-nor/core.h @@ -709,8 +709,10 @@ static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd) #ifdef CONFIG_DEBUG_FS void spi_nor_debugfs_register(struct spi_nor *nor); +void spi_nor_debugfs_shutdown(void); #else static inline void spi_nor_debugfs_register(struct spi_nor *nor) {} +static inline void spi_nor_debugfs_shutdown(void) {} #endif #endif /* __LINUX_MTD_SPI_NOR_INTERNAL_H */ diff --git a/drivers/mtd/spi-nor/debugfs.c b/drivers/mtd/spi-nor/debugfs.c index df76cb5de3f93..5f56b23205d8b 100644 --- a/drivers/mtd/spi-nor/debugfs.c +++ b/drivers/mtd/spi-nor/debugfs.c @@ -226,13 +226,13 @@ static void spi_nor_debugfs_unregister(void *data) nor->debugfs_root = NULL; } +static struct dentry *rootdir; + void spi_nor_debugfs_register(struct spi_nor *nor) { - struct dentry *rootdir, *d; + struct dentry *d; int ret; - /* Create rootdir once. Will never be deleted again. */ - rootdir = debugfs_lookup(SPI_NOR_DEBUGFS_ROOT, NULL); if (!rootdir) rootdir = debugfs_create_dir(SPI_NOR_DEBUGFS_ROOT, NULL); @@ -247,3 +247,8 @@ void spi_nor_debugfs_register(struct spi_nor *nor) debugfs_create_file("capabilities", 0444, d, nor, &spi_nor_capabilities_fops); } + +void spi_nor_debugfs_shutdown(void) +{ + debugfs_remove(rootdir); +} -- 2.39.2