From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753487AbcKRMAQ (ORCPT ); Fri, 18 Nov 2016 07:00:16 -0500 Received: from mga11.intel.com ([192.55.52.93]:47463 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752338AbcKRMAP (ORCPT ); Fri, 18 Nov 2016 07:00:15 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,509,1473145200"; d="scan'208";a="6041000" From: Alexander Shishkin To: Johan Hovold Cc: linux-kernel@vger.kernel.org, Johan Hovold Subject: Re: [PATCH] stm class: fix device leak in open error path In-Reply-To: <1477997094-29192-1-git-send-email-johan@kernel.org> References: <1477997094-29192-1-git-send-email-johan@kernel.org> User-Agent: Notmuch/0.22.1 (http://notmuchmail.org) Emacs/24.5.1 (x86_64-pc-linux-gnu) Date: Fri, 18 Nov 2016 13:55:58 +0200 Message-ID: <874m35f1dd.fsf@ashishki-desk.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Johan Hovold writes: > Make sure to drop the reference taken by class_find_device() also on > allocation errors in open(). > > Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for...") > Signed-off-by: Johan Hovold Good catch, thanks! I'm going to change it a bit to look like this if you don't mind: diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index 51f81d64ca..cf6c9ea14c 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -361,7 +361,7 @@ static int stm_char_open(struct inode *inode, struct file *file) struct stm_file *stmf; struct device *dev; unsigned int major = imajor(inode); - int err = -ENODEV; + int err = -ENOMEM; dev = class_find_device(&stm_class, NULL, &major, major_match); if (!dev) @@ -369,8 +369,9 @@ static int stm_char_open(struct inode *inode, struct file *file) stmf = kzalloc(sizeof(*stmf), GFP_KERNEL); if (!stmf) - return -ENOMEM; + goto err_put_device; + err = -ENODEV; stm_output_init(&stmf->output); stmf->stm = to_stm_device(dev); @@ -382,9 +383,10 @@ static int stm_char_open(struct inode *inode, struct file *file) return nonseekable_open(inode, file); err_free: + kfree(stmf); +err_put_device: /* matches class_find_device() above */ put_device(dev); - kfree(stmf); return err; } Regards, -- Alex