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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0C016C282C2 for ; Thu, 7 Feb 2019 22:21:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D83FA2147C for ; Thu, 7 Feb 2019 22:21:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727021AbfBGWVU convert rfc822-to-8bit (ORCPT ); Thu, 7 Feb 2019 17:21:20 -0500 Received: from relay8-d.mail.gandi.net ([217.70.183.201]:58597 "EHLO relay8-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726731AbfBGWVT (ORCPT ); Thu, 7 Feb 2019 17:21:19 -0500 X-Originating-IP: 91.224.148.103 Received: from xps13 (unknown [91.224.148.103]) (Authenticated sender: miquel.raynal@bootlin.com) by relay8-d.mail.gandi.net (Postfix) with ESMTPSA id 1B7DD1BF206; Thu, 7 Feb 2019 22:21:14 +0000 (UTC) Date: Thu, 7 Feb 2019 23:21:13 +0100 From: Miquel Raynal To: Wen Yang Cc: "bbrezillon@kernel.org" , "tudor.ambarus@microchip.com" , "richard@nod.at" , "dwmw2@infradead.org" , "computersforpeace@gmail.com" , "marek.vasut@gmail.com" , "nicolas.ferre@microchip.com" , "alexandre.belloni@bootlin.com" , "ludovic.desroches@microchip.com" , "linux-mtd@lists.infradead.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v5 1/3] mtd: rawnand: atmel: fix possible object reference leak Message-ID: <20190207232113.5dc026af@xps13> In-Reply-To: References: Organization: Bootlin X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Wen, Wen Yang wrote on Thu, 7 Feb 2019 11:56:48 +0000: > of_find_device_by_node() takes a reference to the struct device > when it finds a match via get_device, there is no need to call > get_device() twice. > We also should make sure to drop the reference to the device > taken by of_find_device_by_node() on driver unbind. > > Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver") > Signed-off-by: Wen Yang > --- > v5->v4: Add new line, add people in Cc and remove all Cc lines. > v4->v3: Avoid two times of calling grtform_get_drvdata() > v3->v2: Change the commit message. > v2->v1: Add missing Fixes tag. > > drivers/mtd/nand/raw/atmel/pmecc.c | 22 ++++++++++++++++------ > 1 file changed, 16 insertions(+), 6 deletions(-) > > diff --git a/drivers/mtd/nand/raw/atmel/pmecc.c b/drivers/mtd/nand/raw/atmel/pmecc.c > index 555a74e..97e47ea 100644 > --- a/drivers/mtd/nand/raw/atmel/pmecc.c > +++ b/drivers/mtd/nand/raw/atmel/pmecc.c > @@ -876,23 +876,33 @@ static struct atmel_pmecc *atmel_pmecc_get_by_node(struct device *userdev, > { > struct platform_device *pdev; > struct atmel_pmecc *pmecc, **ptr; > + int ret; > > pdev = of_find_device_by_node(np); > - if (!pdev || !platform_get_drvdata(pdev)) > + if (!pdev) > return ERR_PTR(-EPROBE_DEFER); > > - ptr = devres_alloc(devm_atmel_pmecc_put, sizeof(*ptr), GFP_KERNEL); > - if (!ptr) > - return ERR_PTR(-ENOMEM); > - > - get_device(&pdev->dev); > pmecc = platform_get_drvdata(pdev); > + if (!pmecc) { > + ret = -EPROBE_DEFER; > + goto err_put_device; > + } > + > + ptr = devres_alloc(devm_atmel_pmecc_put, sizeof(*ptr), GFP_KERNEL); > + if (!ptr) { > + ret = -ENOMEM; > + goto err_put_device; > + } > > *ptr = pmecc; > > devres_add(userdev, ptr); > > return pmecc; > + > +err_put_device: > + put_device(&pdev->dev); > + return ERR_PTR(ret); > } > > static const int atmel_pmecc_strengths[] = { 2, 4, 8, 12, 24, 32 }; Series applied to nand/next. Thanks, Miquèl