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=-9.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 E317BC4741F for ; Fri, 30 Oct 2020 15:56:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 957552087E for ; Fri, 30 Oct 2020 15:56:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726890AbgJ3P4k (ORCPT ); Fri, 30 Oct 2020 11:56:40 -0400 Received: from relay4-d.mail.gandi.net ([217.70.183.196]:36591 "EHLO relay4-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726178AbgJ3P4k (ORCPT ); Fri, 30 Oct 2020 11:56:40 -0400 X-Originating-IP: 82.255.60.242 Received: from [192.168.0.28] (lns-bzn-39-82-255-60-242.adsl.proxad.net [82.255.60.242]) (Authenticated sender: hadess@hadess.net) by relay4-d.mail.gandi.net (Postfix) with ESMTPSA id A3A8AE000C; Fri, 30 Oct 2020 15:56:37 +0000 (UTC) Message-ID: <0145bd8636cb9f384e5e9b7149a7d9a90bc56825.camel@hadess.net> Subject: Re: [PATCH] USB: apple-mfi-fastcharge: fix reference leak in apple_mfi_fc_set_property From: Bastien Nocera To: Zhang Qilong Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org Date: Fri, 30 Oct 2020 16:56:36 +0100 In-Reply-To: <20201030154534.98294-1-zhangqilong3@huawei.com> References: <20201030154534.98294-1-zhangqilong3@huawei.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.1 (3.38.1-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Fri, 2020-10-30 at 23:45 +0800, Zhang Qilong wrote: > pm_runtime_get_sync() will increment pm usage counter even > it failed. Forgetting to call pm_runtime_put_noidle will > result in reference leak in apple_mfi_fc_set_property, so > we should fix it. > > Signed-off-by: Zhang Qilong It looks correct, but I don't know whether it's necessary. There's a boatload of users of that API that don't even check for the get_sync() retval, and loads more where it's checked but never acted upon. Do you intend to fix all those as well? > --- >  drivers/usb/misc/apple-mfi-fastcharge.c | 4 +++- >  1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/misc/apple-mfi-fastcharge.c > b/drivers/usb/misc/apple-mfi-fastcharge.c > index b403094a6b3a..9e1ad4536e36 100644 > --- a/drivers/usb/misc/apple-mfi-fastcharge.c > +++ b/drivers/usb/misc/apple-mfi-fastcharge.c > @@ -120,8 +120,10 @@ static int apple_mfi_fc_set_property(struct > power_supply *psy, >         dev_dbg(&mfi->udev->dev, "prop: %d\n", psp); >   >         ret = pm_runtime_get_sync(&mfi->udev->dev); > -       if (ret < 0) > +       if (ret < 0) { > +               pm_runtime_put_noidle(&mfi->udev->dev); >                 return ret; > +       } >   >         switch (psp) { >         case POWER_SUPPLY_PROP_CHARGE_TYPE: