From patchwork Sat Dec 5 23:14:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Belloni X-Patchwork-Id: 1411642 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-rtc-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=bootlin.com Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CpQRB1CCpz9sW9 for ; Sun, 6 Dec 2020 10:15:34 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726056AbgLEXPd (ORCPT ); Sat, 5 Dec 2020 18:15:33 -0500 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:38935 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726011AbgLEXPd (ORCPT ); Sat, 5 Dec 2020 18:15:33 -0500 X-Originating-IP: 86.194.74.19 Received: from localhost (lfbn-lyo-1-997-19.w86-194.abo.wanadoo.fr [86.194.74.19]) (Authenticated sender: alexandre.belloni@bootlin.com) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id 3D7DCFF802; Sat, 5 Dec 2020 23:14:51 +0000 (UTC) From: Alexandre Belloni To: Alessandro Zummo , Alexandre Belloni , Bartosz Golaszewski Cc: linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] rtc: fix RTC removal Date: Sun, 6 Dec 2020 00:14:48 +0100 Message-Id: <20201205231449.610980-1-alexandre.belloni@bootlin.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org Since the rtc_register_device, removing an RTC device will end with a refcount_t: underflow; use-after-free warning since put_device is called twice in the device tear down path. Fixes: fdcfd854333b ("rtc: rework rtc_register_device() resource management") Signed-off-by: Alexandre Belloni Reviewed-by: Bartosz Golaszewski --- drivers/rtc/class.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c index e6b44b7c4ad3..5c6748dfa55d 100644 --- a/drivers/rtc/class.c +++ b/drivers/rtc/class.c @@ -335,7 +335,6 @@ static void devm_rtc_unregister_device(void *data) cdev_device_del(&rtc->char_dev, &rtc->dev); rtc->ops = NULL; mutex_unlock(&rtc->ops_lock); - put_device(&rtc->dev); } static void devm_rtc_release_device(void *res)