From patchwork Thu Apr 2 13:14:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin Ian King X-Patchwork-Id: 1265585 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-rtc-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=canonical.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 48tNpF0T02z9sR4 for ; Fri, 3 Apr 2020 00:15:00 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388254AbgDBNO7 (ORCPT ); Thu, 2 Apr 2020 09:14:59 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:40925 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726252AbgDBNO7 (ORCPT ); Thu, 2 Apr 2020 09:14:59 -0400 Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1jJzg9-0005VX-I1; Thu, 02 Apr 2020 13:14:41 +0000 From: Colin King To: Alessandro Zummo , Alexandre Belloni , Guenter Roeck , Chris Packham , linux-rtc@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH][next] rtc: ds1307: check for failed memory allocation on wdt Date: Thu, 2 Apr 2020 14:14:41 +0100 Message-Id: <20200402131441.539088-1-colin.king@canonical.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Sender: linux-rtc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rtc@vger.kernel.org From: Colin Ian King Currently a failed memory allocation will lead to a null pointer dereference on point wdt. Fix this by checking for a failed allocation and adding error return handling to function ds1307_wdt_register. Addresses-Coverity: ("Dereference null return") Fixes: fd90d48db037 ("rtc: ds1307: add support for watchdog timer on ds1388") Signed-off-by: Colin Ian King --- drivers/rtc/rtc-ds1307.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index fad042118862..95c5b6facc59 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -1665,14 +1665,16 @@ static const struct watchdog_ops ds1388_wdt_ops = { }; -static void ds1307_wdt_register(struct ds1307 *ds1307) +static int ds1307_wdt_register(struct ds1307 *ds1307) { struct watchdog_device *wdt; if (ds1307->type != ds_1388) - return; + return 0; wdt = devm_kzalloc(ds1307->dev, sizeof(*wdt), GFP_KERNEL); + if (!wdt) + return -ENOMEM; wdt->info = &ds1388_wdt_info; wdt->ops = &ds1388_wdt_ops; @@ -1683,10 +1685,13 @@ static void ds1307_wdt_register(struct ds1307 *ds1307) watchdog_init_timeout(wdt, 0, ds1307->dev); watchdog_set_drvdata(wdt, ds1307); devm_watchdog_register_device(ds1307->dev, wdt); + + return 0; } #else -static void ds1307_wdt_register(struct ds1307 *ds1307) +static int ds1307_wdt_register(struct ds1307 *ds1307) { + return 0; } #endif /* CONFIG_WATCHDOG_CORE */ @@ -1979,9 +1984,9 @@ static int ds1307_probe(struct i2c_client *client, ds1307_hwmon_register(ds1307); ds1307_clks_register(ds1307); - ds1307_wdt_register(ds1307); + err = ds1307_wdt_register(ds1307); - return 0; + return err; exit: return err;