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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32C1DC433FE for ; Thu, 13 Oct 2022 13:59:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229746AbiJMN7G (ORCPT ); Thu, 13 Oct 2022 09:59:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229638AbiJMN6e (ORCPT ); Thu, 13 Oct 2022 09:58:34 -0400 Received: from mail-pg1-x52a.google.com (mail-pg1-x52a.google.com [IPv6:2607:f8b0:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49F2082D18; Thu, 13 Oct 2022 06:57:54 -0700 (PDT) Received: by mail-pg1-x52a.google.com with SMTP id l6so1611280pgu.7; Thu, 13 Oct 2022 06:57:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :sender:from:to:cc:subject:date:message-id:reply-to; bh=sGCbtoZq8xW4BBmJD2BEfn6t+q0YI6YvtbXTTyy1Hmg=; b=UYnj+gymmvoScgVRFsb1PbkuongBvFu8ViIlnB5PjY+maxFwN1+uRES1RT/tV4Rxjt a+hVclk3CYldUXokamV8PRaEfhLNfUD0+eALszPYucB7VsNml+yJJegS+EcySTJk9n/p Bg/bkxZGpENHcpVrU+Xva0O+Cn85LBCpHXsisk/bKLo3qzW55Ithj61nzdFCIS1Onr8M KO6tWTd4qSTahlHWlUjpZtfr72NshYpzhL9u0X92eGPUEnIis4ejiYAMIAz1mR4/VqBT fOWWFR51JMmzX1daLh0lF8NSaTlus5jZhOtcsatrEg9bgAKmDIDnrdmGBcjl7HrjryMt GCww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :sender:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=sGCbtoZq8xW4BBmJD2BEfn6t+q0YI6YvtbXTTyy1Hmg=; b=QbqoavSY3usJNYaMlWY4WsWgiGPdnNWh/sL+LMnbCYRgzzOCQECScbzSkyODS32VrL CTvK+ptHmwlRriaDw/smlyQn+CSG2gUVc6Cg3KijOti3b1LIKllt+sYKshhxQ2vjlSFb m/d5XFFUlE+dAQpybgK/7qa0dCuvN3MP4AHQ6MYIsTpCY+X0J7A65P7zA8F2r6BkrsB4 VcTB7/e0vDuY+MuaJPFzkSwQjqGuSVqxZnnZCKl7lyLskxbsQXN/XQbCwUte9Yu1ZdVa Hcrf1JW2mhL19xRXQdgUKcrJckMdH+Phhe5m2kcfILNwgk91+hLzmVBxI0JU7bqEPCWf 8x8Q== X-Gm-Message-State: ACrzQf36Fv+oUdjhKxyn06qWf6B3V5OT7mQpCIXx/k9s4lBjj1+kmd34 64gd/p1zx3bV4wlGmKdu1GITRuK5jGU= X-Google-Smtp-Source: AMsMyM4LjSCoI19v1XmUSYkhwWFIO0pn2oRii409dEnca/pF5rbqf1z/h6ZWGEZoY4f6vfFJtqLWGg== X-Received: by 2002:a05:6a00:7ce:b0:562:b271:9854 with SMTP id n14-20020a056a0007ce00b00562b2719854mr35435951pfu.46.1665669198242; Thu, 13 Oct 2022 06:53:18 -0700 (PDT) Received: from ?IPV6:2600:1700:e321:62f0:329c:23ff:fee3:9d7c? ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id h9-20020a17090a054900b0020adf65cebbsm3295915pjf.8.2022.10.13.06.53.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 13 Oct 2022 06:53:11 -0700 (PDT) Sender: Guenter Roeck Message-ID: <29536273-4cd5-5530-083a-c8b8e42e1eb1@roeck-us.net> Date: Thu, 13 Oct 2022 06:53:10 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [PATCH] drivers: watchdog: exar_wdt.c fix use after free Content-Language: en-US To: Manank Patel Cc: linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org References: <20221013095439.1425108-1-pmanank200502@gmail.com> From: Guenter Roeck In-Reply-To: <20221013095439.1425108-1-pmanank200502@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/13/22 02:54, Manank Patel wrote: > fix use after free by storing the result of PTR_ERR(n->pdev) > to a local variable before returning. > > Signed-off-by: Manank Patel Reviewed-by: Guenter Roeck > --- > drivers/watchdog/exar_wdt.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/watchdog/exar_wdt.c b/drivers/watchdog/exar_wdt.c > index 35058d8b21bc..7c61ff343271 100644 > --- a/drivers/watchdog/exar_wdt.c > +++ b/drivers/watchdog/exar_wdt.c > @@ -355,8 +355,10 @@ static int __init exar_wdt_register(struct wdt_priv *priv, const int idx) > &priv->wdt_res, 1, > priv, sizeof(*priv)); > if (IS_ERR(n->pdev)) { > + int err = PTR_ERR(n->pdev); > + > kfree(n); > - return PTR_ERR(n->pdev); > + return err; > } > > list_add_tail(&n->list, &pdev_list);