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=-14.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 B03A3C433E0 for ; Thu, 18 Mar 2021 18:58:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F71B64F01 for ; Thu, 18 Mar 2021 18:58:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232673AbhCRS5t (ORCPT ); Thu, 18 Mar 2021 14:57:49 -0400 Received: from mail-oi1-f179.google.com ([209.85.167.179]:41518 "EHLO mail-oi1-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232674AbhCRS50 (ORCPT ); Thu, 18 Mar 2021 14:57:26 -0400 Received: by mail-oi1-f179.google.com with SMTP id z15so2048420oic.8; Thu, 18 Mar 2021 11:57:26 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ndTWQxWMaQ8uWEc77N/kRP4OQQx2E++l4s9Oim2oRcU=; b=RCAfxJD8I6uJ659FMEmGiLLlMgjBemPAymZUdNYUMlwFoFdkn4noS+M/H4+as5feDB fmhH1tmfZAIisk5K2TFaA3vbcuHQqVcWmGTW1NCPhGfAaxv4/MVIArUcBOZopso0Vb3s Zy2S/Di3qjgmp9aCLbRo9odjbCsA9ByIpVyVoyl0KO2FGwt9BnVc/jn+3R/iNnjkmtFl kgOiHpC5uYbGh7zKTKmC1lACGob9OK4fpuYNo5+Bsu1fMhtmuKkphCfwCciE4V+FRKL2 yZJJm/oxrKXldGjDYYrGYO1CXltkCHQYobG4DBYWv9+7rP6a9r7dgrpGOoRH6cGKYmRA m1vA== X-Gm-Message-State: AOAM531jT4m/HcszVbAhdHxc+nzpkw7elWHfJsMJWYhDc3EzTCXDCuFA uWgC4lGtC/0bDhYK5zj/4Lm0xe6hMb5vSzJOreMsfIhJ X-Google-Smtp-Source: ABdhPJyBz0jBzMa2nMYKm228ff0yu8NZjN7i2Z/l2AHysD7tXUljAB4QtS/+5uM1uF86sVxSkb09YhJRlM7x1p6lOTo= X-Received: by 2002:aca:5fc3:: with SMTP id t186mr3977844oib.69.1616093846293; Thu, 18 Mar 2021 11:57:26 -0700 (PDT) MIME-Version: 1.0 References: <20210207224648.8137-1-colin.king@canonical.com> In-Reply-To: <20210207224648.8137-1-colin.king@canonical.com> From: "Rafael J. Wysocki" Date: Thu, 18 Mar 2021 19:57:14 +0100 Message-ID: Subject: Re: [PATCH] PM / Domains: Fix integer overflows on u32 bit multiplies To: Colin King Cc: "Rafael J . Wysocki" , Kevin Hilman , Ulf Hansson , Pavel Machek , Len Brown , Greg Kroah-Hartman , Marc Titinger , Lina Iyer , Linux PM , kernel-janitors@vger.kernel.org, Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Feb 7, 2021 at 11:47 PM Colin King wrote: > > From: Colin Ian King > > There are three occurrances of u32 variables being multiplied by > 1000 using 32 bit multiplies and the result being assigned to a > 64 bit signed integer. These can potentially lead to a 32 bit > overflows, so fix this by casting 1000 to a UL first to force > a 64 bit multiply hence avoiding the overflow. > > Addresses-Coverity: ("Unintentional integer overflow") > Fixes: 30f604283e05 ("PM / Domains: Allow domain power states to be read from DT") > Signed-off-by: Colin Ian King > --- > drivers/base/power/domain.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c > index aaf6c83b5cf6..ddeff69126ff 100644 > --- a/drivers/base/power/domain.c > +++ b/drivers/base/power/domain.c > @@ -2831,10 +2831,10 @@ static int genpd_parse_state(struct genpd_power_state *genpd_state, > > err = of_property_read_u32(state_node, "min-residency-us", &residency); > if (!err) > - genpd_state->residency_ns = 1000 * residency; > + genpd_state->residency_ns = 1000UL * residency; Wouldn't it be better to use NSEC_PER_USEC here and below? > > - genpd_state->power_on_latency_ns = 1000 * exit_latency; > - genpd_state->power_off_latency_ns = 1000 * entry_latency; > + genpd_state->power_on_latency_ns = 1000UL * exit_latency; > + genpd_state->power_off_latency_ns = 1000UL * entry_latency; > genpd_state->fwnode = &state_node->fwnode; > > return 0; > -- > 2.29.2 >