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Message-ID: <21328530d3f15c75abca8107823a4578e5065ca6.camel@intel.com>
Subject: Re: iwlwifi: refactor the SAR tables from mvm to acpi
From:   Luciano Coelho <luciano.coelho@intel.com>
To:     Colin Ian King <colin.king@canonical.com>,
        Johannes Berg <johannes.berg@intel.com>,
        Emmanuel Grumbach <emmanuel.grumbach@intel.com>,
        Intel Linux Wireless <linuxwifi@intel.com>,
        Kalle Valo <kvalo@codeaurora.org>,
        "David S. Miller" <davem@davemloft.net>,
        Ihab Zhaika <ihab.zhaika@intel.com>,
        Shahar S Matityahu <shahar.s.matityahu@intel.com>,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Date:   Fri, 20 Dec 2019 07:40:44 +0200
In-Reply-To: <18ea9fa8-93fe-f371-68ee-3d12eac252c8@canonical.com>
References: <18ea9fa8-93fe-f371-68ee-3d12eac252c8@canonical.com>
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On Fri, 2019-12-20 at 00:02 +0000, Colin Ian King wrote:
> Hi,
> 
> Static analysis with Coverity has detected a potential issue with the
> following commit:
> 
> commit 39c1a9728f938c7255ce507c8d56b73e8a4ebddf
> Author: Ihab Zhaika <ihab.zhaika@intel.com>
> Date:   Fri Nov 15 09:28:11 2019 +0200
> 
>     iwlwifi: refactor the SAR tables from mvm to acpi
> 
> 
> in function iwl_sar_get_ewrd_table() we have an array index pos being
> initialized to 3 and then incremented each time a loop iterates:
> 
>         for (i = 0; i < n_profiles; i++) {
>                 /* the tables start at element 3 */
>                 int pos = 3;
> 
>                 /* The EWRD profiles officially go from 2 to 4, but we
>                  * save them in sar_profiles[1-3] (because we don't
>                  * have profile 0).  So in the array we start from 1.
>                  */
>                 ret = iwl_sar_set_profile(&wifi_pkg->package.elements[pos],
>                                           &fwrt->sar_profiles[i + 1],
>                                           enabled);
>                 if (ret < 0)
>                         break;
> 
>                 /* go to the next table */
>                 pos += ACPI_SAR_TABLE_SIZE;
>         }
> 
> So, each iteration is always accessing package.elements[3]. I'm not sure
> if that is intentional. If it is, then the increment of pos is not
> required.  Either way, it's not clear what the original intention is.

Good catch, thanks! We'll fix it.

--
Cheers,
Luca.