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Message-ID: <3572a765-17b4-b2df-e3d5-0d30485c4c67@linux.ibm.com>
Date:   Mon, 25 Apr 2022 10:38:12 +0200
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Subject: Re: ctcm: rename READ/WRITE defines to avoid redefinitions
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To:     "Colin King (gmail)" <colin.i.king@gmail.com>,
        Wenjia Zhang <wenjia@linux.ibm.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>
Cc:     Christian Borntraeger <borntraeger@linux.ibm.com>,
        linux-s390@vger.kernel.org,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
References: <ae612043-0252-e8c3-0773-912f116421c1@gmail.com>
From:   Alexandra Winter <wintera@linux.ibm.com>
In-Reply-To: <ae612043-0252-e8c3-0773-912f116421c1@gmail.com>
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On 24.04.22 20:58, Colin King (gmail) wrote:
> Hi,
> 
> static analysis with cppcheck detected a potential null pointer deference with the following commit:
> 
> commit 3c09e2647b5e1f1f9fd383971468823c2505e1b0
> Author: Ursula Braun <ursula.braun@de.ibm.com>
> Date:   Thu Aug 12 01:58:28 2010 +0000
> 
>     ctcm: rename READ/WRITE defines to avoid redefinitions
> 
> 
> The analysis is as follows:
> 
> drivers/s390/net/ctcm_sysfs.c:43:8: note: Assuming that condition 'priv' is not redundant
>  if (!(priv && priv->channel[CTCM_READ] && ndev)) {
>        ^
> drivers/s390/net/ctcm_sysfs.c:42:9: note: Null pointer dereference
>  ndev = priv->channel[CTCM_READ]->netdev;
> 
> The code in question is as follows:
> 
>         ndev = priv->channel[CTCM_READ]->netdev;
> 
>         ^^ priv may be null, as per check below but it is being dereferenced when assigning ndev
> 
>         if (!(priv && priv->channel[CTCM_READ] && ndev)) {
>                 CTCM_DBF_TEXT(SETUP, CTC_DBF_ERROR, "bfnondev");
>                 return -ENODEV;
>         }
> 
> Colin

Thank you very much for reporting this, we will provide a patch.

Do you have any special requests for the Reported-by flag? Or is
Reported-by: Colin King (gmail) <colin.i.king@gmail.com>
fine with you?

Kind regards
Alexandra