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Subject: Re: [PATCH][next] thermal: qcom: tsens-v1: fix kfree of a non-pointer
 value
To:     Amit Kucheria <amit.kucheria@linaro.org>,
        Colin King <colin.king@canonical.com>
Cc:     Andy Gross <agross@kernel.org>, Zhang Rui <rui.zhang@intel.com>,
        Eduardo Valentin <edubezval@gmail.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        AngeloGioacchino Del Regno <kholk11@gmail.com>,
        Linux PM list <linux-pm@vger.kernel.org>,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>,
        kernel-janitors@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
References: <20191022111806.23143-1-colin.king@canonical.com>
 <CAP245DXjVDJ68kmWONmWh4YB=dcVrQ4q1y3bPncDc5=FohY2Vw@mail.gmail.com>
From:   Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Message-ID: <10cbe6fb-05b8-3219-cef5-05980559f053@linaro.org>
Date:   Tue, 22 Oct 2019 17:44:21 +0100
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On 22/10/2019 14:06, Amit Kucheria wrote:
> On Tue, Oct 22, 2019 at 4:48 PM Colin King <colin.king@canonical.com> wrote:
>>
>> From: Colin Ian King <colin.king@canonical.com>
>>
>> Currently the kfree of pointer qfprom_cdata is kfreeing an
>> error value that has been cast to a pointer rather than a
>> valid address.  Fix this by removing the kfree.
> 
> Hmm, we just added this to other places[1] as a fix for mem leaks
> using the nvmem api. >
This patch has nothing to do with the memleak fix.
> I think we need to fix up the qfprom_read wrapper. Srini?

not sure how we can fix that, as the pointer returned from read is needs 
to be freed by the caller after its done with it!

--srini


> 
> [1] https://lore.kernel.org/stable/20191010083616.685532154@linuxfoundation.org/

> 
>> Fixes: 95ededc17e4e ("thermal: qcom: tsens-v1: Add support for MSM8956 and MSM8976")
>> Signed-off-by: Colin Ian King <colin.king@canonical.com>
>> ---
>>   drivers/thermal/qcom/tsens-v1.c | 4 +---
>>   1 file changed, 1 insertion(+), 3 deletions(-)
>>
>> diff --git a/drivers/thermal/qcom/tsens-v1.c b/drivers/thermal/qcom/tsens-v1.c
>> index 2d1077b64887..bd2ddb684a45 100644
>> --- a/drivers/thermal/qcom/tsens-v1.c
>> +++ b/drivers/thermal/qcom/tsens-v1.c
>> @@ -240,10 +240,8 @@ static int calibrate_8976(struct tsens_priv *priv)
>>          u32 *qfprom_cdata;
>>
>>          qfprom_cdata = (u32 *)qfprom_read(priv->dev, "calib");
>> -       if (IS_ERR(qfprom_cdata)) {
>> -               kfree(qfprom_cdata);
>> +       if (IS_ERR(qfprom_cdata))
>>                  return PTR_ERR(qfprom_cdata);
>> -       }
>>
>>          mode = (qfprom_cdata[4] & MSM8976_CAL_SEL_MASK);
>>          dev_dbg(priv->dev, "calibration mode is %d\n", mode);
>> --
>> 2.20.1
>>