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Subject: Re: [PATCH v1] soc: bcm: Check for NULL return of devm_kzalloc()
To:     Sergey Shtylyov <s.shtylyov@omp.ru>
References: <1648110940-4684-1-git-send-email-unSimple1993@163.com>
 <0f5e77e9-3c2c-396d-636b-1b7153007fe5@omp.ru>
Cc:     bcm-kernel-feedback-list@broadcom.com, f.fainelli@gmail.com,
        linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org
From:   QintaoShen <unSimple1993@163.com>
Message-ID: <37a63518-5d68-fddf-a10b-1aad2c2302c1@163.com>
Date:   Mon, 28 Mar 2022 12:13:40 +0800
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OK. Here is the new version.

Signed-off-by: QintaoShen <unSimple1993@163.com>
---
  drivers/soc/bcm/bcm63xx/bcm-pmb.c | 3 +++
  1 file changed, 3 insertions(+)

diff --git a/drivers/soc/bcm/bcm63xx/bcm-pmb.c 
b/drivers/soc/bcm/bcm63xx/bcm-pmb.c
index 7bbe46e..cc20ffb 100644
--- a/drivers/soc/bcm/bcm63xx/bcm-pmb.c
+++ b/drivers/soc/bcm/bcm63xx/bcm-pmb.c
@@ -312,6 +312,9 @@ static int bcm_pmb_probe(struct platform_device *pdev)
      for (e = table; e->name; e++) {
          struct bcm_pmb_pm_domain *pd = devm_kzalloc(dev, sizeof(*pd), 
GFP_KERNEL);

+        if (!pd)
+            return -ENOMEM;
+
          pd->pmb = pmb;
          pd->data = e;
          pd->genpd.name = e->name;
-- 
2.7.4

在 2022/3/25 下午5:02, Sergey Shtylyov 写道:
> Hello!
>
>     s/return/result/ in the subject.
>
> On 3/24/22 11:35 AM, QintaoShen wrote:
>
>> As the potential failuer of allocation, devm_kzalloc() may return NULL.
>> Then the 'pd->pmb' and the follow lines of code may bring null pointer dereference.
>     Following.
>
>> Therefore, it is better to check the return value of devm_kzalloc() to avoid this confusion.
>>
>> Signed-off-by: QintaoShen <unSimple1993@163.com>
>> ---
>>   drivers/soc/bcm/bcm63xx/bcm-pmb.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/soc/bcm/bcm63xx/bcm-pmb.c b/drivers/soc/bcm/bcm63xx/bcm-pmb.c
>> index 7bbe46e..55bf389 100644
>> --- a/drivers/soc/bcm/bcm63xx/bcm-pmb.c
>> +++ b/drivers/soc/bcm/bcm63xx/bcm-pmb.c
>> @@ -311,6 +311,8 @@ static int bcm_pmb_probe(struct platform_device *pdev)
>>   
>>   	for (e = table; e->name; e++) {
>>   		struct bcm_pmb_pm_domain *pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
>     Please keep an empty line after declaration.
>
>> +		if (!pd)
>> +			return -ENOMEM;
>>   
>>   		pd->pmb = pmb;
>>   		pd->data = e;
> MBR, Sergey