From: Marc Zyngier <marc.zyngier@arm.com>
To: Gen Zhang <blackgod016574@gmail.com>,
ssantosh@kernel.org, olof@lixom.net
Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] knav_qmss_queue: fix a missing-check bug in knav_pool_create()
Date: Tue, 11 Jun 2019 10:54:15 +0100 [thread overview]
Message-ID: <56a08bd2-6b94-457f-99f7-91ef3fca8804@arm.com> (raw)
In-Reply-To: <20190611093744.GA9783@ubuntu>
Hi Gen,
No idea why I'm being cc'd on this but hey... ;-)
On 11/06/2019 10:37, Gen Zhang wrote:
> On Thu, May 30, 2019 at 11:39:49AM +0800, Gen Zhang wrote:
>> In knav_pool_create(), 'pool->name' is allocated by kstrndup(). It
>> returns NULL when fails. So 'pool->name' should be checked. And free
>> 'pool' when error.
>>
>> Signed-off-by: Gen Zhang <blackgod016574@gmail.com>
>> ---
>> diff --git a/drivers/soc/ti/knav_qmss_queue.c b/drivers/soc/ti/knav_qmss_queue.c
>> index 8b41837..0f8cb28 100644
>> --- a/drivers/soc/ti/knav_qmss_queue.c
>> +++ b/drivers/soc/ti/knav_qmss_queue.c
>> @@ -814,6 +814,12 @@ void *knav_pool_create(const char *name,
>> }
>>
>> pool->name = kstrndup(name, KNAV_NAME_SIZE - 1, GFP_KERNEL);
>> + if (!pool->name) {
>> + dev_err(kdev->dev, "failed to duplicate for pool(%s)\n",
>> + name);
There is no need to output anything, the kernel will be loud enough if
you run out of memory.
>> + ret = -ENOMEM;
>> + goto err_name;
>> + }
>> pool->kdev = kdev;
>> pool->dev = kdev->dev;
>>
>> @@ -864,6 +870,7 @@ void *knav_pool_create(const char *name,
>> mutex_unlock(&knav_dev_lock);
>> err:
>> kfree(pool->name);
>> +err_name:
kfree(NULL) is perfectly valid, there is no need to create a second
label. Just branch to the existing error label.
>> devm_kfree(kdev->dev, pool);
>> return ERR_PTR(ret);
>> }
> Can anyone look into this patch?
>
> Thanks
> Gen
>
The real question is whether this is actually an error at all.
pool->name doesn't seem to be used for anything but debug information,
and the printing code can perfectly accommodate a NULL pointer.
Thanks,
M.
--
Jazz is not dead. It just smells funny...
next prev parent reply other threads:[~2019-06-11 9:54 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-30 3:39 [PATCH] knav_qmss_queue: fix a missing-check bug in knav_pool_create() Gen Zhang
2019-06-11 9:37 ` Gen Zhang
2019-06-11 9:54 ` Marc Zyngier [this message]
2019-06-11 10:08 ` Gen Zhang
2019-06-11 21:10 ` santosh.shilimkar
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