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 <[email protected]>
---
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);
+ 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:
devm_kfree(kdev->dev, pool);
return ERR_PTR(ret);
}
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 <[email protected]>
> ---
> 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);
> + 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:
> devm_kfree(kdev->dev, pool);
> return ERR_PTR(ret);
> }
Can anyone look into this patch?
Thanks
Gen
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 <[email protected]>
>> ---
>> 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...
On Tue, Jun 11, 2019 at 10:54:15AM +0100, Marc Zyngier wrote:
> Hi Gen,
>
> No idea why I'm being cc'd on this but hey... ;-)
I copied email address ftom thid commit:-)
https://github.com/torvalds/linux/commit/832ad0e3da4510fd17f98804abe512ea9a747035#diff-f2a24befc247191f4b81af93e9336785
>
> 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 <[email protected]>
> >> ---
> >> 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.
Thanks for your comments.
>
> >> + 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.
Sure, better not to add redundant codes.
>
> >> 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.
That sounds reasonable. This patch just fixes a *theoretical* bug.
Thanks
Gen
>
> Thanks,
>
> M.
> --
> Jazz is not dead. It just smells funny...
On 6/11/19 3:08 AM, Gen Zhang wrote:
> On Tue, Jun 11, 2019 at 10:54:15AM +0100, Marc Zyngier wrote:
>> Hi Gen,
>>
>> No idea why I'm being cc'd on this but hey... ;-)
> I copied email address ftom thid commit:-)
> https://github.com/torvalds/linux/commit/832ad0e3da4510fd17f98804abe512ea9a747035#diff-f2a24befc247191f4b81af93e9336785
>>
>> 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 <[email protected]>
>>>> ---
>>>> 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.
> Thanks for your comments.
>>
>>>> + 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.
> Sure, better not to add redundant codes.
>>
>>>> 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.
> That sounds reasonable. This patch just fixes a *theoretical* bug.
>
Not even theoretical bug.