[PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Hanjun Guo]

In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
although the chances are small, I think it should be fixed.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
---
 drivers/acpi/processor_driver.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index bec717f..dd64f23 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -579,6 +579,10 @@ static int __cpuinit acpi_processor_add(struct acpi_device
*device)
        per_cpu(processors, pr->id) = pr;

        dev = get_cpu_device(pr->id);
+       if (!dev) {
+               result = -ENODEV;
+               goto err_clear_processor;
+       }
        if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
                result = -EFAULT;
                goto err_clear_processor;
-- 
1.7.1

Re: [PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Rafael J. Wysocki]

On Thursday, May 23, 2013 08:44:26 PM Hanjun Guo wrote:
> In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
> although the chances are small, I think it should be fixed.
> 
> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>

This patch isn't necessary any more after the changes queued up for 3.11
in the acpi-hotplug branch of the linux-pm.git tree.

Thanks,
Rafael


> ---
>  drivers/acpi/processor_driver.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
> index bec717f..dd64f23 100644
> --- a/drivers/acpi/processor_driver.c
> +++ b/drivers/acpi/processor_driver.c
> @@ -579,6 +579,10 @@ static int __cpuinit acpi_processor_add(struct acpi_device
> *device)
>         per_cpu(processors, pr->id) = pr;
> 
>         dev = get_cpu_device(pr->id);
> +       if (!dev) {
> +               result = -ENODEV;
> +               goto err_clear_processor;
> +       }
>         if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
>                 result = -EFAULT;
>                 goto err_clear_processor;
> 
-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.

Re: [PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Hanjun Guo]

On 2013-5-29 7:30, Rafael J. Wysocki wrote:
> On Thursday, May 23, 2013 08:44:26 PM Hanjun Guo wrote:
>> In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
>> although the chances are small, I think it should be fixed.
>>
>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> 
> This patch isn't necessary any more after the changes queued up for 3.11
> in the acpi-hotplug branch of the linux-pm.git tree.

Ok, I noticed your patch set, just drop my patch.

Thanks
Hanjun

> 
> Thanks,
> Rafael
> 
> 
>> ---
>>  drivers/acpi/processor_driver.c |    4 ++++
>>  1 files changed, 4 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
>> index bec717f..dd64f23 100644
>> --- a/drivers/acpi/processor_driver.c
>> +++ b/drivers/acpi/processor_driver.c
>> @@ -579,6 +579,10 @@ static int __cpuinit acpi_processor_add(struct acpi_device
>> *device)
>>         per_cpu(processors, pr->id) = pr;
>>
>>         dev = get_cpu_device(pr->id);
>> +       if (!dev) {
>> +               result = -ENODEV;
>> +               goto err_clear_processor;
>> +       }
>>         if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
>>                 result = -EFAULT;
>>                 goto err_clear_processor;
>>

Re: [PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Martin Mokrejs]

Hanjun Guo wrote:
> On 2013-5-29 7:30, Rafael J. Wysocki wrote:
>> On Thursday, May 23, 2013 08:44:26 PM Hanjun Guo wrote:
>>> In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
>>> although the chances are small, I think it should be fixed.
>>>
>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>>
>> This patch isn't necessary any more after the changes queued up for 3.11
>> in the acpi-hotplug branch of the linux-pm.git tree.
> 
> Ok, I noticed your patch set, just drop my patch.

But shouldn't this go to stable at least? I checked linux-3.9.4
and it applies fine. Whether this is relevant for other stable
series I will leave up to somebody else. ;)
Martin

> 
> Thanks
> Hanjun
> 
>>
>> Thanks,
>> Rafael
>>
>>
>>> ---
>>>  drivers/acpi/processor_driver.c |    4 ++++
>>>  1 files changed, 4 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
>>> index bec717f..dd64f23 100644
>>> --- a/drivers/acpi/processor_driver.c
>>> +++ b/drivers/acpi/processor_driver.c
>>> @@ -579,6 +579,10 @@ static int __cpuinit acpi_processor_add(struct acpi_device
>>> *device)
>>>         per_cpu(processors, pr->id) = pr;
>>>
>>>         dev = get_cpu_device(pr->id);
>>> +       if (!dev) {
>>> +               result = -ENODEV;
>>> +               goto err_clear_processor;
>>> +       }
>>>         if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
>>>                 result = -EFAULT;
>>>                 goto err_clear_processor;
>>>
> 
> --
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> 
> 

Re: [PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Hanjun Guo]

On 2013-5-29 19:07, Martin Mokrejs wrote:
> Hanjun Guo wrote:
>> On 2013-5-29 7:30, Rafael J. Wysocki wrote:
>>> On Thursday, May 23, 2013 08:44:26 PM Hanjun Guo wrote:
>>>> In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
>>>> although the chances are small, I think it should be fixed.
>>>>
>>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>>>
>>> This patch isn't necessary any more after the changes queued up for 3.11
>>> in the acpi-hotplug branch of the linux-pm.git tree.
>>
>> Ok, I noticed your patch set, just drop my patch.
> 
> But shouldn't this go to stable at least? I checked linux-3.9.4
> and it applies fine. Whether this is relevant for other stable
> series I will leave up to somebody else. ;)

Hi Rafeal,

What's your opinion on Martin's suggestion?

Thanks
Hanjun

> Martin

Re: [PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Rafael J. Wysocki]

On Thursday, May 30, 2013 10:29:54 AM Hanjun Guo wrote:
> On 2013-5-29 19:07, Martin Mokrejs wrote:
> > Hanjun Guo wrote:
> >> On 2013-5-29 7:30, Rafael J. Wysocki wrote:
> >>> On Thursday, May 23, 2013 08:44:26 PM Hanjun Guo wrote:
> >>>> In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
> >>>> although the chances are small, I think it should be fixed.
> >>>>
> >>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> >>>
> >>> This patch isn't necessary any more after the changes queued up for 3.11
> >>> in the acpi-hotplug branch of the linux-pm.git tree.
> >>
> >> Ok, I noticed your patch set, just drop my patch.
> > 
> > But shouldn't this go to stable at least? I checked linux-3.9.4
> > and it applies fine. Whether this is relevant for other stable
> > series I will leave up to somebody else. ;)
> 
> Hi Rafeal,
> 
> What's your opinion on Martin's suggestion?

Well, this is kind of hard to say.  We generally don't apply patches to -stable
that don't have mainline counterparts.

Greg, I wonder what your opinion is?

Rafael


-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.

Re: [PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Greg Kroah-Hartman]

On Thu, May 30, 2013 at 03:57:58PM +0200, Rafael J. Wysocki wrote:
> On Thursday, May 30, 2013 10:29:54 AM Hanjun Guo wrote:
> > On 2013-5-29 19:07, Martin Mokrejs wrote:
> > > Hanjun Guo wrote:
> > >> On 2013-5-29 7:30, Rafael J. Wysocki wrote:
> > >>> On Thursday, May 23, 2013 08:44:26 PM Hanjun Guo wrote:
> > >>>> In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
> > >>>> although the chances are small, I think it should be fixed.
> > >>>>
> > >>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> > >>>
> > >>> This patch isn't necessary any more after the changes queued up for 3.11
> > >>> in the acpi-hotplug branch of the linux-pm.git tree.
> > >>
> > >> Ok, I noticed your patch set, just drop my patch.
> > > 
> > > But shouldn't this go to stable at least? I checked linux-3.9.4
> > > and it applies fine. Whether this is relevant for other stable
> > > series I will leave up to somebody else. ;)
> > 
> > Hi Rafeal,
> > 
> > What's your opinion on Martin's suggestion?
> 
> Well, this is kind of hard to say.  We generally don't apply patches to -stable
> that don't have mainline counterparts.
> 
> Greg, I wonder what your opinion is?

We do not apply patches to -stable that are not in Linus's tree, unless
there is no problem in Linus's tree due to a major rewrite of the code,
and it has been confirmed that the same problem isn't there.

thanks,

greg k-h

Re: [PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Hanjun Guo]

[-- Attachment #1: Type: text/plain, Size: 1677 bytes --]

On 2013-5-31 6:25, Greg Kroah-Hartman wrote:
> On Thu, May 30, 2013 at 03:57:58PM +0200, Rafael J. Wysocki wrote:
>> On Thursday, May 30, 2013 10:29:54 AM Hanjun Guo wrote:
>>> On 2013-5-29 19:07, Martin Mokrejs wrote:
>>>> Hanjun Guo wrote:
>>>>> On 2013-5-29 7:30, Rafael J. Wysocki wrote:
>>>>>> On Thursday, May 23, 2013 08:44:26 PM Hanjun Guo wrote:
>>>>>>> In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
>>>>>>> although the chances are small, I think it should be fixed.
>>>>>>>
>>>>>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>>>>>>
>>>>>> This patch isn't necessary any more after the changes queued up for 3.11
>>>>>> in the acpi-hotplug branch of the linux-pm.git tree.
>>>>>
>>>>> Ok, I noticed your patch set, just drop my patch.
>>>>
>>>> But shouldn't this go to stable at least? I checked linux-3.9.4
>>>> and it applies fine. Whether this is relevant for other stable
>>>> series I will leave up to somebody else. ;)
>>>
>>> Hi Rafeal,
>>>
>>> What's your opinion on Martin's suggestion?
>>
>> Well, this is kind of hard to say.  We generally don't apply patches to -stable
>> that don't have mainline counterparts.
>>
>> Greg, I wonder what your opinion is?
> 
> We do not apply patches to -stable that are not in Linus's tree, unless
> there is no problem in Linus's tree due to a major rewrite of the code,
> and it has been confirmed that the same problem isn't there.

Hi Rafael,

I found that the problem is still there in your acpi-hotplug tree, sorry for
I didn't noticed early. I made a patch for this again, I hope it will make
sense to you.

The patch is attached, based on your acpi-hotplug tree.

Thanks
Hanjun




[-- Attachment #2: 0001-ACPI-processor-Fix-potential-NULL-pointer-dereferenc.patch --]
[-- Type: text/plain, Size: 1085 bytes --]

>From 975e30f5906a883e533e4226d8eca1c449c7366b Mon Sep 17 00:00:00 2001
From: Hanjun Guo <hanjun.guo@linaro.org>
Date: Fri, 31 May 2013 11:36:08 +0800
Subject: [PATCH 1/1] ACPI / processor: Fix potential NULL pointer dereference
 in acpi_processor_add()

In acpi_processor_add(), get_cpu_device() will return NULL in some cases,
and ACPI_HANDLE_SET() just use the return dev directly, this will case a
potential NULL pointer dereference, fix it.

Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
---
 drivers/acpi/acpi_processor.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 587d2af..4466b36 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -389,6 +389,11 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device,
 	per_cpu(processor_device_array, pr->id) = device;
 
 	dev = get_cpu_device(pr->id);
+	if (!dev) {
+		result = -ENODEV;
+		goto err;
+	}
+
 	ACPI_HANDLE_SET(dev, pr->handle);
 	result = acpi_bind_one(dev, NULL);
 	if (result)
-- 
1.7.9.5

Re: [PATCH] ACPI: Fix potential NULL pointer dereference in acpi_processor_add()

[Rafael J. Wysocki]

On Friday, May 31, 2013 11:58:49 AM Hanjun Guo wrote:
> On 2013-5-31 6:25, Greg Kroah-Hartman wrote:
> > On Thu, May 30, 2013 at 03:57:58PM +0200, Rafael J. Wysocki wrote:
> >> On Thursday, May 30, 2013 10:29:54 AM Hanjun Guo wrote:
> >>> On 2013-5-29 19:07, Martin Mokrejs wrote:
> >>>> Hanjun Guo wrote:
> >>>>> On 2013-5-29 7:30, Rafael J. Wysocki wrote:
> >>>>>> On Thursday, May 23, 2013 08:44:26 PM Hanjun Guo wrote:
> >>>>>>> In acpi_processor_add(), get_cpu_device() will return NULL sometimes,
> >>>>>>> although the chances are small, I think it should be fixed.
> >>>>>>>
> >>>>>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> >>>>>>
> >>>>>> This patch isn't necessary any more after the changes queued up for 3.11
> >>>>>> in the acpi-hotplug branch of the linux-pm.git tree.
> >>>>>
> >>>>> Ok, I noticed your patch set, just drop my patch.
> >>>>
> >>>> But shouldn't this go to stable at least? I checked linux-3.9.4
> >>>> and it applies fine. Whether this is relevant for other stable
> >>>> series I will leave up to somebody else. ;)
> >>>
> >>> Hi Rafeal,
> >>>
> >>> What's your opinion on Martin's suggestion?
> >>
> >> Well, this is kind of hard to say.  We generally don't apply patches to -stable
> >> that don't have mainline counterparts.
> >>
> >> Greg, I wonder what your opinion is?
> > 
> > We do not apply patches to -stable that are not in Linus's tree, unless
> > there is no problem in Linus's tree due to a major rewrite of the code,
> > and it has been confirmed that the same problem isn't there.
> 
> Hi Rafael,
> 
> I found that the problem is still there in your acpi-hotplug tree, sorry for
> I didn't noticed early. I made a patch for this again, I hope it will make
> sense to you.
> 
> The patch is attached, based on your acpi-hotplug tree.

OK, thanks!

Rafael


-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.