[PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Ard Biesheuvel]

Registering an IRQ requires the string buffer containing the name to
remain allocated, as the name is not copied into another buffer.

So let's add a irq_name field to the data struct instead, which is
guaranteed to have the appropriate lifetime.

Cc: Thara Gopinath <thara.gopinath@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Andy Gross <agross@kernel.org>
Cc: linux-arm-msm@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
I'm not following msm development closely, so apologies if this was
already fixed, or if this is not based on the right tree.

This fixes a crash on my Yoga C630 when reading /proc/interrupts.

 drivers/cpufreq/qcom-cpufreq-hw.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
index 3cc27d9e2ed1..6613228fe68c 100644
--- a/drivers/cpufreq/qcom-cpufreq-hw.c
+++ b/drivers/cpufreq/qcom-cpufreq-hw.c
@@ -44,6 +44,7 @@ struct qcom_cpufreq_data {
 	/* Lock to synchronize between de-init sequence and re-starting LMh polling/interrupts */
 	spinlock_t throttle_lock;
 	int throttle_irq;
+	char irq_name[15];
 	bool cancel_throttle;
 };
 
@@ -371,7 +372,6 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
 {
 	struct qcom_cpufreq_data *data = policy->driver_data;
 	struct platform_device *pdev = cpufreq_get_driver_data();
-	char irq_name[15];
 	int ret;
 
 	/*
@@ -388,11 +388,11 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
 	spin_lock_init(&data->throttle_lock);
 	INIT_DEFERRABLE_WORK(&data->throttle_work, qcom_lmh_dcvs_poll);
 
-	snprintf(irq_name, sizeof(irq_name), "dcvsh-irq-%u", policy->cpu);
+	snprintf(data->irq_name, sizeof(data->irq_name), "dcvsh-irq-%u", policy->cpu);
 	ret = request_threaded_irq(data->throttle_irq, NULL, qcom_lmh_dcvs_handle_irq,
-				   IRQF_ONESHOT, irq_name, data);
+				   IRQF_ONESHOT, data->irq_name, data);
 	if (ret) {
-		dev_err(&pdev->dev, "Error registering %s: %d\n", irq_name, ret);
+		dev_err(&pdev->dev, "Error registering %s: %d\n", data->irq_name, ret);
 		return 0;
 	}
 
-- 
2.30.2

[PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Ard Biesheuvel]

Registering an IRQ requires the string buffer containing the name to
remain allocated, as the name is not copied into another buffer.

So let's add a irq_name field to the data struct instead, which is
guaranteed to have the appropriate lifetime.

Cc: Thara Gopinath <thara.gopinath@linaro.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Andy Gross <agross@kernel.org>
Cc: linux-arm-msm@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
I'm not following msm development closely, so apologies if this was
already fixed, or if this is not based on the right tree.

This fixes a crash on my Yoga C630 when reading /proc/interrupts.

 drivers/cpufreq/qcom-cpufreq-hw.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
index 3cc27d9e2ed1..6613228fe68c 100644
--- a/drivers/cpufreq/qcom-cpufreq-hw.c
+++ b/drivers/cpufreq/qcom-cpufreq-hw.c
@@ -44,6 +44,7 @@ struct qcom_cpufreq_data {
 	/* Lock to synchronize between de-init sequence and re-starting LMh polling/interrupts */
 	spinlock_t throttle_lock;
 	int throttle_irq;
+	char irq_name[15];
 	bool cancel_throttle;
 };
 
@@ -371,7 +372,6 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
 {
 	struct qcom_cpufreq_data *data = policy->driver_data;
 	struct platform_device *pdev = cpufreq_get_driver_data();
-	char irq_name[15];
 	int ret;
 
 	/*
@@ -388,11 +388,11 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
 	spin_lock_init(&data->throttle_lock);
 	INIT_DEFERRABLE_WORK(&data->throttle_work, qcom_lmh_dcvs_poll);
 
-	snprintf(irq_name, sizeof(irq_name), "dcvsh-irq-%u", policy->cpu);
+	snprintf(data->irq_name, sizeof(data->irq_name), "dcvsh-irq-%u", policy->cpu);
 	ret = request_threaded_irq(data->throttle_irq, NULL, qcom_lmh_dcvs_handle_irq,
-				   IRQF_ONESHOT, irq_name, data);
+				   IRQF_ONESHOT, data->irq_name, data);
 	if (ret) {
-		dev_err(&pdev->dev, "Error registering %s: %d\n", irq_name, ret);
+		dev_err(&pdev->dev, "Error registering %s: %d\n", data->irq_name, ret);
 		return 0;
 	}
 
-- 
2.30.2


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Steev Klimaszewski]

On 9/1/21 3:47 AM, Ard Biesheuvel wrote:
> Registering an IRQ requires the string buffer containing the name to
> remain allocated, as the name is not copied into another buffer.
>
> So let's add a irq_name field to the data struct instead, which is
> guaranteed to have the appropriate lifetime.
>
> Cc: Thara Gopinath <thara.gopinath@linaro.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Andy Gross <agross@kernel.org>
> Cc: linux-arm-msm@vger.kernel.org
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> ---
> I'm not following msm development closely, so apologies if this was
> already fixed, or if this is not based on the right tree.
>
> This fixes a crash on my Yoga C630 when reading /proc/interrupts.
>
>  drivers/cpufreq/qcom-cpufreq-hw.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> index 3cc27d9e2ed1..6613228fe68c 100644
> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> @@ -44,6 +44,7 @@ struct qcom_cpufreq_data {
>  	/* Lock to synchronize between de-init sequence and re-starting LMh polling/interrupts */
>  	spinlock_t throttle_lock;
>  	int throttle_irq;
> +	char irq_name[15];
>  	bool cancel_throttle;
>  };
>  
> @@ -371,7 +372,6 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
>  {
>  	struct qcom_cpufreq_data *data = policy->driver_data;
>  	struct platform_device *pdev = cpufreq_get_driver_data();
> -	char irq_name[15];
>  	int ret;
>  
>  	/*
> @@ -388,11 +388,11 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
>  	spin_lock_init(&data->throttle_lock);
>  	INIT_DEFERRABLE_WORK(&data->throttle_work, qcom_lmh_dcvs_poll);
>  
> -	snprintf(irq_name, sizeof(irq_name), "dcvsh-irq-%u", policy->cpu);
> +	snprintf(data->irq_name, sizeof(data->irq_name), "dcvsh-irq-%u", policy->cpu);
>  	ret = request_threaded_irq(data->throttle_irq, NULL, qcom_lmh_dcvs_handle_irq,
> -				   IRQF_ONESHOT, irq_name, data);
> +				   IRQF_ONESHOT, data->irq_name, data);
>  	if (ret) {
> -		dev_err(&pdev->dev, "Error registering %s: %d\n", irq_name, ret);
> +		dev_err(&pdev->dev, "Error registering %s: %d\n", data->irq_name, ret);
>  		return 0;
>  	}
>  

I haven't experienced the crash here, but I also tested the patch on my
C630, and still don't see the issue so, if you want:

Tested-By: Steev Klimaszewski <steev@kali.org>

Re: [PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Steev Klimaszewski]

On 9/1/21 3:47 AM, Ard Biesheuvel wrote:
> Registering an IRQ requires the string buffer containing the name to
> remain allocated, as the name is not copied into another buffer.
>
> So let's add a irq_name field to the data struct instead, which is
> guaranteed to have the appropriate lifetime.
>
> Cc: Thara Gopinath <thara.gopinath@linaro.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Andy Gross <agross@kernel.org>
> Cc: linux-arm-msm@vger.kernel.org
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> ---
> I'm not following msm development closely, so apologies if this was
> already fixed, or if this is not based on the right tree.
>
> This fixes a crash on my Yoga C630 when reading /proc/interrupts.
>
>  drivers/cpufreq/qcom-cpufreq-hw.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> index 3cc27d9e2ed1..6613228fe68c 100644
> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> @@ -44,6 +44,7 @@ struct qcom_cpufreq_data {
>  	/* Lock to synchronize between de-init sequence and re-starting LMh polling/interrupts */
>  	spinlock_t throttle_lock;
>  	int throttle_irq;
> +	char irq_name[15];
>  	bool cancel_throttle;
>  };
>  
> @@ -371,7 +372,6 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
>  {
>  	struct qcom_cpufreq_data *data = policy->driver_data;
>  	struct platform_device *pdev = cpufreq_get_driver_data();
> -	char irq_name[15];
>  	int ret;
>  
>  	/*
> @@ -388,11 +388,11 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
>  	spin_lock_init(&data->throttle_lock);
>  	INIT_DEFERRABLE_WORK(&data->throttle_work, qcom_lmh_dcvs_poll);
>  
> -	snprintf(irq_name, sizeof(irq_name), "dcvsh-irq-%u", policy->cpu);
> +	snprintf(data->irq_name, sizeof(data->irq_name), "dcvsh-irq-%u", policy->cpu);
>  	ret = request_threaded_irq(data->throttle_irq, NULL, qcom_lmh_dcvs_handle_irq,
> -				   IRQF_ONESHOT, irq_name, data);
> +				   IRQF_ONESHOT, data->irq_name, data);
>  	if (ret) {
> -		dev_err(&pdev->dev, "Error registering %s: %d\n", irq_name, ret);
> +		dev_err(&pdev->dev, "Error registering %s: %d\n", data->irq_name, ret);
>  		return 0;
>  	}
>  

I haven't experienced the crash here, but I also tested the patch on my
C630, and still don't see the issue so, if you want:

Tested-By: Steev Klimaszewski <steev@kali.org>


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Thara Gopinath]

On 9/1/21 4:47 AM, Ard Biesheuvel wrote:
> Registering an IRQ requires the string buffer containing the name to
> remain allocated, as the name is not copied into another buffer.
> 
> So let's add a irq_name field to the data struct instead, which is
> guaranteed to have the appropriate lifetime.
> 
> Cc: Thara Gopinath <thara.gopinath@linaro.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Andy Gross <agross@kernel.org>
> Cc: linux-arm-msm@vger.kernel.org
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Thanks for the fix.

Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>

-- 
Warm Regards
Thara (She/Her/Hers)

> ---
> I'm not following msm development closely, so apologies if this was
> already fixed, or if this is not based on the right tree.
> 
> This fixes a crash on my Yoga C630 when reading /proc/interrupts.
> 
>   drivers/cpufreq/qcom-cpufreq-hw.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> index 3cc27d9e2ed1..6613228fe68c 100644
> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> @@ -44,6 +44,7 @@ struct qcom_cpufreq_data {
>   	/* Lock to synchronize between de-init sequence and re-starting LMh polling/interrupts */
>   	spinlock_t throttle_lock;
>   	int throttle_irq;
> +	char irq_name[15];
>   	bool cancel_throttle;
>   };
>   
> @@ -371,7 +372,6 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
>   {
>   	struct qcom_cpufreq_data *data = policy->driver_data;
>   	struct platform_device *pdev = cpufreq_get_driver_data();
> -	char irq_name[15];
>   	int ret;
>   
>   	/*
> @@ -388,11 +388,11 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
>   	spin_lock_init(&data->throttle_lock);
>   	INIT_DEFERRABLE_WORK(&data->throttle_work, qcom_lmh_dcvs_poll);
>   
> -	snprintf(irq_name, sizeof(irq_name), "dcvsh-irq-%u", policy->cpu);
> +	snprintf(data->irq_name, sizeof(data->irq_name), "dcvsh-irq-%u", policy->cpu);
>   	ret = request_threaded_irq(data->throttle_irq, NULL, qcom_lmh_dcvs_handle_irq,
> -				   IRQF_ONESHOT, irq_name, data);
> +				   IRQF_ONESHOT, data->irq_name, data);
>   	if (ret) {
> -		dev_err(&pdev->dev, "Error registering %s: %d\n", irq_name, ret);
> +		dev_err(&pdev->dev, "Error registering %s: %d\n", data->irq_name, ret);
>   		return 0;
>   	}
>   
> 

Re: [PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Thara Gopinath]

On 9/1/21 4:47 AM, Ard Biesheuvel wrote:
> Registering an IRQ requires the string buffer containing the name to
> remain allocated, as the name is not copied into another buffer.
> 
> So let's add a irq_name field to the data struct instead, which is
> guaranteed to have the appropriate lifetime.
> 
> Cc: Thara Gopinath <thara.gopinath@linaro.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Cc: Andy Gross <agross@kernel.org>
> Cc: linux-arm-msm@vger.kernel.org
> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Thanks for the fix.

Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>

-- 
Warm Regards
Thara (She/Her/Hers)

> ---
> I'm not following msm development closely, so apologies if this was
> already fixed, or if this is not based on the right tree.
> 
> This fixes a crash on my Yoga C630 when reading /proc/interrupts.
> 
>   drivers/cpufreq/qcom-cpufreq-hw.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> index 3cc27d9e2ed1..6613228fe68c 100644
> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> @@ -44,6 +44,7 @@ struct qcom_cpufreq_data {
>   	/* Lock to synchronize between de-init sequence and re-starting LMh polling/interrupts */
>   	spinlock_t throttle_lock;
>   	int throttle_irq;
> +	char irq_name[15];
>   	bool cancel_throttle;
>   };
>   
> @@ -371,7 +372,6 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
>   {
>   	struct qcom_cpufreq_data *data = policy->driver_data;
>   	struct platform_device *pdev = cpufreq_get_driver_data();
> -	char irq_name[15];
>   	int ret;
>   
>   	/*
> @@ -388,11 +388,11 @@ static int qcom_cpufreq_hw_lmh_init(struct cpufreq_policy *policy, int index)
>   	spin_lock_init(&data->throttle_lock);
>   	INIT_DEFERRABLE_WORK(&data->throttle_work, qcom_lmh_dcvs_poll);
>   
> -	snprintf(irq_name, sizeof(irq_name), "dcvsh-irq-%u", policy->cpu);
> +	snprintf(data->irq_name, sizeof(data->irq_name), "dcvsh-irq-%u", policy->cpu);
>   	ret = request_threaded_irq(data->throttle_irq, NULL, qcom_lmh_dcvs_handle_irq,
> -				   IRQF_ONESHOT, irq_name, data);
> +				   IRQF_ONESHOT, data->irq_name, data);
>   	if (ret) {
> -		dev_err(&pdev->dev, "Error registering %s: %d\n", irq_name, ret);
> +		dev_err(&pdev->dev, "Error registering %s: %d\n", data->irq_name, ret);
>   		return 0;
>   	}
>   
> 



_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Loic Poulain]

> On 9/1/21 4:47 AM, Ard Biesheuvel wrote:
> > Registering an IRQ requires the string buffer containing the name to
> > remain allocated, as the name is not copied into another buffer.
> >
> > So let's add a irq_name field to the data struct instead, which is
> > guaranteed to have the appropriate lifetime.
> >
> > Cc: Thara Gopinath <thara.gopinath@linaro.org>
> > Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> > Cc: Andy Gross <agross@kernel.org>
> > Cc: linux-arm-msm@vger.kernel.org
> > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
>
> Thanks for the fix.
>
> Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>

Seems this patch has been overlooked. Would it be possible to resubmit
it with a 'Fixes' tag?

Regards,
Loic

Re: [PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Loic Poulain]

> On 9/1/21 4:47 AM, Ard Biesheuvel wrote:
> > Registering an IRQ requires the string buffer containing the name to
> > remain allocated, as the name is not copied into another buffer.
> >
> > So let's add a irq_name field to the data struct instead, which is
> > guaranteed to have the appropriate lifetime.
> >
> > Cc: Thara Gopinath <thara.gopinath@linaro.org>
> > Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> > Cc: Andy Gross <agross@kernel.org>
> > Cc: linux-arm-msm@vger.kernel.org
> > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
>
> Thanks for the fix.
>
> Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>

Seems this patch has been overlooked. Would it be possible to resubmit
it with a 'Fixes' tag?

Regards,
Loic

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Bjorn Andersson]

On Mon 20 Dec 02:12 PST 2021, Loic Poulain wrote:

> > On 9/1/21 4:47 AM, Ard Biesheuvel wrote:
> > > Registering an IRQ requires the string buffer containing the name to
> > > remain allocated, as the name is not copied into another buffer.
> > >
> > > So let's add a irq_name field to the data struct instead, which is
> > > guaranteed to have the appropriate lifetime.
> > >
> > > Cc: Thara Gopinath <thara.gopinath@linaro.org>
> > > Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> > > Cc: Andy Gross <agross@kernel.org>
> > > Cc: linux-arm-msm@vger.kernel.org
> > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> >
> > Thanks for the fix.
> >
> > Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>
> 
> Seems this patch has been overlooked. Would it be possible to resubmit
> it with a 'Fixes' tag?
> 

This was resubmitted by Vladimir and Viresh replied that it's applied,
see:

https://lore.kernel.org/all/20211125065014.phkfugo2wptosrgv@vireshk-i7/

Regards,
Bjorn

Re: [PATCH] cpufreq: qcom-cpufreq-hw: Avoid stack buffer for IRQ name

[Bjorn Andersson]

On Mon 20 Dec 02:12 PST 2021, Loic Poulain wrote:

> > On 9/1/21 4:47 AM, Ard Biesheuvel wrote:
> > > Registering an IRQ requires the string buffer containing the name to
> > > remain allocated, as the name is not copied into another buffer.
> > >
> > > So let's add a irq_name field to the data struct instead, which is
> > > guaranteed to have the appropriate lifetime.
> > >
> > > Cc: Thara Gopinath <thara.gopinath@linaro.org>
> > > Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> > > Cc: Andy Gross <agross@kernel.org>
> > > Cc: linux-arm-msm@vger.kernel.org
> > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
> >
> > Thanks for the fix.
> >
> > Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>
> 
> Seems this patch has been overlooked. Would it be possible to resubmit
> it with a 'Fixes' tag?
> 

This was resubmitted by Vladimir and Viresh replied that it's applied,
see:

https://lore.kernel.org/all/20211125065014.phkfugo2wptosrgv@vireshk-i7/

Regards,
Bjorn

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel