Linux Virtualization - Jul 2019 - [PATCH v2] virtio-mmio: add error check for platform_get_irq

in vm_find_vqs() irq has a wrong type
so, in case of no IRQ resource defined,
wrong parameter will be passed to request_irq()

Signed-off-by: Ihor Matushchak <ihor.matushchak at foobox.net>
---
Changes in v2:
Don't overwrite error code value.

 drivers/virtio/virtio_mmio.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index f363fbeb5ab0..e09edb5c5e06 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -463,9 +463,14 @@ static int vm_find_vqs(struct virtio_device *vdev, unsigned
nvqs,
 		       struct irq_affinity *desc)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
-	unsigned int irq = platform_get_irq(vm_dev->pdev, 0);
+	int irq = platform_get_irq(vm_dev->pdev, 0);
 	int i, err, queue_idx = 0;
 
+	if (irq < 0) {
+		dev_err(&vdev->dev, "Cannot get IRQ resource\n");
+		return irq;
+	}
+
 	err = request_irq(irq, vm_interrupt, IRQF_SHARED,
 			dev_name(&vdev->dev), vm_dev);
 	if (err)
-- 
2.17.1

Quoting Ihor Matushchak (2019-07-02 17:48:18)
> in vm_find_vqs() irq has a wrong type
> so, in case of no IRQ resource defined,
> wrong parameter will be passed to request_irq()
> 
> Signed-off-by: Ihor Matushchak <ihor.matushchak at foobox.net>

Reviewed-by: Ivan T. Ivanov <iivanov.xz at gmail.com>

Thanks!
> ---
> Changes in v2:
> Don't overwrite error code value.
> 
>  drivers/virtio/virtio_mmio.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
> index f363fbeb5ab0..e09edb5c5e06 100644
> --- a/drivers/virtio/virtio_mmio.c
> +++ b/drivers/virtio/virtio_mmio.c
> @@ -463,9 +463,14 @@ static int vm_find_vqs(struct virtio_device *vdev,
unsigned nvqs,
>                        struct irq_affinity *desc)
>  {
>         struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
> -       unsigned int irq = platform_get_irq(vm_dev->pdev, 0);
> +       int irq = platform_get_irq(vm_dev->pdev, 0);
>         int i, err, queue_idx = 0;
>  
> +       if (irq < 0) {
> +               dev_err(&vdev->dev, "Cannot get IRQ
resource\n");
> +               return irq;
> +       }
> +
>         err = request_irq(irq, vm_interrupt, IRQF_SHARED,
>                         dev_name(&vdev->dev), vm_dev);
>         if (err)
> -- 
> 2.17.1
>

On Tue, Jul 02, 2019 at 05:48:18PM +0300, Ihor Matushchak
wrote:
> in vm_find_vqs() irq has a wrong type
> so, in case of no IRQ resource defined,
> wrong parameter will be passed to request_irq()
> 
> Signed-off-by: Ihor Matushchak <ihor.matushchak at foobox.net>
Thanks!
pls don't make v2 a response to v1 in the future though.
> ---
> Changes in v2:
> Don't overwrite error code value.
> 
>  drivers/virtio/virtio_mmio.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
> index f363fbeb5ab0..e09edb5c5e06 100644
> --- a/drivers/virtio/virtio_mmio.c
> +++ b/drivers/virtio/virtio_mmio.c
> @@ -463,9 +463,14 @@ static int vm_find_vqs(struct virtio_device *vdev,
unsigned nvqs,
>  		       struct irq_affinity *desc)
>  {
>  	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
> -	unsigned int irq = platform_get_irq(vm_dev->pdev, 0);
> +	int irq = platform_get_irq(vm_dev->pdev, 0);
>  	int i, err, queue_idx = 0;
>  
> +	if (irq < 0) {
> +		dev_err(&vdev->dev, "Cannot get IRQ resource\n");
> +		return irq;
> +	}
> +
>  	err = request_irq(irq, vm_interrupt, IRQF_SHARED,
>  			dev_name(&vdev->dev), vm_dev);
>  	if (err)
> -- 
> 2.17.1