Re: [PATCH] vfio/pci: clean up a type in vfio_pci_ioctl_pci_hot_reset_groups()

From: Alex Williamson
Date: Thu Sep 12 2024 - 16:49:13 EST


On Thu, 12 Sep 2024 11:49:10 +0300
Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:

> The "array_count" value comes from the copy_from_user() in
> vfio_pci_ioctl_pci_hot_reset(). If the user passes a value larger than
> INT_MAX then we'll pass a negative value to kcalloc() which triggers an
> allocation failure and a stack trace.
>
> It's better to make the type unsigned so that if (array_count > count)
> returns -EINVAL instead.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> drivers/vfio/pci/vfio_pci_core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
> index 077d4a2629c8..1ab58da9f38a 100644
> --- a/drivers/vfio/pci/vfio_pci_core.c
> +++ b/drivers/vfio/pci/vfio_pci_core.c
> @@ -1324,7 +1324,7 @@ static int vfio_pci_ioctl_get_pci_hot_reset_info(
>
> static int
> vfio_pci_ioctl_pci_hot_reset_groups(struct vfio_pci_core_device *vdev,
> - int array_count, bool slot,
> + u32 array_count, bool slot,
> struct vfio_pci_hot_reset __user *arg)
> {
> int32_t *group_fds;

Applied to vfio next branch for v6.12. Thanks!

Alex