linux-kernel - Re: [RFC 07/14] vfio/nvgrace-egm: Register auxiliary driver ops

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250905133136.GD616306@nvidia.com>
Date: Fri, 5 Sep 2025 10:31:36 -0300
From: Jason Gunthorpe <jgg@...dia.com>
To: ankita@...dia.com
Cc: alex.williamson@...hat.com, yishaih@...dia.com, skolothumtho@...dia.com,
	kevin.tian@...el.com, yi.l.liu@...el.com, zhiw@...dia.com,
	aniketa@...dia.com, cjia@...dia.com, kwankhede@...dia.com,
	targupta@...dia.com, vsethi@...dia.com, acurrid@...dia.com,
	apopple@...dia.com, jhubbard@...dia.com, danw@...dia.com,
	anuaggarwal@...dia.com, mochs@...dia.com, kjaju@...dia.com,
	dnigam@...dia.com, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [RFC 07/14] vfio/nvgrace-egm: Register auxiliary driver ops

On Thu, Sep 04, 2025 at 04:08:21AM +0000, ankita@...dia.com wrote:
> +static const struct auxiliary_device_id egm_id_table[] = {
> +	{ .name = "nvgrace_gpu_vfio_pci.egm" },
> +	{ .name = "nvidia_vgpu_vfio.egm" },

Not in tree

>  static char *egm_devnode(const struct device *device, umode_t *mode)
>  {
>  	if (mode)
> @@ -35,19 +59,28 @@ static int __init nvgrace_egm_init(void)
>  
>  	class = class_create(NVGRACE_EGM_DEV_NAME);
>  	if (IS_ERR(class)) {
> -		unregister_chrdev_region(dev, MAX_EGM_NODES);
> -		return PTR_ERR(class);
> +		ret = PTR_ERR(class);
> +		goto unregister_chrdev;
>  	}
>  
>  	class->devnode = egm_devnode;
>  
> -	return 0;
> +	ret = auxiliary_driver_register(&egm_driver);
> +	if (!ret)
> +		goto fn_exit;
> +
> +	class_destroy(class);
> +unregister_chrdev:
> +	unregister_chrdev_region(dev, MAX_EGM_NODES);
> +fn_exit:
> +	return ret;
>  }
>  
>  static void __exit nvgrace_egm_cleanup(void)
>  {
>  	class_destroy(class);
>  	unregister_chrdev_region(dev, MAX_EGM_NODES);
> +	auxiliary_driver_unregister(&egm_driver);
>  }

Out of order, the order should be the reverse of init. This will UAF
the class as-is.

Jason