Re: [PATCH bpf-next v1 1/6] HID: initial BPF implementation

[Greg KH]

On Thu, Feb 24, 2022 at 12:08:23PM +0100, Benjamin Tissoires wrote:
> index 000000000000..243ac45a253f
> --- /dev/null
> +++ b/include/uapi/linux/bpf_hid.h
> @@ -0,0 +1,39 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later WITH Linux-syscall-note */
> +
> +/*
> + *  HID BPF public headers
> + *
> + *  Copyright (c) 2021 Benjamin Tissoires
> + */
> +
> +#ifndef _UAPI__LINUX_BPF_HID_H__
> +#define _UAPI__LINUX_BPF_HID_H__
> +
> +#include <linux/types.h>
> +
> +#define HID_BPF_MAX_BUFFER_SIZE		16384		/* 16kb */
> +
> +struct hid_device;
> +
> +enum hid_bpf_event {
> +	HID_BPF_UNDEF = 0,
> +	HID_BPF_DEVICE_EVENT,
> +};
> +
> +/* type is HID_BPF_DEVICE_EVENT */
> +struct hid_bpf_ctx_device_event {
> +	__u8 data[HID_BPF_MAX_BUFFER_SIZE];
> +	unsigned long size;

That's not a valid type to cross the user/kernel boundry, shouldn't it
be "__u64"?  But really, isn't __u32 enough here?

thanks,

greg k-h