On Thu, Feb 24, 2022 at 12:41 PM Greg KH [off-list ref] wrote:

On Thu, Feb 24, 2022 at 12:08:23PM +0100, Benjamin Tissoires wrote:

quoted

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. Even __u16 should be enough, given that the upper bound is
16384. I'll amend it in v2.

Cheers,
Benjamin

thanks,

greg k-h