// SPDX-License-Identifier: GPL-2.0-only /* Copyright (c) 2023 Benjamin Tissoires */ #include "vmlinux.h" #include "hid_bpf.h" #include "hid_bpf_helpers.h" #include <bpf/bpf_tracing.h> #define VID_HP 0x03F0 #define PID_ELITE_PRESENTER 0x464A HID_BPF_CONFIG( HID_DEVICE(BUS_BLUETOOTH, HID_GROUP_GENERIC, VID_HP, PID_ELITE_PRESENTER) ); /* * Already fixed as of commit 0db117359e47 ("HID: add quirk for 03f0:464a * HP Elite Presenter Mouse") in the kernel, but this is a slightly better * fix. * * The HP Elite Presenter Mouse HID Record Descriptor shows * two mice (Report ID 0x1 and 0x2), one keypad (Report ID 0x5), * two Consumer Controls (Report IDs 0x6 and 0x3). * Prior to these fixes it registers one mouse, one keypad * and one Consumer Control, and it was usable only as a * digital laser pointer (one of the two mouses). * We replace the second mouse collection with a pointer collection, * allowing to use the device both as a mouse and a digital laser * pointer. */ SEC("fmod_ret/hid_bpf_rdesc_fixup") int BPF_PROG(hid_fix_rdesc, struct hid_bpf_ctx *hctx) { __u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 4096 /* size */); if (!data) return 0; /* EPERM check */ /* replace application mouse by application pointer on the second collection */ if (data[79] == 0x02) data[79] = 0x01; return 0; } SEC("syscall") int probe(struct hid_bpf_probe_args *ctx) { ctx->retval = ctx->rdesc_size != 264; if (ctx->retval) ctx->retval = -EINVAL; return 0; } char _license[] SEC("license") = "GPL";