From patchwork Fri Mar 4 17:28:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 548647 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32200C433EF for ; Fri, 4 Mar 2022 17:29:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238806AbiCDRaF (ORCPT ); Fri, 4 Mar 2022 12:30:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238586AbiCDRaE (ORCPT ); Fri, 4 Mar 2022 12:30:04 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 4317A144F41 for ; Fri, 4 Mar 2022 09:29:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646414955; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=JLcaNFoE2+O0p0Og9VR8JqYYYchyQ3ie9yDd/O1/oyc=; b=Uftmb+VjS2N6+nd06Mc+vE1JOImM/86003dFyQEcGJRkLSQ13UvUxScsXboK2GFiDcO1BS JlVWkC5+4FGPPc37ekz7yYoNh2HS3+bia2zWWn+ESwka5dlSGHOLml66u9XcXuK0iepmDX PUgKONVBrtFsa45h2W/lgg+E/XlAUrU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-92-k_uNrN6uNGuz396T5P2sYg-1; Fri, 04 Mar 2022 12:29:12 -0500 X-MC-Unique: k_uNrN6uNGuz396T5P2sYg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 9CF521006AA5; Fri, 4 Mar 2022 17:29:09 +0000 (UTC) Received: from plouf.redhat.com (unknown [10.39.192.55]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2E74386599; Fri, 4 Mar 2022 17:28:58 +0000 (UTC) From: Benjamin Tissoires To: Greg KH , Jiri Kosina , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Shuah Khan , Dave Marchevsky , Joe Stringer Cc: Tero Kristo , linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, Benjamin Tissoires Subject: [PATCH bpf-next v2 00/28] Introduce eBPF support for HID devices Date: Fri, 4 Mar 2022 18:28:24 +0100 Message-Id: <20220304172852.274126-1-benjamin.tissoires@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org Hi, This is a followup of my v1 at [0]. The short summary of the previous cover letter and discussions is that HID could benefit from BPF for the following use cases: - simple fixup of report descriptor: benefits are faster development time and testing, with the produced bpf program being shipped in the kernel directly (the shipping part is *not* addressed here). - Universal Stylus Interface: allows a user-space program to define its own kernel interface - Surface Dial: somehow similar to the previous one except that userspace can decide to change the shape of the exported device - firewall: still partly missing there, there is not yet interception of hidraw calls, but it's coming in a followup series, I promise - tracing: well, tracing. I tried to address as many comments as I could and here is the short log of changes: v2: === - split the series by subsystem (bpf, HID, libbpf, selftests and samples) - Added an extra patch at the beginning to not require CAP_NET_ADMIN for BPF_PROG_TYPE_LIRC_MODE2 (please shout if this is wrong) - made the bpf context attached to HID program of dynamic size: * the first 1 kB will be able to be addressed directly * the rest can be retrieved through bpf_hid_{set|get}_data (note that I am definitivey not happy with that API, because there is part of it in bits and other in bytes. ouch) - added an extra patch to prevent non GPL HID bpf programs to be loaded of type BPF_PROG_TYPE_HID * same here, not really happy but I don't know where to put that check in verifier.c - added a new flag BPF_F_INSERT_HEAD for BPF_LINK_CREATE syscall when in used with HID program types. * this flag is used for tracing, to be able to load a program before any others that might already have been inserted and that might change the data stream. Cheers, Benjamin [0] https://lore.kernel.org/linux-input/20220224110828.2168231-1-benjamin.tissoires@redhat.com/T/#t Benjamin Tissoires (28): bpf: add new is_sys_admin_prog_type() helper bpf: introduce hid program type HID: hook up with bpf libbpf: add HID program type and API selftests/bpf: add tests for the HID-bpf initial implementation samples/bpf: add new hid_mouse example bpf/hid: add a new attach type to change the report descriptor HID: allow to change the report descriptor from an eBPF program libbpf: add new attach type BPF_HID_RDESC_FIXUP selftests/bpf: add report descriptor fixup tests samples/bpf: add a report descriptor fixup bpf/hid: add hid_{get|set}_data helpers HID: bpf: implement hid_bpf_get|set_data selftests/bpf: add tests for hid_{get|set}_data helpers bpf/hid: add new BPF type to trigger commands from userspace libbpf: add new attach type BPF_HID_USER_EVENT selftests/bpf: add test for user call of HID bpf programs selftests/bpf: hid: rely on uhid event to know if a test device is ready bpf/hid: add bpf_hid_raw_request helper function HID: add implementation of bpf_hid_raw_request selftests/bpf: add tests for bpf_hid_hw_request bpf/verifier: prevent non GPL programs to be loaded against HID HID: bpf: compute only the required buffer size for the device HID: bpf: only call hid_bpf_raw_event() if a ctx is available bpf/hid: Add a flag to add the program at the beginning of the list libbpf: add handling for BPF_F_INSERT_HEAD in HID programs selftests/bpf: Add a test for BPF_F_INSERT_HEAD samples/bpf: fix bpf_program__attach_hid() api change drivers/hid/Makefile | 1 + drivers/hid/hid-bpf.c | 361 +++++++++ drivers/hid/hid-core.c | 34 +- include/linux/bpf-hid.h | 129 +++ include/linux/bpf_types.h | 4 + include/linux/hid.h | 25 + include/uapi/linux/bpf.h | 59 ++ include/uapi/linux/bpf_hid.h | 50 ++ kernel/bpf/Makefile | 3 + kernel/bpf/hid.c | 652 +++++++++++++++ kernel/bpf/syscall.c | 26 +- kernel/bpf/verifier.c | 7 + samples/bpf/.gitignore | 1 + samples/bpf/Makefile | 4 + samples/bpf/hid_mouse_kern.c | 91 +++ samples/bpf/hid_mouse_user.c | 129 +++ tools/include/uapi/linux/bpf.h | 59 ++ tools/lib/bpf/libbpf.c | 22 +- tools/lib/bpf/libbpf.h | 2 + tools/lib/bpf/libbpf.map | 1 + tools/testing/selftests/bpf/prog_tests/hid.c | 788 +++++++++++++++++++ tools/testing/selftests/bpf/progs/hid.c | 216 +++++ 22 files changed, 2649 insertions(+), 15 deletions(-) create mode 100644 drivers/hid/hid-bpf.c create mode 100644 include/linux/bpf-hid.h create mode 100644 include/uapi/linux/bpf_hid.h create mode 100644 kernel/bpf/hid.c create mode 100644 samples/bpf/hid_mouse_kern.c create mode 100644 samples/bpf/hid_mouse_user.c create mode 100644 tools/testing/selftests/bpf/prog_tests/hid.c create mode 100644 tools/testing/selftests/bpf/progs/hid.c Reviewed-by: Tero Kristo Tested-by: Tero Kristo