From patchwork Tue Jul 12 14:58:46 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 590592 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 C543AC43334 for ; Tue, 12 Jul 2022 15:06:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234073AbiGLPGw (ORCPT ); Tue, 12 Jul 2022 11:06:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34008 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233778AbiGLPGP (ORCPT ); Tue, 12 Jul 2022 11:06:15 -0400 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 A95A2C4463 for ; Tue, 12 Jul 2022 08:00:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1657638033; 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: in-reply-to:in-reply-to:references:references; bh=FgPb1yfv9B32xgkaX5+oDU5OXhR5x9/eHCMAL1/HRjY=; b=Mhe06ZsTOIVALTFKLGhvq6AMI+iKJtUVVyGIBEG9/tCfuyjmz2h0tr0a+4c1MR3AJYQVj9 BmTyqXCQo6Fp1gUBIFzgEvbrcZUS95+Wrc1gXUoGd+9cE/6jKKPjjo7frdVxjtsHZILy+q PMhUnk1nAH+/OW9ccGuc+nb9lDIaZkw= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-350-mtZEntoHN_quYBfv2RqONA-1; Tue, 12 Jul 2022 11:00:24 -0400 X-MC-Unique: mtZEntoHN_quYBfv2RqONA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 76362803918; Tue, 12 Jul 2022 15:00:21 +0000 (UTC) Received: from plouf.redhat.com (unknown [10.39.195.8]) by smtp.corp.redhat.com (Postfix) with ESMTP id E6F732166B26; Tue, 12 Jul 2022 15:00:16 +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 , Jonathan Corbet 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, linux-doc@vger.kernel.org, Benjamin Tissoires Subject: [PATCH bpf-next v6 19/23] selftests/bpf: add report descriptor fixup tests Date: Tue, 12 Jul 2022 16:58:46 +0200 Message-Id: <20220712145850.599666-20-benjamin.tissoires@redhat.com> In-Reply-To: <20220712145850.599666-1-benjamin.tissoires@redhat.com> References: <20220712145850.599666-1-benjamin.tissoires@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org Simple report descriptor override in HID: replace part of the report descriptor from a static definition in the bpf kernel program. Note that this test should be run last because we disconnect/reconnect the device, meaning that it changes the overall uhid device. Signed-off-by: Benjamin Tissoires --- no changes in v6 changes in v5: - amended for the new API not in v4 changes in v3: - added a comment to mention that this test needs to be run last changes in v2: - split the series by bpf/libbpf/hid/selftests and samples --- tools/testing/selftests/bpf/prog_tests/hid.c | 76 ++++++++++++++++++++ tools/testing/selftests/bpf/progs/hid.c | 53 ++++++++++++++ 2 files changed, 129 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/hid.c b/tools/testing/selftests/bpf/prog_tests/hid.c index 19172d3e0f44..9dc5f0038472 100644 --- a/tools/testing/selftests/bpf/prog_tests/hid.c +++ b/tools/testing/selftests/bpf/prog_tests/hid.c @@ -9,6 +9,7 @@ #include #include #include +#include #include static unsigned char rdesc[] = { @@ -769,6 +770,73 @@ static int test_hid_user_raw_request_call(int uhid_fd, int dev_id) return ret; } +/* + * Attach hid_rdesc_fixup to the given uhid device, + * retrieve and open the matching hidraw node, + * check that the hidraw report descriptor has been updated. + */ +static int test_rdesc_fixup(void) +{ + struct hidraw_report_descriptor rpt_desc = {0}; + struct test_params params; + int err, uhid_fd, desc_size, hidraw_fd = -1, ret = -1; + int dev_id; + void *uhid_err; + pthread_t tid; + bool started = false; + + dev_id = rand() % 1024; + + uhid_fd = setup_uhid(dev_id); + if (!ASSERT_GE(uhid_fd, 0, "setup uhid")) + return uhid_fd; + + err = prep_test(dev_id, "hid_rdesc_fixup", ¶ms); + if (!ASSERT_EQ(err, 0, "prep_test(hid_rdesc_fixup)")) + goto cleanup; + + err = uhid_start_listener(&tid, uhid_fd); + ASSERT_OK(err, "uhid_start_listener"); + + started = true; + + hidraw_fd = params.hidraw_fd; + + /* check that hid_rdesc_fixup() was executed */ + ASSERT_EQ(params.skel->data->callback2_check, 0x21, "callback_check2"); + + /* read the exposed report descriptor from hidraw */ + err = ioctl(hidraw_fd, HIDIOCGRDESCSIZE, &desc_size); + if (!ASSERT_GE(err, 0, "HIDIOCGRDESCSIZE")) + goto cleanup; + + /* ensure the new size of the rdesc is bigger than the old one */ + if (!ASSERT_GT(desc_size, sizeof(rdesc), "new_rdesc_size")) + goto cleanup; + + rpt_desc.size = desc_size; + err = ioctl(hidraw_fd, HIDIOCGRDESC, &rpt_desc); + if (!ASSERT_GE(err, 0, "HIDIOCGRDESC")) + goto cleanup; + + if (!ASSERT_EQ(rpt_desc.value[4], 0x42, "hid_rdesc_fixup")) + goto cleanup; + + ret = 0; + +cleanup: + cleanup_test(¶ms); + + if (started) { + destroy(uhid_fd); + pthread_join(tid, &uhid_err); + err = (int)(long)uhid_err; + CHECK_FAIL(err); + } + + return ret; +} + void serial_test_hid_bpf(void) { int err, uhid_fd; @@ -799,6 +867,14 @@ void serial_test_hid_bpf(void) err = test_hid_user_raw_request_call(uhid_fd, dev_id); ASSERT_OK(err, "hid_user_raw_request"); + /* + * this test should be run last because we disconnect/reconnect + * the device, meaning that it changes the overall uhid device + * and messes up with the thread that reads uhid events. + */ + err = test_rdesc_fixup(); + ASSERT_OK(err, "hid_rdesc_fixup"); + destroy(uhid_fd); pthread_join(tid, &uhid_err); diff --git a/tools/testing/selftests/bpf/progs/hid.c b/tools/testing/selftests/bpf/progs/hid.c index 0be319c11575..863c37ddf5ff 100644 --- a/tools/testing/selftests/bpf/progs/hid.c +++ b/tools/testing/selftests/bpf/progs/hid.c @@ -99,3 +99,56 @@ int hid_user_raw_request(struct hid_hw_request_syscall_args *args) return 0; } + +static const __u8 rdesc[] = { + 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */ + 0x09, 0x32, /* USAGE (Z) */ + 0x95, 0x01, /* REPORT_COUNT (1) */ + 0x81, 0x06, /* INPUT (Data,Var,Rel) */ + + 0x06, 0x00, 0xff, /* Usage Page (Vendor Defined Page 1) */ + 0x19, 0x01, /* USAGE_MINIMUM (1) */ + 0x29, 0x03, /* USAGE_MAXIMUM (3) */ + 0x15, 0x00, /* LOGICAL_MINIMUM (0) */ + 0x25, 0x01, /* LOGICAL_MAXIMUM (1) */ + 0x95, 0x03, /* REPORT_COUNT (3) */ + 0x75, 0x01, /* REPORT_SIZE (1) */ + 0x91, 0x02, /* Output (Data,Var,Abs) */ + 0x95, 0x01, /* REPORT_COUNT (1) */ + 0x75, 0x05, /* REPORT_SIZE (5) */ + 0x91, 0x01, /* Output (Cnst,Var,Abs) */ + + 0x06, 0x00, 0xff, /* Usage Page (Vendor Defined Page 1) */ + 0x19, 0x06, /* USAGE_MINIMUM (6) */ + 0x29, 0x08, /* USAGE_MAXIMUM (8) */ + 0x15, 0x00, /* LOGICAL_MINIMUM (0) */ + 0x25, 0x01, /* LOGICAL_MAXIMUM (1) */ + 0x95, 0x03, /* REPORT_COUNT (3) */ + 0x75, 0x01, /* REPORT_SIZE (1) */ + 0xb1, 0x02, /* Feature (Data,Var,Abs) */ + 0x95, 0x01, /* REPORT_COUNT (1) */ + 0x75, 0x05, /* REPORT_SIZE (5) */ + 0x91, 0x01, /* Output (Cnst,Var,Abs) */ + + 0xc0, /* END_COLLECTION */ + 0xc0, /* END_COLLECTION */ +}; + +SEC("?fmod_ret/hid_bpf_rdesc_fixup") +int BPF_PROG(hid_rdesc_fixup, struct hid_bpf_ctx *hid_ctx) +{ + __u8 *data = hid_bpf_get_data(hid_ctx, 0 /* offset */, 4096 /* size */); + + if (!data) + return 0; /* EPERM check */ + + callback2_check = data[4]; + + /* insert rdesc at offset 73 */ + __builtin_memcpy(&data[73], rdesc, sizeof(rdesc)); + + /* Change Usage Vendor globally */ + data[4] = 0x42; + + return sizeof(rdesc) + 73; +}