From patchwork Wed Jun 26 13:46:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 13712975 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 786F818E755; Wed, 26 Jun 2024 13:47:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719409635; cv=none; b=YEGf4G0SDa+C1d2gy5fYZd8yIcziu92VBT6xALJkG/6NiOcjGbxUKRAeG9PQPhdOGnGv4tAYCgnxd5yBAcJkddX/h+ascP3nZnbbAayH4BgpgiQRfsfOCw/1pkTDM5nkW9aK0RDzvpW3xjLfRqFmFrANbi3d0EEg/eLx01L5gOM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719409635; c=relaxed/simple; bh=coSvairEXZ/UoBj93IfzT1BpGcOK/jnPrORkflCNJ84=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=NPqwuL+s//UYPAZ8sBkQ2mDNJw94M/bHi+uageZJGGa+WtL3j5nq6J6H2kvaSdILv75kIcC/7+TD7WUQIYYLe/xi+2BZZJKcs7SzIb+6C55UyeV7uaIt418zdA+5NA6Y9HrzwgG0G1B71NNzWSyi3bps2U7mfDkAdJpF4eGvExI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M7TgyvOq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="M7TgyvOq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F55BC4AF07; Wed, 26 Jun 2024 13:47:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719409635; bh=coSvairEXZ/UoBj93IfzT1BpGcOK/jnPrORkflCNJ84=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=M7TgyvOqh+G8JBHZHxNOGoIIsb0OsioBMMg+gOn3TNV2PLOLkJ4AFX/7QXQhW2132 XYagHiEHIDF3QcAPTMADf7q5VPdhGTK7+owjeNWkzBJ1cXERnJ/1h1iykUccDUp4PE kuD1m9RrzITqb69QiZOIi/HxAY299c+0rPcgtu0J3NNyRRKFeEt6ndbKgLrReKiIKC wguo+WVHSMkOPKQiq7dWMNaB4ardr+pcIv2Rpi4IsAoT+ONvZ+YBv5mbuX82d2JhHw KXt2QnVFzV2gGVnLVKrRtAA2ERheboepDnc0EgKd8WTobmRObueqSzVRoAdBmWSofZ hIdu+Z7T9P6Fg== From: Benjamin Tissoires Date: Wed, 26 Jun 2024 15:46:34 +0200 Subject: [PATCH HID v2 13/13] selftests/hid: add an infinite loop test for hid_bpf_try_input_report Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240626-hid_hw_req_bpf-v2-13-cfd60fb6c79f@kernel.org> References: <20240626-hid_hw_req_bpf-v2-0-cfd60fb6c79f@kernel.org> In-Reply-To: <20240626-hid_hw_req_bpf-v2-0-cfd60fb6c79f@kernel.org> To: Jiri Kosina , Alexei Starovoitov , Shuah Khan , Jonathan Corbet Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org, Benjamin Tissoires X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1719409602; l=3521; i=bentiss@kernel.org; s=20230215; h=from:subject:message-id; bh=coSvairEXZ/UoBj93IfzT1BpGcOK/jnPrORkflCNJ84=; b=y3R38nLnIx95jobpAICJH1TPSo58IZ3qiL3BnUPgxNlYvk6mTJ8bIWv2euPxrMe7T3qg3vOGa jOkMsJiAcShAU0XVpvS0VDk6ymvazKa9awoDZgpz/V6UVXz4BJjAvYA X-Developer-Key: i=bentiss@kernel.org; a=ed25519; pk=7D1DyAVh6ajCkuUTudt/chMuXWIJHlv2qCsRkIizvFw= We don't want this call to allow an infinite loop in HID-BPF, so let's have some tests. Signed-off-by: Benjamin Tissoires --- no changes in v2 --- tools/testing/selftests/hid/hid_bpf.c | 41 +++++++++++++++++++++++++++++++++ tools/testing/selftests/hid/progs/hid.c | 37 +++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+) diff --git a/tools/testing/selftests/hid/hid_bpf.c b/tools/testing/selftests/hid/hid_bpf.c index 36bbad8e0f9f..dc0408a831d0 100644 --- a/tools/testing/selftests/hid/hid_bpf.c +++ b/tools/testing/selftests/hid/hid_bpf.c @@ -1204,6 +1204,47 @@ TEST_F(hid_bpf, test_multiply_events) ASSERT_EQ(buf[1], 52); } +/* + * Call hid_bpf_input_report against the given uhid device, + * check that the program is not making infinite loops. + */ +TEST_F(hid_bpf, test_hid_infinite_loop_input_report_call) +{ + const struct test_program progs[] = { + { .name = "hid_test_infinite_loop_input_report" }, + }; + __u8 buf[10] = {0}; + int err; + + LOAD_PROGRAMS(progs); + + /* emit hid_hw_output_report from hidraw */ + buf[0] = 1; /* report ID */ + buf[1] = 2; + buf[2] = 42; + + uhid_send_event(_metadata, self->uhid_fd, buf, 6); + + /* read the data from hidraw */ + memset(buf, 0, sizeof(buf)); + err = read(self->hidraw_fd, buf, sizeof(buf)); + ASSERT_EQ(err, 6) TH_LOG("read_hidraw"); + ASSERT_EQ(buf[0], 1); + ASSERT_EQ(buf[1], 3); + + /* read the data from hidraw: hid_bpf_try_input_report should work exactly one time */ + memset(buf, 0, sizeof(buf)); + err = read(self->hidraw_fd, buf, sizeof(buf)); + ASSERT_EQ(err, 6) TH_LOG("read_hidraw"); + ASSERT_EQ(buf[0], 1); + ASSERT_EQ(buf[1], 4); + + /* read the data from hidraw: there should be none */ + memset(buf, 0, sizeof(buf)); + err = read(self->hidraw_fd, buf, sizeof(buf)); + ASSERT_EQ(err, -1) TH_LOG("read_hidraw"); +} + /* * Attach hid_insert{0,1,2} to the given uhid device, * retrieve and open the matching hidraw node, diff --git a/tools/testing/selftests/hid/progs/hid.c b/tools/testing/selftests/hid/progs/hid.c index 46feeb91d1d5..ee9bbbcf751b 100644 --- a/tools/testing/selftests/hid/progs/hid.c +++ b/tools/testing/selftests/hid/progs/hid.c @@ -561,3 +561,40 @@ SEC(".struct_ops.link") struct hid_bpf_ops test_multiply_events = { .hid_device_event = (void *)hid_test_multiply_events, }; + +SEC("?struct_ops/hid_device_event") +int BPF_PROG(hid_test_infinite_loop_input_report, struct hid_bpf_ctx *hctx, + enum hid_report_type report_type, __u64 source) +{ + __u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 6 /* size */); + __u8 buf[6]; + + if (!data) + return 0; /* EPERM check */ + + /* + * we have to use an intermediate buffer as hid_bpf_input_report + * will memset data to \0 + */ + __builtin_memcpy(buf, data, sizeof(buf)); + + /* always forward the request as-is to the device, hid-bpf should prevent + * infinite loops. + * the return value is ignored so the event is passing to userspace. + */ + + hid_bpf_try_input_report(hctx, report_type, buf, sizeof(buf)); + + /* each time we process the event, we increment by one data[1]: + * after each successful call to hid_bpf_try_input_report, buf + * has been memcopied into data by the kernel. + */ + data[1] += 1; + + return 0; +} + +SEC(".struct_ops.link") +struct hid_bpf_ops test_infinite_loop_input_report = { + .hid_device_event = (void *)hid_test_infinite_loop_input_report, +};