From patchwork Sat Aug 1 17:03:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 1339813 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BJr8y1rysz9s1x for ; Sun, 2 Aug 2020 03:04:18 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728047AbgHARER convert rfc822-to-8bit (ORCPT ); Sat, 1 Aug 2020 13:04:17 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:24195 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728027AbgHAREQ (ORCPT ); Sat, 1 Aug 2020 13:04:16 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-272-c_HjdDqXNzmtqItlZqcycA-1; Sat, 01 Aug 2020 13:04:11 -0400 X-MC-Unique: c_HjdDqXNzmtqItlZqcycA-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 2B4868015F3; Sat, 1 Aug 2020 17:04:09 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.39]) by smtp.corp.redhat.com (Postfix) with ESMTP id 082EB1C4; Sat, 1 Aug 2020 17:04:05 +0000 (UTC) From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Song Liu , Yonghong Song , Martin KaFai Lau , David Miller , John Fastabend , Wenbo Zhang , KP Singh , Brendan Gregg , Florent Revest , Al Viro Subject: [PATCH v9 bpf-next 12/14] selftests/bpf: Add verifier test for d_path helper Date: Sat, 1 Aug 2020 19:03:20 +0200 Message-Id: <20200801170322.75218-13-jolsa@kernel.org> In-Reply-To: <20200801170322.75218-1-jolsa@kernel.org> References: <20200801170322.75218-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Adding verifier test for attaching tracing program and calling d_path helper from within and testing that it's allowed for dentry_open function and denied for 'd_path' function with appropriate error. Acked-by: Andrii Nakryiko Signed-off-by: Jiri Olsa --- tools/testing/selftests/bpf/test_verifier.c | 19 +++++++++- tools/testing/selftests/bpf/verifier/d_path.c | 37 +++++++++++++++++++ 2 files changed, 55 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/verifier/d_path.c diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index 78a6bae56ea6..9be395d9dc64 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -114,6 +114,7 @@ struct bpf_test { bpf_testdata_struct_t retvals[MAX_TEST_RUNS]; }; enum bpf_attach_type expected_attach_type; + const char *kfunc; }; /* Note we want this to be 64 bit aligned so that the end of our array is @@ -984,8 +985,24 @@ static void do_test_single(struct bpf_test *test, bool unpriv, attr.log_level = 4; attr.prog_flags = pflags; + if (prog_type == BPF_PROG_TYPE_TRACING && test->kfunc) { + attr.attach_btf_id = libbpf_find_vmlinux_btf_id(test->kfunc, + attr.expected_attach_type); + if (attr.attach_btf_id < 0) { + printf("FAIL\nFailed to find BTF ID for '%s'!\n", + test->kfunc); + (*errors)++; + return; + } + } + fd_prog = bpf_load_program_xattr(&attr, bpf_vlog, sizeof(bpf_vlog)); - if (fd_prog < 0 && !bpf_probe_prog_type(prog_type, 0)) { + + /* BPF_PROG_TYPE_TRACING requires more setup and + * bpf_probe_prog_type won't give correct answer + */ + if (fd_prog < 0 && prog_type != BPF_PROG_TYPE_TRACING && + !bpf_probe_prog_type(prog_type, 0)) { printf("SKIP (unsupported program type %d)\n", prog_type); skips++; goto close_fds; diff --git a/tools/testing/selftests/bpf/verifier/d_path.c b/tools/testing/selftests/bpf/verifier/d_path.c new file mode 100644 index 000000000000..b988396379a7 --- /dev/null +++ b/tools/testing/selftests/bpf/verifier/d_path.c @@ -0,0 +1,37 @@ +{ + "d_path accept", + .insns = { + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, 0), + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), + BPF_MOV64_IMM(BPF_REG_6, 0), + BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_6, 0), + BPF_LD_IMM64(BPF_REG_3, 8), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_d_path), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .result = ACCEPT, + .prog_type = BPF_PROG_TYPE_TRACING, + .expected_attach_type = BPF_TRACE_FENTRY, + .kfunc = "dentry_open", +}, +{ + "d_path reject", + .insns = { + BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_1, 0), + BPF_MOV64_REG(BPF_REG_2, BPF_REG_10), + BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8), + BPF_MOV64_IMM(BPF_REG_6, 0), + BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_6, 0), + BPF_LD_IMM64(BPF_REG_3, 8), + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_d_path), + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }, + .errstr = "helper call is not allowed in probe", + .result = REJECT, + .prog_type = BPF_PROG_TYPE_TRACING, + .expected_attach_type = BPF_TRACE_FENTRY, + .kfunc = "d_path", +},