From patchwork Wed Aug 24 13:40:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 12953574 X-Patchwork-Delegate: bpf@iogearbox.net 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 6777FC00140 for ; Wed, 24 Aug 2022 13:41:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238427AbiHXNln (ORCPT ); Wed, 24 Aug 2022 09:41:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230513AbiHXNli (ORCPT ); Wed, 24 Aug 2022 09:41:38 -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 ESMTPS id 7A3237E81E for ; Wed, 24 Aug 2022 06:41:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661348480; 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=htqj54Y2CK4iVqQhnJAjtsnF+mPJWGtr+5lqlYqt6Is=; b=LfGf7WbwR7WTSyAGK58g+L20n34fKA/7dHJwQmteHIFtQALMzgB7Q9HkldPItpnBG4K8zh i9JdmKYX5pp1zeQ2YNkBsppoRbYwda6uq2r8fLawWcJyPwfDB0oX7jAVcEJ2lCpBZdDKyq RSWfp6CBLhRcYiD9UFWydviTDv8b8X0= 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-382-pNhDQr55OS6D9HkBU3pBqQ-1; Wed, 24 Aug 2022 09:41:13 -0400 X-MC-Unique: pNhDQr55OS6D9HkBU3pBqQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B3EE885A58A; Wed, 24 Aug 2022 13:41:12 +0000 (UTC) Received: from plouf.redhat.com (unknown [10.39.192.211]) by smtp.corp.redhat.com (Postfix) with ESMTP id 85FC818ECC; Wed, 24 Aug 2022 13:41:09 +0000 (UTC) From: Benjamin Tissoires To: Greg KH , Jiri Kosina , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , Kumar Kartikeya Dwivedi , 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 v9 03/23] selftests/bpf: add test for accessing ctx from syscall program type Date: Wed, 24 Aug 2022 15:40:33 +0200 Message-Id: <20220824134055.1328882-4-benjamin.tissoires@redhat.com> In-Reply-To: <20220824134055.1328882-1-benjamin.tissoires@redhat.com> References: <20220824134055.1328882-1-benjamin.tissoires@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net We need to also export the kfunc set to the syscall program type, and then add a couple of eBPF programs that are testing those calls. The first one checks for valid access, and the second one is OK from a static analysis point of view but fails at run time because we are trying to access outside of the allocated memory. Signed-off-by: Benjamin Tissoires --- no changes in v9 no changes in v8 changes in v7: - add 1 more case to ensure we can read the entire sizeof(ctx) - add a test case for when the context is NULL new in v6 --- net/bpf/test_run.c | 1 + .../selftests/bpf/prog_tests/kfunc_call.c | 28 +++++++++++++++ .../selftests/bpf/progs/kfunc_call_test.c | 36 +++++++++++++++++++ 3 files changed, 65 insertions(+) diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 25d8ecf105aa..f16baf977a21 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -1634,6 +1634,7 @@ static int __init bpf_prog_test_run_init(void) ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_prog_test_kfunc_set); ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &bpf_prog_test_kfunc_set); + ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SYSCALL, &bpf_prog_test_kfunc_set); return ret ?: register_btf_id_dtor_kfuncs(bpf_prog_test_dtor_kfunc, ARRAY_SIZE(bpf_prog_test_dtor_kfunc), THIS_MODULE); diff --git a/tools/testing/selftests/bpf/prog_tests/kfunc_call.c b/tools/testing/selftests/bpf/prog_tests/kfunc_call.c index eede7c304f86..1edad012fe01 100644 --- a/tools/testing/selftests/bpf/prog_tests/kfunc_call.c +++ b/tools/testing/selftests/bpf/prog_tests/kfunc_call.c @@ -9,10 +9,22 @@ #include "cap_helpers.h" +struct syscall_test_args { + __u8 data[16]; + size_t size; +}; + static void test_main(void) { struct kfunc_call_test_lskel *skel; int prog_fd, err; + struct syscall_test_args args = { + .size = 10, + }; + DECLARE_LIBBPF_OPTS(bpf_test_run_opts, syscall_topts, + .ctx_in = &args, + .ctx_size_in = sizeof(args), + ); LIBBPF_OPTS(bpf_test_run_opts, topts, .data_in = &pkt_v4, .data_size_in = sizeof(pkt_v4), @@ -38,6 +50,22 @@ static void test_main(void) ASSERT_OK(err, "bpf_prog_test_run(test_ref_btf_id)"); ASSERT_EQ(topts.retval, 0, "test_ref_btf_id-retval"); + prog_fd = skel->progs.kfunc_syscall_test.prog_fd; + err = bpf_prog_test_run_opts(prog_fd, &syscall_topts); + ASSERT_OK(err, "bpf_prog_test_run(syscall_test)"); + + prog_fd = skel->progs.kfunc_syscall_test_fail.prog_fd; + err = bpf_prog_test_run_opts(prog_fd, &syscall_topts); + ASSERT_ERR(err, "bpf_prog_test_run(syscall_test_fail)"); + + syscall_topts.ctx_in = NULL; + syscall_topts.ctx_size_in = 0; + + prog_fd = skel->progs.kfunc_syscall_test_null.prog_fd; + err = bpf_prog_test_run_opts(prog_fd, &syscall_topts); + ASSERT_OK(err, "bpf_prog_test_run(syscall_test_null)"); + ASSERT_EQ(syscall_topts.retval, 0, "syscall_test_null-retval"); + kfunc_call_test_lskel__destroy(skel); } diff --git a/tools/testing/selftests/bpf/progs/kfunc_call_test.c b/tools/testing/selftests/bpf/progs/kfunc_call_test.c index 5aecbb9fdc68..da7ae0ef9100 100644 --- a/tools/testing/selftests/bpf/progs/kfunc_call_test.c +++ b/tools/testing/selftests/bpf/progs/kfunc_call_test.c @@ -92,4 +92,40 @@ int kfunc_call_test_pass(struct __sk_buff *skb) return 0; } +struct syscall_test_args { + __u8 data[16]; + size_t size; +}; + +SEC("syscall") +int kfunc_syscall_test(struct syscall_test_args *args) +{ + const int size = args->size; + + if (size > sizeof(args->data)) + return -7; /* -E2BIG */ + + bpf_kfunc_call_test_mem_len_pass1(&args->data, sizeof(args->data)); + bpf_kfunc_call_test_mem_len_pass1(&args->data, sizeof(*args)); + bpf_kfunc_call_test_mem_len_pass1(&args->data, size); + + return 0; +} + +SEC("syscall") +int kfunc_syscall_test_null(struct syscall_test_args *args) +{ + bpf_kfunc_call_test_mem_len_pass1(args, 0); + + return 0; +} + +SEC("syscall") +int kfunc_syscall_test_fail(struct syscall_test_args *args) +{ + bpf_kfunc_call_test_mem_len_pass1(&args->data, sizeof(*args) + 1); + + return 0; +} + char _license[] SEC("license") = "GPL";