From patchwork Fri Nov 12 01:26:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yonghong Song X-Patchwork-Id: 12615997 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33BDAC433F5 for ; Fri, 12 Nov 2021 01:26:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19CCF61268 for ; Fri, 12 Nov 2021 01:26:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233659AbhKLB3O (ORCPT ); Thu, 11 Nov 2021 20:29:14 -0500 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:49568 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S234295AbhKLB3O (ORCPT ); Thu, 11 Nov 2021 20:29:14 -0500 Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.1.2/8.16.1.2) with SMTP id 1AC14Jqe008763 for ; Thu, 11 Nov 2021 17:26:23 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : content-type : content-transfer-encoding : mime-version; s=facebook; bh=4BL4kVS0GMv4wa4f81QgBGAL0BXoAYcI+57Rju8G844=; b=N2kHgznCHyJ5sUJwYry99cVHtoo6DhricZ8xu3wKgAiJ1JeIYtssC8fjFUhR7xKG5ndf 535TccVlkZztF9khk22Dh/A7HuVxdnaEyIWLooJBANz0e2ILROFbgNAlPUUtMeOjXkBP O0zlwJaxmmvU5uG+trkfUHfLuXZMQ/VlG0A= Received: from mail.thefacebook.com ([163.114.132.120]) by m0001303.ppops.net with ESMTP id 3c9ca7gsy0-18 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 11 Nov 2021 17:26:23 -0800 Received: from intmgw001.05.ash9.facebook.com (2620:10d:c085:208::11) by mail.thefacebook.com (2620:10d:c085:21d::4) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.14; Thu, 11 Nov 2021 17:26:14 -0800 Received: by devbig309.ftw3.facebook.com (Postfix, from userid 128203) id 8411524C5B11; Thu, 11 Nov 2021 17:26:04 -0800 (PST) From: Yonghong Song To: CC: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , "Jose E . Marchesi" , Subject: [PATCH bpf-next v3 00/10] Support BTF_KIND_TYPE_TAG for btf_type_tag attributes Date: Thu, 11 Nov 2021 17:26:04 -0800 Message-ID: <20211112012604.1504583-1-yhs@fb.com> X-Mailer: git-send-email 2.30.2 X-FB-Internal: Safe X-FB-Source: Intern X-Proofpoint-ORIG-GUID: iTxuKW3SAgcS0evfzXn3ltsC84yUIhya X-Proofpoint-GUID: iTxuKW3SAgcS0evfzXn3ltsC84yUIhya X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.0.607.475 definitions=2021-11-11_09,2021-11-11_01,2020-04-07_01 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 suspectscore=0 priorityscore=1501 spamscore=0 adultscore=0 malwarescore=0 lowpriorityscore=0 impostorscore=0 mlxscore=0 bulkscore=0 clxscore=1015 mlxlogscore=708 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2110150000 definitions=main-2111120005 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net LLVM patches ([1] for clang, [2] and [3] for BPF backend) added support for btf_type_tag attributes. This patch added support for the kernel. The main motivation for btf_type_tag is to bring kernel annotations __user, __rcu etc. to btf. With such information available in btf, bpf verifier can detect mis-usages and reject the program. For example, for __user tagged pointer, developers can then use proper helper like bpf_probe_read_kernel() etc. to read the data. BTF_KIND_TYPE_TAG may also useful for other tracing facility where instead of to require user to specify kernel/user address type, the kernel can detect it by itself with btf. Patch 1 added support in kernel, Patch 2 for libbpf and Patch 3 for bpftool. Patches 4-9 are for bpf selftests and Patch 10 updated docs/bpf/btf.rst file with new btf kind. [1] https://reviews.llvm.org/D111199 [2] https://reviews.llvm.org/D113222 [3] https://reviews.llvm.org/D113496 Changelogs: v2 -> v3: - rebase to resolve merge conflicts. v1 -> v2: - add more dedup tests. - remove build requirement for LLVM=1. - remove testing macro __has_attribute in bpf programs as it is always defined in recent clang compilers. Yonghong Song (10): bpf: Support BTF_KIND_TYPE_TAG for btf_type_tag attributes libbpf: Support BTF_KIND_TYPE_TAG bpftool: Support BTF_KIND_TYPE_TAG selftests/bpf: Test libbpf API function btf__add_type_tag() selftests/bpf: Add BTF_KIND_TYPE_TAG unit tests selftests/bpf: Test BTF_KIND_DECL_TAG for deduplication selftests/bpf: Rename progs/tag.c to progs/btf_decl_tag.c selftests/bpf: Add a C test for btf_type_tag selftests/bpf: Clarify llvm dependency with btf_tag selftest docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support Documentation/bpf/btf.rst | 13 +- include/uapi/linux/btf.h | 3 +- kernel/bpf/btf.c | 14 +- tools/bpf/bpftool/btf.c | 2 + tools/include/uapi/linux/btf.h | 3 +- tools/lib/bpf/btf.c | 23 +++ tools/lib/bpf/btf.h | 9 +- tools/lib/bpf/btf_dump.c | 9 + tools/lib/bpf/libbpf.c | 31 +++- tools/lib/bpf/libbpf.map | 1 + tools/lib/bpf/libbpf_internal.h | 2 + tools/testing/selftests/bpf/README.rst | 9 +- tools/testing/selftests/bpf/btf_helpers.c | 4 +- tools/testing/selftests/bpf/prog_tests/btf.c | 157 +++++++++++++++++- .../selftests/bpf/prog_tests/btf_tag.c | 44 ++++- .../selftests/bpf/prog_tests/btf_write.c | 67 +++++--- .../bpf/progs/{tag.c => btf_decl_tag.c} | 4 - .../selftests/bpf/progs/btf_type_tag.c | 25 +++ tools/testing/selftests/bpf/test_btf.h | 3 + 19 files changed, 370 insertions(+), 53 deletions(-) rename tools/testing/selftests/bpf/progs/{tag.c => btf_decl_tag.c} (94%) create mode 100644 tools/testing/selftests/bpf/progs/btf_type_tag.c