From patchwork Mon Apr 27 20:12:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yonghong Song X-Patchwork-Id: 220472 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D199C81B42 for ; Mon, 27 Apr 2020 20:12:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E47EC2070B for ; Mon, 27 Apr 2020 20:12:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="RE2RnCXT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726791AbgD0UMq (ORCPT ); Mon, 27 Apr 2020 16:12:46 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:26852 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726661AbgD0UMo (ORCPT ); Mon, 27 Apr 2020 16:12:44 -0400 Received: from pps.filterd (m0044010.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 03RKAomR031134 for ; Mon, 27 Apr 2020 13:12:44 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=FlGBMjFQ58EfoYMjgVzYQGqT38VwRmb0fAAp4dHeBEM=; b=RE2RnCXTYm2NqYToXxK0glrj9/9A/Nlkayold1Zn5igT/QhRWAZmvD99Vi8nD9t/Y/Ow +q4mmJJk3DYV0Ma9xsl2Dt3Wqju0teYKfP4jg7lAtUXW2F5IHRI+I/Fv6ejbVdiigbl5 ZzvtZl4kfhrVh/0y1AHTNlPVNLYyRufo4OE= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 30n57q245w-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Mon, 27 Apr 2020 13:12:44 -0700 Received: from intmgw004.08.frc2.facebook.com (2620:10d:c085:208::f) by mail.thefacebook.com (2620:10d:c085:11d::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1847.3; Mon, 27 Apr 2020 13:12:43 -0700 Received: by devbig003.ftw2.facebook.com (Postfix, from userid 128203) id 2BF2F3700871; Mon, 27 Apr 2020 13:12:39 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Yonghong Song Smtp-Origin-Hostname: devbig003.ftw2.facebook.com To: Andrii Nakryiko , , Martin KaFai Lau , CC: Alexei Starovoitov , Daniel Borkmann , Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH bpf-next v1 04/19] bpf: allow loading of a bpf_iter program Date: Mon, 27 Apr 2020 13:12:39 -0700 Message-ID: <20200427201239.2994896-1-yhs@fb.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200427201235.2994549-1-yhs@fb.com> References: <20200427201235.2994549-1-yhs@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.676 definitions=2020-04-27_15:2020-04-27,2020-04-27 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 suspectscore=0 lowpriorityscore=0 mlxscore=0 spamscore=0 phishscore=0 adultscore=0 clxscore=1015 impostorscore=0 malwarescore=0 mlxlogscore=999 priorityscore=1501 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004270164 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org A bpf_iter program is a tracing program with attach type BPF_TRACE_ITER. The load attribute attach_btf_id is used by the verifier against a particular kernel function, e.g., __bpf_iter__bpf_map in our previous bpf_map iterator. The program return value must be 0 for now. In the future, other return values may be used for filtering or teminating the iterator. Signed-off-by: Yonghong Song --- include/uapi/linux/bpf.h | 1 + kernel/bpf/verifier.c | 20 ++++++++++++++++++++ tools/include/uapi/linux/bpf.h | 1 + 3 files changed, 22 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 4a6c47f3febe..f39b9fec37ab 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -215,6 +215,7 @@ enum bpf_attach_type { BPF_TRACE_FEXIT, BPF_MODIFY_RETURN, BPF_LSM_MAC, + BPF_TRACE_ITER, __MAX_BPF_ATTACH_TYPE }; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 91728e0f27eb..fd36c22685d9 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7074,6 +7074,11 @@ static int check_return_code(struct bpf_verifier_env *env) return 0; range = tnum_const(0); break; + case BPF_PROG_TYPE_TRACING: + if (env->prog->expected_attach_type != BPF_TRACE_ITER) + return 0; + range = tnum_const(0); + break; default: return 0; } @@ -10454,6 +10459,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env) struct bpf_prog *tgt_prog = prog->aux->linked_prog; u32 btf_id = prog->aux->attach_btf_id; const char prefix[] = "btf_trace_"; + struct btf_func_model fmodel; int ret = 0, subprog = -1, i; struct bpf_trampoline *tr; const struct btf_type *t; @@ -10595,6 +10601,20 @@ static int check_attach_btf_id(struct bpf_verifier_env *env) prog->aux->attach_func_proto = t; prog->aux->attach_btf_trace = true; return 0; + case BPF_TRACE_ITER: + if (!btf_type_is_func(t)) { + verbose(env, "attach_btf_id %u is not a function\n", + btf_id); + return -EINVAL; + } + t = btf_type_by_id(btf, t->type); + if (!btf_type_is_func_proto(t)) + return -EINVAL; + prog->aux->attach_func_name = tname; + prog->aux->attach_func_proto = t; + ret = btf_distill_func_proto(&env->log, btf, t, + tname, &fmodel); + return ret; default: if (!prog_extension) return -EINVAL; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 4a6c47f3febe..f39b9fec37ab 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -215,6 +215,7 @@ enum bpf_attach_type { BPF_TRACE_FEXIT, BPF_MODIFY_RETURN, BPF_LSM_MAC, + BPF_TRACE_ITER, __MAX_BPF_ATTACH_TYPE };