From mboxrd@z Thu Jan 1 00:00:00 1970 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=-3.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, 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 161BAC43219 for ; Fri, 26 Apr 2019 18:50:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CBADA20B7C for ; Fri, 26 Apr 2019 18:50:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="mBV+Cbhn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726474AbfDZSuU (ORCPT ); Fri, 26 Apr 2019 14:50:20 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:40160 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726191AbfDZSuU (ORCPT ); Fri, 26 Apr 2019 14:50:20 -0400 Received: from pps.filterd (m0044008.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x3QImuI5025391; Fri, 26 Apr 2019 11:49:59 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : mime-version : content-type : content-transfer-encoding; s=facebook; bh=EnjsEZWwcq81D5ESonNXLXlyLaFcXLKll3jlr23LZFs=; b=mBV+CbhnMusxXV+23NaKFI9dwxGKVOtWxfQPEE/7WMR0LbnRPIg3RzKggus2uxU34Hvf GlnFM1/f1CCcpUqT39V46JWGWDLwiajUM8NkQvkgWABZUKU0bvGX/SBJJ2cMonqd4IC6 P+bVVyhuWyAISlxtxqS5zsbWduZU3UTCVQU= Received: from mail.thefacebook.com (mailout.thefacebook.com [199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2s45aa0g72-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Fri, 26 Apr 2019 11:49:59 -0700 Received: from mmullins-1.thefacebook.com (2620:10d:c081:10::13) by mail.thefacebook.com (2620:10d:c081:35::125) with Microsoft SMTP Server id 15.1.1713.5; Fri, 26 Apr 2019 11:49:58 -0700 From: Matt Mullins To: , , , , CC: , Daniel Borkmann , Martin KaFai Lau , Song Liu , "Yonghong Song" Subject: [PATCH bpf-next v5 0/5] writable contexts for bpf raw tracepoints Date: Fri, 26 Apr 2019 11:49:46 -0700 Message-ID: <20190426184951.21812-1-mmullins@fb.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-Originating-IP: [2620:10d:c081:10::13] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-04-26_12:,, signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This adds an opt-in interface for tracepoints to expose a writable context to BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE programs that are attached, while supporting read-only access from existing BPF_PROG_TYPE_RAW_TRACEPOINT programs, as well as from non-BPF-based tracepoints. The initial motivation is to support tracing that can be observed from the remote end of an NBD socket, e.g. by adding flags to the struct nbd_request header. Earlier attempts included adding an NBD-specific tracepoint fd, but in code review, I was recommended to implement it more generically -- as a result, this patchset is far simpler than my initial try. v4->v5: * rebased onto bpf-next/master and fixed merge conflicts * "tools: sync bpf.h" also syncs comments that have previously changed in bpf-next v3->v4: * fixed a silly copy/paste typo in include/trace/events/bpf_test_run.h (_TRACE_NBD_H -> _TRACE_BPF_TEST_RUN_H) * fixed incorrect/misleading wording in patch 1's commit message, since the pointer cannot be directly dereferenced in a BPF_PROG_TYPE_RAW_TRACEPOINT * cleaned up the error message wording if the prog_tests fail * Addressed feedback from Yonghong * reject non-pointer-sized accesses to the buffer pointer * use sizeof(struct nbd_request) as one-byte-past-the-end in raw_tp_writable_reject_nbd_invalid.c * use BPF_MOV64_IMM instead of BPF_LD_IMM64 v2->v3: * Andrew addressed Josef's comments: * C-style commenting in nbd.c * Collapsed identical events into a single DECLARE_EVENT_CLASS. This saves about 2kB of kernel text v1->v2: * add selftests * sync tools/include/uapi/linux/bpf.h * reject variable offset into the buffer * add string representation of PTR_TO_TP_BUFFER to reg_type_str Andrew Hall (1): nbd: add tracepoints for send/receive timing Matt Mullins (4): bpf: add writable context for raw tracepoints nbd: trace sending nbd requests tools: sync bpf.h selftests: bpf: test writable buffers in raw tps MAINTAINERS | 1 + drivers/block/nbd.c | 13 +++ include/linux/bpf.h | 2 + include/linux/bpf_types.h | 1 + include/linux/tracepoint-defs.h | 1 + include/trace/bpf_probe.h | 27 ++++- include/trace/events/bpf_test_run.h | 50 ++++++++ include/trace/events/nbd.h | 107 ++++++++++++++++++ include/uapi/linux/bpf.h | 1 + kernel/bpf/syscall.c | 8 +- kernel/bpf/verifier.c | 31 +++++ kernel/trace/bpf_trace.c | 24 ++++ net/bpf/test_run.c | 4 + tools/include/uapi/linux/bpf.h | 10 +- tools/lib/bpf/libbpf.c | 1 + tools/lib/bpf/libbpf_probes.c | 1 + .../raw_tp_writable_reject_nbd_invalid.c | 42 +++++++ .../bpf/prog_tests/raw_tp_writable_test_run.c | 80 +++++++++++++ .../selftests/bpf/verifier/raw_tp_writable.c | 34 ++++++ 19 files changed, 433 insertions(+), 5 deletions(-) create mode 100644 include/trace/events/bpf_test_run.h create mode 100644 include/trace/events/nbd.h create mode 100644 tools/testing/selftests/bpf/prog_tests/raw_tp_writable_reject_nbd_invalid.c create mode 100644 tools/testing/selftests/bpf/prog_tests/raw_tp_writable_test_run.c create mode 100644 tools/testing/selftests/bpf/verifier/raw_tp_writable.c -- 2.17.1