From patchwork Fri Jul 31 18:28:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1339540 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=reject dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.a=rsa-sha256 header.s=facebook header.b=VUKziRaC; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BJG4k09Thz9sT6 for ; Sat, 1 Aug 2020 04:28:38 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387887AbgGaS2h (ORCPT ); Fri, 31 Jul 2020 14:28:37 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:58346 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387680AbgGaS2h (ORCPT ); Fri, 31 Jul 2020 14:28:37 -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 06VIFkBd023635 for ; Fri, 31 Jul 2020 11:28:36 -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-transfer-encoding : content-type; s=facebook; bh=KqJIq725uq/HnQgvV55bIPsHwEMCXKUIsjnJYCPw/KY=; b=VUKziRaCkW0C976VR373ufk0F457N/CZ1hgiR8/PvuX6nAfrB6iflE9taDrVzuQSvCzo vMr0SpR7EYe4J1lUgoxyqsfcDECO+MNPbwsgeSvHxW5ctdzhPoyN0jsb+CPzH4uelDig tezzZsI0jDXj36JBiAOx/D5XGutD4rRND5k= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 32kcbv3m6h-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Fri, 31 Jul 2020 11:28:36 -0700 Received: from intmgw003.03.ash8.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::e) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Fri, 31 Jul 2020 11:28:34 -0700 Received: by devbig012.ftw2.facebook.com (Postfix, from userid 137359) id D16682EC4E02; Fri, 31 Jul 2020 11:28:31 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Andrii Nakryiko Smtp-Origin-Hostname: devbig012.ftw2.facebook.com To: , , , CC: , , Andrii Nakryiko Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH v2 bpf-next 0/5] BPF link force-detach support Date: Fri, 31 Jul 2020 11:28:25 -0700 Message-ID: <20200731182830.286260-1-andriin@fb.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-07-31_07:2020-07-31,2020-07-31 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxlogscore=689 bulkscore=0 clxscore=1015 suspectscore=8 phishscore=0 malwarescore=0 priorityscore=1501 adultscore=0 spamscore=0 impostorscore=0 mlxscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007310137 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch set adds new BPF link operation, LINK_DETACH, allowing processes with BPF link FD to force-detach it from respective BPF hook, similarly how BPF link is auto-detached when such BPF hook (e.g., cgroup, net_device, netns, etc) is removed. This facility allows admin to forcefully undo BPF link attachment, while process that created BPF link in the first place is left intact. Once force-detached, BPF link stays valid in the kernel as long as there is at least one FD open against it. It goes into defunct state, just like auto-detached BPF link. bpftool also got `link detach` command to allow triggering this in non-programmatic fashion. v1->v2: - improve error reporting in `bpftool link detach` (Song). Andrii Nakryiko (5): bpf: add support for forced LINK_DETACH command libbpf: add bpf_link detach APIs selftests/bpf: add link detach tests for cgroup, netns, and xdp bpf_links tools/bpftool: add `link detach` subcommand tools/bpftool: add documentation and bash-completion for `link detach` include/linux/bpf.h | 1 + include/uapi/linux/bpf.h | 5 ++ kernel/bpf/cgroup.c | 15 +++++- kernel/bpf/net_namespace.c | 8 +++ kernel/bpf/syscall.c | 26 ++++++++++ net/core/dev.c | 11 +++- .../bpftool/Documentation/bpftool-link.rst | 8 +++ tools/bpf/bpftool/bash-completion/bpftool | 4 +- tools/bpf/bpftool/link.c | 37 +++++++++++++- tools/include/uapi/linux/bpf.h | 5 ++ tools/lib/bpf/bpf.c | 10 ++++ tools/lib/bpf/bpf.h | 2 + tools/lib/bpf/libbpf.c | 5 ++ tools/lib/bpf/libbpf.h | 1 + tools/lib/bpf/libbpf.map | 2 + .../selftests/bpf/prog_tests/cgroup_link.c | 20 +++++++- .../selftests/bpf/prog_tests/sk_lookup.c | 51 +++++++++---------- .../selftests/bpf/prog_tests/xdp_link.c | 14 +++++ tools/testing/selftests/bpf/testing_helpers.c | 14 +++++ tools/testing/selftests/bpf/testing_helpers.h | 3 ++ 20 files changed, 208 insertions(+), 34 deletions(-)