From patchwork Thu Jan 26 23:34:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joanne Koong X-Patchwork-Id: 13117936 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 D7BE0C05027 for ; Fri, 27 Jan 2023 00:00:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230051AbjA0AAu (ORCPT ); Thu, 26 Jan 2023 19:00:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39438 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229459AbjA0AAt (ORCPT ); Thu, 26 Jan 2023 19:00:49 -0500 Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B46535A8 for ; Thu, 26 Jan 2023 16:00:48 -0800 (PST) Received: by devvm15675.prn0.facebook.com (Postfix, from userid 115148) id EF4954BA3634; Thu, 26 Jan 2023 15:38:24 -0800 (PST) From: Joanne Koong To: bpf@vger.kernel.org Cc: daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org, ast@kernel.org, netdev@vger.kernel.org, memxor@gmail.com, kernel-team@fb.com, Joanne Koong Subject: [PATCH v8 bpf-next 0/5] Add skb + xdp dynptrs Date: Thu, 26 Jan 2023 15:34:34 -0800 Message-Id: <20230126233439.3739120-1-joannelkoong@gmail.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This patchset is the 2nd in the dynptr series. The 1st can be found here [0]. This patchset adds skb and xdp type dynptrs, which have two main benefits for packet parsing: * allowing operations on sizes that are not statically known at compile-time (eg variable-sized accesses). * more ergonomic and less brittle iteration through data (eg does not need manual if checking for being within bounds of data_end) When comparing the differences in runtime for packet parsing without dynptrs vs. with dynptrs for the more simple cases, there is no noticeable difference. For the more complex cases where lengths are non-statically known at compile time, there can be a significant speed-up when using dynptrs (eg a 2x speed up for cls redirection). Patch 3 contains more details as well as examples of how to use skb and xdp dynptrs. [0] https://lore.kernel.org/bpf/20220523210712.3641569-1-joannelkoong@gmail.com/ --- Changelog: v7 = https://lore.kernel.org/bpf/20221021011510.1890852-1-joannelkoong@gmail.com/ v7 -> v8: * Change helpers to kfuncs * Add 2 new patches (1/5 and 2/5) v6 = https://lore.kernel.org/bpf/20220907183129.745846-1-joannelkoong@gmail.com/ v6 -> v7 * Change bpf_dynptr_data() to return read-only data slices if the skb prog is read-only (Martin) * Add test "skb_invalid_write" to test that writes to rd-only data slices are rejected v5 = https://lore.kernel.org/bpf/20220831183224.3754305-1-joannelkoong@gmail.com/ v5 -> v6 * Address kernel test robot errors by static inlining v4 = https://lore.kernel.org/bpf/20220822235649.2218031-1-joannelkoong@gmail.com/ v4 -> v5 * Address kernel test robot errors for configs w/out CONFIG_NET set * For data slices, return PTR_TO_MEM instead of PTR_TO_PACKET (Kumar) * Split selftests into subtests (Andrii) * Remove insn patching. Use rdonly and rdwr protos for dynptr skb construction (Andrii) * bpf_dynptr_data() returns NULL for rd-only dynptrs. There will be a separate bpf_dynptr_data_rdonly() added later (Andrii and Kumar) v3 = https://lore.kernel.org/bpf/20220822193442.657638-1-joannelkoong@gmail.com/ v3 -> v4 * Forgot to commit --amend the kernel test robot error fixups v2 = https://lore.kernel.org/bpf/20220811230501.2632393-1-joannelkoong@gmail.com/ v2 -> v3 * Fix kernel test robot build test errors v1 = https://lore.kernel.org/bpf/20220726184706.954822-1-joannelkoong@gmail.com/ v1 -> v2 * Return data slices to rd-only skb dynptrs (Martin) * bpf_dynptr_write allows writes to frags for skb dynptrs, but always invalidates associated data slices (Martin) * Use switch casing instead of ifs (Andrii) * Use 0xFD for experimental kind number in the selftest (Zvi) * Put selftest conversions w/ dynptrs into new files (Alexei) * Add new selftest "test_cls_redirect_dynptr.c" Joanne Koong (5): bpf: Allow "sk_buff" and "xdp_buff" as valid kfunc arg types bpf: Allow initializing dynptrs in kfuncs bpf: Add skb dynptrs bpf: Add xdp dynptrs selftests/bpf: tests for using dynptrs to parse skb and xdp buffers include/linux/bpf.h | 88 +- include/linux/bpf_verifier.h | 3 - include/linux/filter.h | 38 + include/uapi/linux/bpf.h | 41 +- kernel/bpf/btf.c | 22 + kernel/bpf/helpers.c | 107 +- kernel/bpf/verifier.c | 325 +++--- net/core/filter.c | 104 +- tools/include/uapi/linux/bpf.h | 41 +- .../selftests/bpf/prog_tests/cls_redirect.c | 25 + .../testing/selftests/bpf/prog_tests/dynptr.c | 63 +- .../selftests/bpf/prog_tests/l4lb_all.c | 2 + .../bpf/prog_tests/parse_tcp_hdr_opt.c | 93 ++ .../selftests/bpf/prog_tests/xdp_attach.c | 11 +- .../testing/selftests/bpf/progs/dynptr_fail.c | 124 +++ .../selftests/bpf/progs/dynptr_success.c | 28 + .../bpf/progs/test_cls_redirect_dynptr.c | 973 ++++++++++++++++++ .../bpf/progs/test_l4lb_noinline_dynptr.c | 474 +++++++++ .../bpf/progs/test_parse_tcp_hdr_opt.c | 119 +++ .../bpf/progs/test_parse_tcp_hdr_opt_dynptr.c | 112 ++ .../selftests/bpf/progs/test_xdp_dynptr.c | 237 +++++ .../selftests/bpf/test_tcp_hdr_options.h | 1 + 22 files changed, 2825 insertions(+), 206 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/parse_tcp_hdr_opt.c create mode 100644 tools/testing/selftests/bpf/progs/test_cls_redirect_dynptr.c create mode 100644 tools/testing/selftests/bpf/progs/test_l4lb_noinline_dynptr.c create mode 100644 tools/testing/selftests/bpf/progs/test_parse_tcp_hdr_opt.c create mode 100644 tools/testing/selftests/bpf/progs/test_parse_tcp_hdr_opt_dynptr.c create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_dynptr.c