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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ECAA8C00140 for ; Thu, 18 Aug 2022 23:27:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230183AbiHRX1d (ORCPT ); Thu, 18 Aug 2022 19:27:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37222 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241562AbiHRX1c (ORCPT ); Thu, 18 Aug 2022 19:27:32 -0400 Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 652C4D7593 for ; Thu, 18 Aug 2022 16:27:31 -0700 (PDT) Received: by mail-pj1-x104a.google.com with SMTP id r13-20020a17090a454d00b001f04dfc6195so1685615pjm.2 for ; Thu, 18 Aug 2022 16:27:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:from:to:cc; bh=9NL/MGm5AHq1wrzRe0O0SuxsMoLUiY6vUB/kSVtuDXQ=; b=gMyckusyqNV8cXVvgNCBl24tf6Fd9k6i756kvnQpSycCgpW6uggE/oZRZt4sXntJXL Uls32V7yxgCjrtWJ0xKanGRw2wYQZzHIVOwTZrSWR7CHRPti5eDNcR1cp9KiYWIXiuY2 TwsvNdvhMRP+f2DAfbvVF+W586kGFjzv8bBnn5zfTk4+ZDDdr79KK0OrvAqV/dGGokWF +XAQTKT1Sl1SEbu+cR/dITi8uXPY1SieiUomnxxYOYYhsnlEczxckay/OURsMtWEirva IlT9eaH9caLlhe3liDplYTk2pcKZ+iP+6ip3A3jlq3VAip6q6MMDvd1XRg5ZWQdLNXEj VC9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:x-gm-message-state :from:to:cc; bh=9NL/MGm5AHq1wrzRe0O0SuxsMoLUiY6vUB/kSVtuDXQ=; b=GYmnOtfDoSJHmpEVyS8DiC/QFcTq1Gi6dkVoNzwMXwn8UUKDTl6PpaS6S+78lRdgOQ 5EhZGOAEoVt3zzq7mvZ7Fngi1LN95S1JHX/rAZQYfA0TL/a3ZM2LtC9Xr//qXn60f811 YZl80KLJVUFsBhWBnZRRbVYXOGjCi/A0Dt/v83VKHp/DUBnZ09e/Zj5UaBFh/blNsGt4 yGToCmU0RwQfsi58C+3KkqVOHaeJa0f5mOQL7vsB0vZbLnsCsm9dyNIXMVSTB1Ag/gp0 qsB/OOI/r4ADCfKys2DmUdl2xeIFPYAlnPUYnlWQWakvws/yHz6NKop/LiZalrOemqXs rl2Q== X-Gm-Message-State: ACgBeo3hxkKC1b9axGV7feNxbq0g+lKtrbazYioY5EW8Wt9zoNmmG2ux LXKZRf77WY2WhK5NQl6PBnHAncycYT3nCDA8Ts2c/uNCxXViDwNiG0SKYpZ8lNeHjfYp56Gd8wq 9yvvYLftLdPVW4ftuFLq7kWNrs+TcVb4+lmLAU3Da/0X9KLud+Q== X-Google-Smtp-Source: AA6agR5s92Xgx+RScZX3QUYGuCIzPGuRsulr/092ujLQTQjcHZuvbn2GwwQZpiBanfRHewqX360KUiQ= X-Received: from sdf.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5935]) (user=sdf job=sendgmr) by 2002:a17:903:244c:b0:171:59be:6762 with SMTP id l12-20020a170903244c00b0017159be6762mr4541514pls.20.1660865250817; Thu, 18 Aug 2022 16:27:30 -0700 (PDT) Date: Thu, 18 Aug 2022 16:27:24 -0700 Message-Id: <20220818232729.2479330-1-sdf@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.37.1.595.g718a3a8f04-goog Subject: [PATCH bpf-next v3 0/5] bpf: expose bpf_{g,s}et_retval to more cgroup hooks From: Stanislav Fomichev To: bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Apparently, only a small subset of cgroup hooks actually falls back to cgroup_base_func_proto. This leads to unexpected result where not all cgroup helpers have bpf_{g,s}et_retval. It's getting harder and harder to manage which helpers are exported to which hooks. We now have the following call chains: - cg_skb_func_proto - sk_filter_func_proto - bpf_sk_base_func_proto - bpf_base_func_proto So by looking at cg_skb_func_proto it's pretty hard to understand what's going on. For cgroup helpers, I'm proposing we do the following instead: func_proto = cgroup_common_func_proto(); if (func_proto) return func_proto; /* optional, if hook has 'current' */ func_proto = cgroup_current_func_proto(); if (func_proto) return func_proto; ... switch (func_id) { /* hook specific helpers */ case BPF_FUNC_hook_specific_helper: return &xyz; default: /* always fall back to plain bpf_base_func_proto */ bpf_base_func_proto(func_id); } If this turns out more workable, we can follow up with converting the rest to the same pattern. v3: - expose strtol/strtoul everywhere (Martin) - move helpers declarations from bpf.h to bpf-cgroup.h (Martin) - revise bpf_{g,s}et_retval documentation (Martin) - don't expose bpf_{g,s}et_retval to cg_skb hooks (Martin) v2: - move everything into kernel/bpf/cgroup.c instead (Martin) - use cgroup_common_func_proto in lsm (Martin) Stanislav Fomichev (5): bpf: Introduce cgroup_{common,current}_func_proto bpf: Use cgroup_{common,current}_func_proto in more hooks bpf: expose bpf_strtol and bpf_strtoul to all program types bpf: update bpf_{g,s}et_retval documentation selftests/bpf: Make sure bpf_{g,s}et_retval is exposed everywhere include/linux/bpf-cgroup.h | 17 ++ include/uapi/linux/bpf.h | 22 +- kernel/bpf/bpf_lsm.c | 19 +- kernel/bpf/cgroup.c | 212 ++++++++++++++++-- kernel/bpf/helpers.c | 82 +------ net/core/filter.c | 92 +++----- tools/include/uapi/linux/bpf.h | 22 +- tools/testing/selftests/bpf/Makefile | 1 + .../bpf/cgroup_getset_retval_hooks.h | 25 +++ .../bpf/prog_tests/cgroup_getset_retval.c | 48 ++++ .../bpf/progs/cgroup_getset_retval_hooks.c | 16 ++ 11 files changed, 380 insertions(+), 176 deletions(-) create mode 100644 tools/testing/selftests/bpf/cgroup_getset_retval_hooks.h create mode 100644 tools/testing/selftests/bpf/progs/cgroup_getset_retval_hooks.c -- 2.37.1.595.g718a3a8f04-goog