From patchwork Thu Apr 20 07:26:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Feng Zhou X-Patchwork-Id: 13218028 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 58545C77B73 for ; Thu, 20 Apr 2023 07:28:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234083AbjDTH2D (ORCPT ); Thu, 20 Apr 2023 03:28:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234076AbjDTH2C (ORCPT ); Thu, 20 Apr 2023 03:28:02 -0400 Received: from mail-pg1-x530.google.com (mail-pg1-x530.google.com [IPv6:2607:f8b0:4864:20::530]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1A84B10D8 for ; Thu, 20 Apr 2023 00:27:19 -0700 (PDT) Received: by mail-pg1-x530.google.com with SMTP id 41be03b00d2f7-51b5490c6f0so638421a12.0 for ; Thu, 20 Apr 2023 00:27:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1681975638; x=1684567638; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=6AGDNBCroQ67ha7RBjKHaMJL6Jfwc8C2hS0pEsm+v2A=; b=OpSJ3fP8ohLBcF5v5MU5Rjik38xw5j2zLix4CDhL8qi3Fcc9Lp3haSVTs4u/Qi4Zsl hgjdGVRaLRxpOzn+r5mH/4godg3oJwPY6ozMKTjkZ41kbNqzaAfp1Zl+F+YhY8bPWjlg IhUf5LhT0ruVsyMuCH6Nvg8VIKPKH7wNGdopgQzjUUocPrFrUd74+kbaC/kobzz4T9OS b/CX5e0gDKgOrga5AFlkMu22zwDCComdkjGEGcDpdHYBGsP8QWNgqEFaDW9OelrTTpjN 9VbL9NNmfrMEwf9PBx0G+xAqirzA6ynLKLX/zO7M/jbl/VshrsjaAX/qD10YYqLj33LA iHKw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681975638; x=1684567638; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=6AGDNBCroQ67ha7RBjKHaMJL6Jfwc8C2hS0pEsm+v2A=; b=FpMjPz+wkgbTE8ErkPgdXiMrVggSASSTlTh0ynpt8GUEmIgZ0JzM4DXuG/7V3kaoO2 w+auo7qk2AgDDc4knhPSGa72D6Qj1FS31Wo14CUsvDNQqC0YvoGfOT32pU72ivxq2H7g G8oNcSafuHiJ+JuKBS+2Z5hj1JwZBvV4cMdBZtnOLFQvRdPd8oGlzw9nFpCf/kNCKt2A j85KfHddRGd28EL6Br8yXCiCSNRFEE6lLPa2QoGauWks0mRCVier6qzDcj7HuZ3M1psL MVRsR9Pgnpz5xhTNtuJCyhXgfHzVS//d/rhNKlGAF63dD04GPyPCFtYudeLMa7Gyk9Nf vhyA== X-Gm-Message-State: AAQBX9cXkvY6T2xDLntDfB7ANZN0zprnWbj1ixlG4vM+xkXv6fIc66o9 Vh7IQip5p91tmT7TKE9ku15FSA== X-Google-Smtp-Source: AKy350ZFPlMmLIgo3dxD8Pjx/iOi0QJD5dfUllNmEoK8su1FQZkDUKeJ8zu4ovXLU4A8WJNAFZUQsA== X-Received: by 2002:a17:90a:2cc1:b0:247:48a1:3fb2 with SMTP id n59-20020a17090a2cc100b0024748a13fb2mr826552pjd.19.1681975638511; Thu, 20 Apr 2023 00:27:18 -0700 (PDT) Received: from C02F52LSML85.bytedance.net ([139.177.225.238]) by smtp.gmail.com with ESMTPSA id y18-20020a17090ad71200b0023440af7aafsm612160pju.9.2023.04.20.00.27.11 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 20 Apr 2023 00:27:18 -0700 (PDT) From: Feng zhou To: martin.lau@linux.dev, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, mykolal@fb.com, shuah@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, yangzhenze@bytedance.com, wangdongdong.6@bytedance.com, zhoufeng.zf@bytedance.com Subject: [PATCH bpf-next 1/2] bpf: Add bpf_task_under_cgroup helper Date: Thu, 20 Apr 2023 15:26:56 +0800 Message-Id: <20230420072657.80324-2-zhoufeng.zf@bytedance.com> X-Mailer: git-send-email 2.39.2 (Apple Git-143) In-Reply-To: <20230420072657.80324-1-zhoufeng.zf@bytedance.com> References: <20230420072657.80324-1-zhoufeng.zf@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Feng Zhou This adds a bpf helper that's similar to the bpf_current_task_under_cgroup. The difference is that it is a designated task. When hook sched related functions, sometimes it is necessary to specify a task instead of the current task. Signed-off-by: Feng Zhou --- include/uapi/linux/bpf.h | 13 +++++++++++++ kernel/bpf/verifier.c | 4 +++- kernel/trace/bpf_trace.c | 31 +++++++++++++++++++++++++++++++ tools/include/uapi/linux/bpf.h | 13 +++++++++++++ 4 files changed, 60 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 4b20a7269bee..3d31ddb39e10 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -5550,6 +5550,18 @@ union bpf_attr { * 0 on success. * * **-ENOENT** if the bpf_local_storage cannot be found. + * + * long bpf_task_under_cgroup(struct bpf_map *map, struct task_struct *task, u32 index) + * Description + * Check whether the probe is being run is the context of a given + * subset of the cgroup2 hierarchy. The cgroup2 to test is held by + * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*. + * Return + * The return value depends on the result of the test, and can be: + * + * * 1, if assigned task belongs to the cgroup2. + * * 0, if assigned task does not belong to the cgroup2. + * * A negative error code, if an error occurred. */ #define ___BPF_FUNC_MAPPER(FN, ctx...) \ FN(unspec, 0, ##ctx) \ @@ -5764,6 +5776,7 @@ union bpf_attr { FN(user_ringbuf_drain, 209, ##ctx) \ FN(cgrp_storage_get, 210, ##ctx) \ FN(cgrp_storage_delete, 211, ##ctx) \ + FN(task_under_cgroup, 212, ##ctx) \ /* */ /* backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 1e05355facdc..1e2c3c3e8d5f 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7771,7 +7771,8 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, break; case BPF_MAP_TYPE_CGROUP_ARRAY: if (func_id != BPF_FUNC_skb_under_cgroup && - func_id != BPF_FUNC_current_task_under_cgroup) + func_id != BPF_FUNC_current_task_under_cgroup && + func_id != BPF_FUNC_task_under_cgroup) goto error; break; case BPF_MAP_TYPE_CGROUP_STORAGE: @@ -7902,6 +7903,7 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, goto error; break; case BPF_FUNC_current_task_under_cgroup: + case BPF_FUNC_task_under_cgroup: case BPF_FUNC_skb_under_cgroup: if (map->map_type != BPF_MAP_TYPE_CGROUP_ARRAY) goto error; diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index bcf91bc7bf71..b02a04768824 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -814,6 +814,35 @@ static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = { .arg2_type = ARG_ANYTHING, }; +BPF_CALL_3(bpf_task_under_cgroup, struct bpf_map *, map, struct task_struct *, + task, u32, idx) +{ + struct bpf_array *array = container_of(map, struct bpf_array, map); + struct cgroup *cgrp; + + if (unlikely(!task)) + return -ENOENT; + + if (unlikely(idx >= array->map.max_entries)) + return -E2BIG; + + cgrp = READ_ONCE(array->ptrs[idx]); + if (unlikely(!cgrp)) + return -EAGAIN; + + return task_under_cgroup_hierarchy(task, cgrp); +} + +static const struct bpf_func_proto bpf_task_under_cgroup_proto = { + .func = bpf_task_under_cgroup, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_CONST_MAP_PTR, + .arg2_type = ARG_PTR_TO_BTF_ID, + .arg2_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK], + .arg3_type = ARG_ANYTHING, +}; + struct send_signal_irq_work { struct irq_work irq_work; struct task_struct *task; @@ -1510,6 +1539,8 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_find_vma_proto; case BPF_FUNC_trace_vprintk: return bpf_get_trace_vprintk_proto(); + case BPF_FUNC_task_under_cgroup: + return &bpf_task_under_cgroup_proto; default: return bpf_base_func_proto(func_id); } diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 4b20a7269bee..3d31ddb39e10 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5550,6 +5550,18 @@ union bpf_attr { * 0 on success. * * **-ENOENT** if the bpf_local_storage cannot be found. + * + * long bpf_task_under_cgroup(struct bpf_map *map, struct task_struct *task, u32 index) + * Description + * Check whether the probe is being run is the context of a given + * subset of the cgroup2 hierarchy. The cgroup2 to test is held by + * *map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*. + * Return + * The return value depends on the result of the test, and can be: + * + * * 1, if assigned task belongs to the cgroup2. + * * 0, if assigned task does not belong to the cgroup2. + * * A negative error code, if an error occurred. */ #define ___BPF_FUNC_MAPPER(FN, ctx...) \ FN(unspec, 0, ##ctx) \ @@ -5764,6 +5776,7 @@ union bpf_attr { FN(user_ringbuf_drain, 209, ##ctx) \ FN(cgrp_storage_get, 210, ##ctx) \ FN(cgrp_storage_delete, 211, ##ctx) \ + FN(task_under_cgroup, 212, ##ctx) \ /* */ /* backwards-compatibility macros for users of __BPF_FUNC_MAPPER that don't From patchwork Thu Apr 20 07:26:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Feng Zhou X-Patchwork-Id: 13218027 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 C4671C77B73 for ; Thu, 20 Apr 2023 07:27:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234067AbjDTH1f (ORCPT ); Thu, 20 Apr 2023 03:27:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234068AbjDTH12 (ORCPT ); Thu, 20 Apr 2023 03:27:28 -0400 Received: from mail-pl1-x631.google.com (mail-pl1-x631.google.com [IPv6:2607:f8b0:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 160914EEC for ; Thu, 20 Apr 2023 00:27:27 -0700 (PDT) Received: by mail-pl1-x631.google.com with SMTP id d9443c01a7336-1a66b9bd893so7586965ad.1 for ; Thu, 20 Apr 2023 00:27:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1681975646; x=1684567646; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=KY6KaCFZ5vdzzIXTUyV6D8NEGya8RvpCjdxKUFkIlbo=; b=JdpK091tQZhcpVQCrGmT53jyzk0tdpPMrMjsOt2nhOO6VvJm4CHj6b3MGcEtFPjrmj jRNPw5HUcEZWIJGHvsLxe344JI6DV18Gtby29KPcbI49o3qCSmqB71Eg+4RPCbqs4iPm v3YHKLR5mv2ycE2z5Uzvthf87ASaR/OaOaKaMkZbPpGN/o1brGSdxKSc6IochSv6/AbZ gDpcAdKFTBC8fGCg660IDSJI/tyA2ywbL5RjXTgpq/uufdxPrCODT/WuDOdKNukitBLv z7znofi2TQ82y2kjpWhFiI7HRNVKU1n6s9umJI6PADeGkDWPZdOKeULaonHTZo5nIUD8 LGig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681975646; x=1684567646; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=KY6KaCFZ5vdzzIXTUyV6D8NEGya8RvpCjdxKUFkIlbo=; b=cQtEVdGOaAbvxyIkfnSKPRVGZf7CfO7072r1BCrMa0fmMoxHQg0CR+JdL4wd/j6paN wjt8ca3/QV3B6D2GhQstpmyNZj4EUZV8yHayg3rRdsTARDmJl14XlR8N6PnvVF6liYBD hmflyYHZHk6hq9j27h5By8/iU6Abel1luWFsGiT5UbrAopQ4SyNlrbCVjF1VYmclIRHk NZ4BKnHqDT4zYthmb3M+EC6OGoRVB425mSn7VPHEpV737R7HPx9b4A+uWp8CVQtvXLyv 593aKq09fzlvClo2Rn6LpW6t1mxtvluYEIe13s7EEWqy++yCpwunzv43YOg0jGPUvl+5 DbAQ== X-Gm-Message-State: AAQBX9fvAO5lD9JpVKn4hfLIslcjwDlQ4tMluNuF3k8VrjLg4Gv5N+M3 ASF7gqe7Q6rU9ZS+fCSE+4lFTA== X-Google-Smtp-Source: AKy350Zh/YeQnWj7L0LszMWL1n63Iez1x6ZInscmr5n73w2GM1PRAMnrQpIboMm8xj558lZf9TY4Gg== X-Received: by 2002:a17:90a:d381:b0:249:7958:ea36 with SMTP id q1-20020a17090ad38100b002497958ea36mr847077pju.19.1681975646451; Thu, 20 Apr 2023 00:27:26 -0700 (PDT) Received: from C02F52LSML85.bytedance.net ([139.177.225.238]) by smtp.gmail.com with ESMTPSA id y18-20020a17090ad71200b0023440af7aafsm612160pju.9.2023.04.20.00.27.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 20 Apr 2023 00:27:26 -0700 (PDT) From: Feng zhou To: martin.lau@linux.dev, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, mykolal@fb.com, shuah@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, yangzhenze@bytedance.com, wangdongdong.6@bytedance.com, zhoufeng.zf@bytedance.com Subject: [PATCH bpf-next 2/2] selftests/bpf: Add testcase for bpf_task_under_cgroup Date: Thu, 20 Apr 2023 15:26:57 +0800 Message-Id: <20230420072657.80324-3-zhoufeng.zf@bytedance.com> X-Mailer: git-send-email 2.39.2 (Apple Git-143) In-Reply-To: <20230420072657.80324-1-zhoufeng.zf@bytedance.com> References: <20230420072657.80324-1-zhoufeng.zf@bytedance.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Feng Zhou test_progs: Tests new ebpf helpers bpf_task_under_cgroup. The bpf program saves the pid which call the getuid syscall within a given cgroup to a map to the remote_pid, which is convenient for the user-mode program to verify the test correctness. The user-mode program creates its own mount namespace, and mounts the cgroupsv2 hierarchy in there, call the getuid syscall, then check if remote_pid and local_pid are equal. Signed-off-by: Feng Zhou --- .../bpf/prog_tests/task_under_cgroup.c | 49 +++++++++++++++++++ .../bpf/progs/test_task_under_cgroup.c | 31 ++++++++++++ 2 files changed, 80 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c create mode 100644 tools/testing/selftests/bpf/progs/test_task_under_cgroup.c diff --git a/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c new file mode 100644 index 000000000000..4dd704b11a95 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c @@ -0,0 +1,49 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Bytedance */ + +#include +#include "test_task_under_cgroup.skel.h" + +#define FOO "/foo" + +void test_task_under_cgroup(void) +{ + struct test_task_under_cgroup *skel; + int ret, foo = -1, idx = 0; + + skel = test_task_under_cgroup__open(); + if (!ASSERT_OK_PTR(skel, "test_task_under_cgroup__open")) + return; + + skel->rodata->local_pid = getpid(); + + ret = test_task_under_cgroup__load(skel); + if (!ASSERT_OK(ret, "test_task_under_cgroup__load")) + goto cleanup; + + ret = test_task_under_cgroup__attach(skel); + if (!ASSERT_OK(ret, "test_task_under_cgroup__attach")) + goto cleanup; + + foo = test__join_cgroup(FOO); + if (!ASSERT_OK(foo < 0, "cgroup_join_foo")) + goto cleanup; + + ret = bpf_map_update_elem(bpf_map__fd(skel->maps.cgroup_map), &idx, + &foo, BPF_ANY); + if (!ASSERT_OK(ret < 0, "cgroup_map update")) + goto cleanup; + + syscall(__NR_getuid); + + test_task_under_cgroup__detach(skel); + + ASSERT_EQ(skel->bss->remote_pid, skel->rodata->local_pid, + "test task_under_cgroup"); + +cleanup: + if (foo) + close(foo); + + test_task_under_cgroup__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c new file mode 100644 index 000000000000..0f3d53f636de --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c @@ -0,0 +1,31 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2023 Bytedance */ + +#include "vmlinux.h" +#include + +const volatile int local_pid; +int remote_pid; + +struct { + __uint(type, BPF_MAP_TYPE_CGROUP_ARRAY); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u32); +} cgroup_map SEC(".maps"); + +SEC("tp/syscalls/sys_enter_getuid") +int sysenter_getuid(const void *ctx) +{ + if (local_pid != (bpf_get_current_pid_tgid() >> 32)) + return 0; + + if (!bpf_task_under_cgroup(&cgroup_map, bpf_get_current_task_btf(), 0)) + return 0; + + remote_pid = local_pid; + + return 0; +} + +char _license[] SEC("license") = "GPL";