From patchwork Fri Sep 23 06:06:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Marchevsky X-Patchwork-Id: 12986150 X-Patchwork-Delegate: bpf@iogearbox.net 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 23B6BC6FA82 for ; Fri, 23 Sep 2022 06:06:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229744AbiIWGGY (ORCPT ); Fri, 23 Sep 2022 02:06:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46008 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229900AbiIWGGW (ORCPT ); Fri, 23 Sep 2022 02:06:22 -0400 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DECA4115F4F for ; Thu, 22 Sep 2022 23:06:21 -0700 (PDT) Received: from pps.filterd (m0109334.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 28MKiQlg001103 for ; Thu, 22 Sep 2022 23:06:21 -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=FIa3Yq6n+zpZVVx7wdnOb8Y0bW8rXKBDQLxFsBYeCqg=; b=EO9ZkImL2kJ4DTybOli8pC8OLWn6UnpFVBNticCXKjWf2HVrVVgstrTEdQnhg8GbNVqz fYSgziTO0c64MdtigkKQui3oGIh0Z4dC5+XweVBDVALBYc9ji8OCwL8hslLhv7lrrFMB BxU3m+7r+ke7I7LQHZCpEhSxaqoIvNhY8Y4= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3jrhjgrj85-3 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 22 Sep 2022 23:06:21 -0700 Received: from twshared3888.09.ash9.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::d) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 22 Sep 2022 23:06:18 -0700 Received: by devbig077.ldc1.facebook.com (Postfix, from userid 158236) id B495DDE1C3D6; Thu, 22 Sep 2022 23:06:16 -0700 (PDT) From: Dave Marchevsky To: CC: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Kernel Team , Kumar Kartikeya Dwivedi , Yonghong Song , Dave Marchevsky Subject: [PATCH v4 bpf-next 1/2] bpf: Allow ringbuf memory to be used as map key Date: Thu, 22 Sep 2022 23:06:13 -0700 Message-ID: <20220923060614.4025371-1-davemarchevsky@fb.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: OlcdaPvLOjBCDFEfZBlBqNtnrt9Z0qg9 X-Proofpoint-ORIG-GUID: OlcdaPvLOjBCDFEfZBlBqNtnrt9Z0qg9 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.528,FMLib:17.11.122.1 definitions=2022-09-23_02,2022-09-22_02,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This patch adds support for the following pattern: struct some_data *data = bpf_ringbuf_reserve(&ringbuf, sizeof(struct some_data, 0)); if (!data) return; bpf_map_lookup_elem(&another_map, &data->some_field); bpf_ringbuf_submit(data); Currently the verifier does not consider bpf_ringbuf_reserve's PTR_TO_MEM | MEM_ALLOC ret type a valid key input to bpf_map_lookup_elem. Since PTR_TO_MEM is by definition a valid region of memory, it is safe to use it as a key for lookups. Signed-off-by: Dave Marchevsky Acked-by: Yonghong Song --- v2->v3: lore.kernel.org/bpf/20220914123600.927632-1-davemarchevsky@fb.com * Add Yonghong ack, rebase v1->v2: lore.kernel.org/bpf/20220912101106.2765921-1-davemarchevsky@fb.com * Move test changes into separate patch - patch 2 in this series. (Kumar, Yonghong). That patch's changelog enumerates specific changes from v1 * Remove PTR_TO_MEM addition from this patch - patch 1 (Yonghong) * I don't have a usecase for PTR_TO_MEM w/o MEM_ALLOC * Add "if (!data)" error check to example pattern in this patch (Yonghong) * Remove patch 2 from v1's series, which removed map_key_value_types as it was more-or-less duplicate of mem_types * Now that PTR_TO_MEM isn't added here, more differences between map_key_value_types and mem_types, and no usecase for PTR_TO_BUF, so drop for now. kernel/bpf/verifier.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 6f6d2d511c06..97351ae3e7a7 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5641,6 +5641,7 @@ static const struct bpf_reg_types map_key_value_types = { PTR_TO_PACKET_META, PTR_TO_MAP_KEY, PTR_TO_MAP_VALUE, + PTR_TO_MEM | MEM_ALLOC, }, }; From patchwork Fri Sep 23 06:06:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Marchevsky X-Patchwork-Id: 12986151 X-Patchwork-Delegate: bpf@iogearbox.net 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 1A225ECAAD8 for ; Fri, 23 Sep 2022 06:06:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229749AbiIWGG1 (ORCPT ); Fri, 23 Sep 2022 02:06:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46032 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229900AbiIWGG0 (ORCPT ); Fri, 23 Sep 2022 02:06:26 -0400 Received: from mx0a-00082601.pphosted.com (mx0a-00082601.pphosted.com [67.231.145.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E537115F52 for ; Thu, 22 Sep 2022 23:06:25 -0700 (PDT) Received: from pps.filterd (m0109333.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 28MKirYk027903 for ; Thu, 22 Sep 2022 23:06:25 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=facebook; bh=X9WK+USyP9MbmA4lH59or6RxvmRk4M/D2aL7ZUV5GSc=; b=oRUtvMs9DMOMMux4zmodzR3RdE6eZwXtAZ1Uv+00rnnJUi4cbMs16bpEaZ3I5v417euL YdsUAg5e2D9X8A2k89eDiqUFzvBC3o1njtaXl3TqEsqY1Hvy0c8j3hhbl8yM53R2xCeJ MVjsCBzTZX2bOpslnEjVmOxI6TzLZF96Lk8= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com (PPS) with ESMTPS id 3jrpfvy3ah-6 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 22 Sep 2022 23:06:25 -0700 Received: from twshared14494.08.ash8.facebook.com (2620:10d:c085:108::8) by mail.thefacebook.com (2620:10d:c085:11d::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 22 Sep 2022 23:06:24 -0700 Received: by devbig077.ldc1.facebook.com (Postfix, from userid 158236) id 5DF5BDE1C3E5; Thu, 22 Sep 2022 23:06:17 -0700 (PDT) From: Dave Marchevsky To: CC: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Kernel Team , Kumar Kartikeya Dwivedi , Yonghong Song , Dave Marchevsky Subject: [PATCH v4 bpf-next 2/2] selftests/bpf: Add test verifying bpf_ringbuf_reserve retval use in map ops Date: Thu, 22 Sep 2022 23:06:14 -0700 Message-ID: <20220923060614.4025371-2-davemarchevsky@fb.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220923060614.4025371-1-davemarchevsky@fb.com> References: <20220923060614.4025371-1-davemarchevsky@fb.com> MIME-Version: 1.0 X-FB-Internal: Safe X-Proofpoint-GUID: quG0U5l5AqmIWDXJSu9WOrOcyvgAnFJu X-Proofpoint-ORIG-GUID: quG0U5l5AqmIWDXJSu9WOrOcyvgAnFJu X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.528,FMLib:17.11.122.1 definitions=2022-09-23_02,2022-09-22_02,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add a test_ringbuf_map_key test prog, borrowing heavily from extant test_ringbuf.c. The program tries to use the result of bpf_ringbuf_reserve as map_key, which was not possible before previouis commits in this series. The test runner added to prog_tests/ringbuf.c verifies that the program loads and does basic sanity checks to confirm that it runs as expected. Also, refactor test_ringbuf such that runners for existing test_ringbuf and newly-added test_ringbuf_map_key are subtests of 'ringbuf' top-level test. Signed-off-by: Dave Marchevsky Acked-by: Yonghong Song --- v3->v4: lore.kernel.org/bpf/20220922142208.3009672-2-davemarchevsky@fb.com * Fix some nits (Yonghong) * make subtest runner functions static * don't goto cleanup if -EDONE check fails * add 'workaround' to comment in test to ease future grepping * Add Yonghong ack v2->v3: lore.kernel.org/bpf/20220914123600.927632-2-davemarchevsky@fb.com * Test that ring_buffer__poll returns -EDONE (Alexei) v1->v2: lore.kernel.org/bpf/20220912101106.2765921-1-davemarchevsky@fb.com * Actually run the program instead of just loading (Yonghong) * Add a bpf_map_update_elem call to the test (Yonghong) * Refactor runner such that existing test and newly-added test are subtests of 'ringbuf' top-level test (Yonghong) * Remove unused globals in test prog (Yonghong) tools/testing/selftests/bpf/Makefile | 8 ++- .../selftests/bpf/prog_tests/ringbuf.c | 64 ++++++++++++++++- .../bpf/progs/test_ringbuf_map_key.c | 71 +++++++++++++++++++ 3 files changed, 139 insertions(+), 4 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/test_ringbuf_map_key.c diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 5898d3828b82..28bd482f34a1 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -358,9 +358,11 @@ LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \ test_subskeleton.skel.h test_subskeleton_lib.skel.h \ test_usdt.skel.h -LSKELS := fentry_test.c fexit_test.c fexit_sleep.c \ - test_ringbuf.c atomics.c trace_printk.c trace_vprintk.c \ - map_ptr_kern.c core_kern.c core_kern_overflow.c +LSKELS := fentry_test.c fexit_test.c fexit_sleep.c atomics.c \ + trace_printk.c trace_vprintk.c map_ptr_kern.c \ + core_kern.c core_kern_overflow.c test_ringbuf.c \ + test_ringbuf_map_key.c + # Generate both light skeleton and libbpf skeleton for these LSKELS_EXTRA := test_ksyms_module.c test_ksyms_weak.c kfunc_call_test.c \ kfunc_call_test_subprog.c diff --git a/tools/testing/selftests/bpf/prog_tests/ringbuf.c b/tools/testing/selftests/bpf/prog_tests/ringbuf.c index 9a80fe8a6427..8c7d1467696c 100644 --- a/tools/testing/selftests/bpf/prog_tests/ringbuf.c +++ b/tools/testing/selftests/bpf/prog_tests/ringbuf.c @@ -13,6 +13,7 @@ #include #include #include "test_ringbuf.lskel.h" +#include "test_ringbuf_map_key.lskel.h" #define EDONE 7777 @@ -58,6 +59,7 @@ static int process_sample(void *ctx, void *data, size_t len) } } +static struct test_ringbuf_map_key_lskel *skel_map_key; static struct test_ringbuf_lskel *skel; static struct ring_buffer *ringbuf; @@ -81,7 +83,7 @@ static void *poll_thread(void *input) return (void *)(long)ring_buffer__poll(ringbuf, timeout); } -void test_ringbuf(void) +static void ringbuf_subtest(void) { const size_t rec_sz = BPF_RINGBUF_HDR_SZ + sizeof(struct sample); pthread_t thread; @@ -297,3 +299,63 @@ void test_ringbuf(void) ring_buffer__free(ringbuf); test_ringbuf_lskel__destroy(skel); } + +static int process_map_key_sample(void *ctx, void *data, size_t len) +{ + struct sample *s; + int err, val; + + s = data; + switch (s->seq) { + case 1: + ASSERT_EQ(s->value, 42, "sample_value"); + err = bpf_map_lookup_elem(skel_map_key->maps.hash_map.map_fd, + s, &val); + ASSERT_OK(err, "hash_map bpf_map_lookup_elem"); + ASSERT_EQ(val, 1, "hash_map val"); + return -EDONE; + default: + return 0; + } +} + +static void ringbuf_map_key_subtest(void) +{ + int err; + + skel_map_key = test_ringbuf_map_key_lskel__open(); + if (!ASSERT_OK_PTR(skel_map_key, "test_ringbuf_map_key_lskel__open")) + return; + + skel_map_key->maps.ringbuf.max_entries = getpagesize(); + skel_map_key->bss->pid = getpid(); + + err = test_ringbuf_map_key_lskel__load(skel_map_key); + if (!ASSERT_OK(err, "test_ringbuf_map_key_lskel__load")) + goto cleanup; + + ringbuf = ring_buffer__new(skel_map_key->maps.ringbuf.map_fd, + process_map_key_sample, NULL, NULL); + + err = test_ringbuf_map_key_lskel__attach(skel_map_key); + if (!ASSERT_OK(err, "test_ringbuf_map_key_lskel__attach")) + goto cleanup_ringbuf; + + syscall(__NR_getpgid); + ASSERT_EQ(skel_map_key->bss->seq, 1, "skel_map_key->bss->seq"); + err = ring_buffer__poll(ringbuf, -1); + ASSERT_EQ(err, -EDONE, "ring_buffer__poll"); + +cleanup_ringbuf: + ring_buffer__free(ringbuf); +cleanup: + test_ringbuf_map_key_lskel__destroy(skel_map_key); +} + +void test_ringbuf(void) +{ + if (test__start_subtest("ringbuf")) + ringbuf_subtest(); + if (test__start_subtest("ringbuf_map_key")) + ringbuf_map_key_subtest(); +} diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf_map_key.c b/tools/testing/selftests/bpf/progs/test_ringbuf_map_key.c new file mode 100644 index 000000000000..44f89c4d1f9e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_ringbuf_map_key.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */ + +#include +#include +#include "bpf_misc.h" + +char _license[] SEC("license") = "GPL"; + +struct sample { + int pid; + int seq; + long value; + char comm[16]; +}; + +struct { + __uint(type, BPF_MAP_TYPE_RINGBUF); + __uint(max_entries, 4096); +} ringbuf SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 1000); + __type(key, struct sample); + __type(value, int); +} hash_map SEC(".maps"); + +/* inputs */ +int pid = 0; + +/* inner state */ +long seq = 0; + +SEC("fentry/" SYS_PREFIX "sys_getpgid") +int test_ringbuf_mem_map_key(void *ctx) +{ + int cur_pid = bpf_get_current_pid_tgid() >> 32; + struct sample *sample, sample_copy; + int *lookup_val; + + if (cur_pid != pid) + return 0; + + sample = bpf_ringbuf_reserve(&ringbuf, sizeof(*sample), 0); + if (!sample) + return 0; + + sample->pid = pid; + bpf_get_current_comm(sample->comm, sizeof(sample->comm)); + sample->seq = ++seq; + sample->value = 42; + + /* test using 'sample' (PTR_TO_MEM | MEM_ALLOC) as map key arg + */ + lookup_val = (int *)bpf_map_lookup_elem(&hash_map, sample); + + /* workaround - memcpy is necessary so that verifier doesn't + * complain with: + * verifier internal error: more than one arg with ref_obj_id R3 + * when trying to do bpf_map_update_elem(&hash_map, sample, &sample->seq, BPF_ANY); + * + * Since bpf_map_lookup_elem above uses 'sample' as key, test using + * sample field as value below + */ + __builtin_memcpy(&sample_copy, sample, sizeof(struct sample)); + bpf_map_update_elem(&hash_map, &sample_copy, &sample->seq, BPF_ANY); + + bpf_ringbuf_submit(sample, 0); + return 0; +}