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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A05C4C433F5 for ; Mon, 25 Oct 2021 11:46:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8160461050 for ; Mon, 25 Oct 2021 11:46:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232659AbhJYLsi (ORCPT ); Mon, 25 Oct 2021 07:48:38 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:13978 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230216AbhJYLsh (ORCPT ); Mon, 25 Oct 2021 07:48:37 -0400 Received: from dggemv711-chm.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4HdCm35sMFzZcLN; Mon, 25 Oct 2021 19:44:19 +0800 (CST) Received: from dggpeml500011.china.huawei.com (7.185.36.84) by dggemv711-chm.china.huawei.com (10.1.198.66) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Mon, 25 Oct 2021 19:46:13 +0800 Received: from localhost.localdomain (10.175.101.6) by dggpeml500011.china.huawei.com (7.185.36.84) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Mon, 25 Oct 2021 19:46:12 +0800 From: Di Zhu To: , , , , , , , , , CC: , , Subject: [PATCH v3] bpf: support BPF_PROG_QUERY for progs attached to sockmap Date: Mon, 25 Oct 2021 19:36:08 +0800 Message-ID: <20211025113608.1511504-1-zhudi2@huawei.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpeml500011.china.huawei.com (7.185.36.84) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Right now there is no way to query whether BPF programs are attached to a sockmap or not. we can use the standard interface in libbpf to query, such as: bpf_prog_query(mapFd, BPF_SK_SKB_STREAM_PARSER, 0, NULL, ...); the mapFd is the fd of sockmap. Signed-off-by: Di Zhu --- /* v2 */ - John Fastabend - add selftest code /* v3 */ - avoid sleeping caused by copy_to_user() in rcu critical zone --- include/linux/bpf.h | 9 ++ kernel/bpf/syscall.c | 5 ++ net/core/sock_map.c | 88 +++++++++++++++++-- .../selftests/bpf/prog_tests/sockmap_basic.c | 85 ++++++++++++++++++ .../bpf/progs/test_sockmap_progs_query.c | 25 ++++++ 5 files changed, 205 insertions(+), 7 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/test_sockmap_progs_query.c diff --git a/include/linux/bpf.h b/include/linux/bpf.h index d604c8251d88..db7d0e5115b7 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1961,6 +1961,9 @@ int bpf_prog_test_run_syscall(struct bpf_prog *prog, int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog); int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype); int sock_map_update_elem_sys(struct bpf_map *map, void *key, void *value, u64 flags); +int sockmap_bpf_prog_query(const union bpf_attr *attr, + union bpf_attr __user *uattr); + void sock_map_unhash(struct sock *sk); void sock_map_close(struct sock *sk, long timeout); #else @@ -2014,6 +2017,12 @@ static inline int sock_map_update_elem_sys(struct bpf_map *map, void *key, void { return -EOPNOTSUPP; } + +static inline int sockmap_bpf_prog_query(const union bpf_attr *attr, + union bpf_attr __user *uattr) +{ + return -EINVAL; +} #endif /* CONFIG_BPF_SYSCALL */ #endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */ diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 4e50c0bfdb7d..17faeff8f85f 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -3275,6 +3275,11 @@ static int bpf_prog_query(const union bpf_attr *attr, case BPF_FLOW_DISSECTOR: case BPF_SK_LOOKUP: return netns_bpf_prog_query(attr, uattr); + case BPF_SK_SKB_STREAM_PARSER: + case BPF_SK_SKB_STREAM_VERDICT: + case BPF_SK_MSG_VERDICT: + case BPF_SK_SKB_VERDICT: + return sockmap_bpf_prog_query(attr, uattr); default: return -EINVAL; } diff --git a/net/core/sock_map.c b/net/core/sock_map.c index e252b8ec2b85..ca65ed0004d3 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -1412,38 +1412,50 @@ static struct sk_psock_progs *sock_map_progs(struct bpf_map *map) return NULL; } -static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog, - struct bpf_prog *old, u32 which) +static int sock_map_prog_lookup(struct bpf_map *map, struct bpf_prog **pprog[], + u32 which) { struct sk_psock_progs *progs = sock_map_progs(map); - struct bpf_prog **pprog; if (!progs) return -EOPNOTSUPP; switch (which) { case BPF_SK_MSG_VERDICT: - pprog = &progs->msg_parser; + *pprog = &progs->msg_parser; break; #if IS_ENABLED(CONFIG_BPF_STREAM_PARSER) case BPF_SK_SKB_STREAM_PARSER: - pprog = &progs->stream_parser; + *pprog = &progs->stream_parser; break; #endif case BPF_SK_SKB_STREAM_VERDICT: if (progs->skb_verdict) return -EBUSY; - pprog = &progs->stream_verdict; + *pprog = &progs->stream_verdict; break; case BPF_SK_SKB_VERDICT: if (progs->stream_verdict) return -EBUSY; - pprog = &progs->skb_verdict; + *pprog = &progs->skb_verdict; break; default: return -EOPNOTSUPP; } + return 0; +} + +static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog, + struct bpf_prog *old, u32 which) +{ + struct bpf_prog **pprog; + int ret; + + ret = sock_map_prog_lookup(map, &pprog, which); + if (ret) + return ret; + if (old) return psock_replace_prog(pprog, prog, old); @@ -1451,6 +1463,68 @@ static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog, return 0; } +int sockmap_bpf_prog_query(const union bpf_attr *attr, + union bpf_attr __user *uattr) +{ + __u32 __user *prog_ids = u64_to_user_ptr(attr->query.prog_ids); + u32 prog_cnt = 0, flags = 0; + u32 ufd = attr->target_fd; + struct bpf_prog **pprog; + struct bpf_prog *prog; + struct bpf_map *map; + struct fd f; + int ret; + u32 id = 0; + + if (attr->query.query_flags) + return -EINVAL; + + f = fdget(ufd); + map = __bpf_map_get(f); + if (IS_ERR(map)) + return PTR_ERR(map); + + rcu_read_lock(); + + ret = sock_map_prog_lookup(map, &pprog, attr->query.attach_type); + if (ret) + goto end; + + prog = *pprog; + prog_cnt = (!prog) ? 0 : 1; + + if (!attr->query.prog_cnt || !prog_ids || !prog_cnt) + goto end; + + prog = bpf_prog_inc_not_zero(prog); + if (IS_ERR(prog)) { + ret = PTR_ERR(prog); + goto end; + } + id = prog->aux->id; + bpf_prog_put(prog); + +end: + rcu_read_unlock(); + + if (copy_to_user(&uattr->query.attach_flags, &flags, sizeof(flags))) { + ret = -EFAULT; + goto err; + } + if (id != 0 && copy_to_user(prog_ids, &id, sizeof(u32))) { + ret = -EFAULT; + goto err; + } + if (copy_to_user(&uattr->query.prog_cnt, &prog_cnt, sizeof(prog_cnt))) { + ret = -EFAULT; + goto err; + } + +err: + fdput(f); + return ret; +} + static void sock_map_unlink(struct sock *sk, struct sk_psock_link *link) { switch (link->map->map_type) { diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c index 1352ec104149..23fd89661ef5 100644 --- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c @@ -8,6 +8,7 @@ #include "test_sockmap_update.skel.h" #include "test_sockmap_invalid_update.skel.h" #include "test_sockmap_skb_verdict_attach.skel.h" +#include "test_sockmap_progs_query.skel.h" #include "bpf_iter_sockmap.skel.h" #define TCP_REPAIR 19 /* TCP sock is under repair right now */ @@ -315,6 +316,84 @@ static void test_sockmap_skb_verdict_attach(enum bpf_attach_type first, test_sockmap_skb_verdict_attach__destroy(skel); } +static __u32 query_prog_id(int prog) +{ + struct bpf_prog_info info = {}; + __u32 info_len = sizeof(info); + int err; + + err = bpf_obj_get_info_by_fd(prog, &info, &info_len); + if (CHECK_FAIL(err || info_len != sizeof(info))) { + perror("bpf_obj_get_info_by_fd"); + return 0; + } + + return info.id; +} + +static void test_sockmap_progs_query(enum bpf_attach_type attach_type) +{ + struct test_sockmap_progs_query *skel; + int err, map, verdict, duration = 0; + __u32 attach_flags = 0; + __u32 prog_ids[3] = {}; + __u32 prog_cnt = 3; + + skel = test_sockmap_progs_query__open_and_load(); + if (CHECK_FAIL(!skel)) { + perror("test_sockmap_progs_query__open_and_load"); + return; + } + + map = bpf_map__fd(skel->maps.sock_map); + + if (attach_type == BPF_SK_MSG_VERDICT) + verdict = bpf_program__fd(skel->progs.prog_skmsg_verdict); + else + verdict = bpf_program__fd(skel->progs.prog_skb_verdict); + + err = bpf_prog_query(map, attach_type, 0 /* query flags */, + &attach_flags, prog_ids, &prog_cnt); + if (CHECK(err, "bpf_prog_query", "failed\n")) + goto out; + + if (CHECK(attach_flags != 0, "bpf_prog_query", + "wrong attach_flags on query: %u", attach_flags)) + goto out; + + if (CHECK(prog_cnt != 0, "bpf_prog_query", + "wrong program count on query: %u", prog_cnt)) + goto out; + + err = bpf_prog_attach(verdict, map, attach_type, 0); + if (CHECK(err, "bpf_prog_attach", "failed\n")) + goto out; + + prog_cnt = 1; + err = bpf_prog_query(map, attach_type, 0 /* query flags */, + &attach_flags, prog_ids, &prog_cnt); + if (CHECK(err, "bpf_prog_query", "failed\n")) + goto detach; + + if (CHECK(attach_flags != 0, "bpf_prog_query", + "wrong attach_flags on query: %u", attach_flags)) + goto detach; + + if (CHECK(prog_cnt != 1, "bpf_prog_query", + "wrong program count on query: %u", prog_cnt)) + goto detach; + + if (CHECK(prog_ids[0] != query_prog_id(verdict), "bpf_prog_query", + "wrong prog id on query: %u", prog_ids[0])) + goto detach; + +detach: + bpf_prog_detach2(verdict, map, attach_type); +out: + test_sockmap_progs_query__destroy(skel); + +} + void test_sockmap_basic(void) { if (test__start_subtest("sockmap create_update_free")) @@ -341,4 +420,10 @@ void test_sockmap_basic(void) test_sockmap_skb_verdict_attach(BPF_SK_SKB_STREAM_VERDICT, BPF_SK_SKB_VERDICT); } + if (test__start_subtest("sockmap progs query")) { + test_sockmap_progs_query(BPF_SK_MSG_VERDICT); + test_sockmap_progs_query(BPF_SK_SKB_STREAM_PARSER); + test_sockmap_progs_query(BPF_SK_SKB_STREAM_VERDICT); + test_sockmap_progs_query(BPF_SK_SKB_VERDICT); + } } diff --git a/tools/testing/selftests/bpf/progs/test_sockmap_progs_query.c b/tools/testing/selftests/bpf/progs/test_sockmap_progs_query.c new file mode 100644 index 000000000000..ec0da297cf80 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_sockmap_progs_query.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "vmlinux.h" +#include + +struct { + __uint(type, BPF_MAP_TYPE_SOCKMAP); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u64); +} sock_map SEC(".maps"); + +SEC("sk_skb") +int prog_skb_verdict(struct __sk_buff *skb) +{ + return SK_PASS; +} + +SEC("sk_msg") +int prog_skmsg_verdict(struct sk_msg_md *msg) +{ + return SK_PASS; +} + +char _license[] SEC("license") = "GPL"; + -- 2.27.0