From patchwork Tue Aug 10 09:28:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Iwashima, Kuniyuki" X-Patchwork-Id: 12428439 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 X-Spam-Level: X-Spam-Status: No, score=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0FFB8C4338F for ; Tue, 10 Aug 2021 09:28:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D65F460EE9 for ; Tue, 10 Aug 2021 09:28:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239039AbhHJJ3T (ORCPT ); Tue, 10 Aug 2021 05:29:19 -0400 Received: from smtp-fw-2101.amazon.com ([72.21.196.25]:31799 "EHLO smtp-fw-2101.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239044AbhHJJ3P (ORCPT ); Tue, 10 Aug 2021 05:29:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.co.jp; i=@amazon.co.jp; q=dns/txt; s=amazon201209; t=1628587733; x=1660123733; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=pVTCG2sZF4HudW7SXxCkqAlOLFNBz4kCZYdFOaun0t8=; b=KJt/bXfX0cQuSszffKHvvALdLH6FvgbLgu+MksSvsqRm8xPNQ44BrEmT WwdEvndbseyrzbn3cIUMylf/s/CzQ2rrpQ0kwB8rLJIl5XWeoeLGo+U3Q kAZa+nz7Qg42wB0GxMqG190KAKoruPXcXVkB7DnqQej8dPgIPs8/Xkydr c=; X-IronPort-AV: E=Sophos;i="5.84,310,1620691200"; d="scan'208";a="128371280" Received: from iad12-co-svc-p1-lb1-vlan2.amazon.com (HELO email-inbound-relay-1d-37fd6b3d.us-east-1.amazon.com) ([10.43.8.2]) by smtp-border-fw-2101.iad2.amazon.com with ESMTP; 10 Aug 2021 09:28:52 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan3.iad.amazon.com [10.40.159.166]) by email-inbound-relay-1d-37fd6b3d.us-east-1.amazon.com (Postfix) with ESMTPS id AF59D280168; Tue, 10 Aug 2021 09:28:49 +0000 (UTC) Received: from EX13D04ANC001.ant.amazon.com (10.43.157.89) by EX13MTAUWB001.ant.amazon.com (10.43.161.249) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 10 Aug 2021 09:28:48 +0000 Received: from 88665a182662.ant.amazon.com (10.43.160.189) by EX13D04ANC001.ant.amazon.com (10.43.157.89) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 10 Aug 2021 09:28:37 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , "Song Liu" , Yonghong Song , John Fastabend , KP Singh CC: Benjamin Herrenschmidt , Kuniyuki Iwashima , Kuniyuki Iwashima , , Subject: [PATCH v4 bpf-next 1/3] bpf: af_unix: Implement BPF iterator for UNIX domain socket. Date: Tue, 10 Aug 2021 18:28:05 +0900 Message-ID: <20210810092807.13190-2-kuniyu@amazon.co.jp> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210810092807.13190-1-kuniyu@amazon.co.jp> References: <20210810092807.13190-1-kuniyu@amazon.co.jp> MIME-Version: 1.0 X-Originating-IP: [10.43.160.189] X-ClientProxiedBy: EX13D08UWC001.ant.amazon.com (10.43.162.110) To EX13D04ANC001.ant.amazon.com (10.43.157.89) Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net This patch implements the BPF iterator for the UNIX domain socket. Currently, the batch optimisation introduced for the TCP iterator in the commit 04c7820b776f ("bpf: tcp: Bpf iter batching and lock_sock") is not used for the UNIX domain socket. It will require replacing the big lock for the hash table with small locks for each hash list not to block other processes. Signed-off-by: Kuniyuki Iwashima Acked-by: Yonghong Song --- include/linux/btf_ids.h | 3 +- net/unix/af_unix.c | 93 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 95 insertions(+), 1 deletion(-) diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index 57890b357f85..bed4b9964581 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -172,7 +172,8 @@ extern struct btf_id_set name; BTF_SOCK_TYPE(BTF_SOCK_TYPE_TCP_TW, tcp_timewait_sock) \ BTF_SOCK_TYPE(BTF_SOCK_TYPE_TCP6, tcp6_sock) \ BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP, udp_sock) \ - BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP6, udp6_sock) + BTF_SOCK_TYPE(BTF_SOCK_TYPE_UDP6, udp6_sock) \ + BTF_SOCK_TYPE(BTF_SOCK_TYPE_UNIX, unix_sock) enum { #define BTF_SOCK_TYPE(name, str) name, diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 256c4e31132e..15e1f1bc22a8 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -113,6 +113,7 @@ #include #include #include +#include #include "scm.h" @@ -2982,6 +2983,64 @@ static const struct seq_operations unix_seq_ops = { .stop = unix_seq_stop, .show = unix_seq_show, }; + +#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) +struct bpf_iter__unix { + __bpf_md_ptr(struct bpf_iter_meta *, meta); + __bpf_md_ptr(struct unix_sock *, unix_sk); + uid_t uid __aligned(8); +}; + +static int unix_prog_seq_show(struct bpf_prog *prog, struct bpf_iter_meta *meta, + struct unix_sock *unix_sk, uid_t uid) +{ + struct bpf_iter__unix ctx; + + meta->seq_num--; /* skip SEQ_START_TOKEN */ + ctx.meta = meta; + ctx.unix_sk = unix_sk; + ctx.uid = uid; + return bpf_iter_run_prog(prog, &ctx); +} + +static int bpf_iter_unix_seq_show(struct seq_file *seq, void *v) +{ + struct bpf_iter_meta meta; + struct bpf_prog *prog; + struct sock *sk = v; + uid_t uid; + + if (v == SEQ_START_TOKEN) + return 0; + + uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)); + meta.seq = seq; + prog = bpf_iter_get_info(&meta, false); + return unix_prog_seq_show(prog, &meta, v, uid); +} + +static void bpf_iter_unix_seq_stop(struct seq_file *seq, void *v) +{ + struct bpf_iter_meta meta; + struct bpf_prog *prog; + + if (!v) { + meta.seq = seq; + prog = bpf_iter_get_info(&meta, true); + if (prog) + (void)unix_prog_seq_show(prog, &meta, v, 0); + } + + unix_seq_stop(seq, v); +} + +static const struct seq_operations bpf_iter_unix_seq_ops = { + .start = unix_seq_start, + .next = unix_seq_next, + .stop = bpf_iter_unix_seq_stop, + .show = bpf_iter_unix_seq_show, +}; +#endif #endif static const struct net_proto_family unix_family_ops = { @@ -3022,6 +3081,35 @@ static struct pernet_operations unix_net_ops = { .exit = unix_net_exit, }; +#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) +DEFINE_BPF_ITER_FUNC(unix, struct bpf_iter_meta *meta, + struct unix_sock *unix_sk, uid_t uid) + +static const struct bpf_iter_seq_info unix_seq_info = { + .seq_ops = &bpf_iter_unix_seq_ops, + .init_seq_private = bpf_iter_init_seq_net, + .fini_seq_private = bpf_iter_fini_seq_net, + .seq_priv_size = sizeof(struct seq_net_private), +}; + +static struct bpf_iter_reg unix_reg_info = { + .target = "unix", + .ctx_arg_info_size = 1, + .ctx_arg_info = { + { offsetof(struct bpf_iter__unix, unix_sk), + PTR_TO_BTF_ID_OR_NULL }, + }, + .seq_info = &unix_seq_info, +}; + +static void __init bpf_iter_register(void) +{ + unix_reg_info.ctx_arg_info[0].btf_id = btf_sock_ids[BTF_SOCK_TYPE_UNIX]; + if (bpf_iter_reg_target(&unix_reg_info)) + pr_warn("Warning: could not register bpf iterator unix\n"); +} +#endif + static int __init af_unix_init(void) { int rc = -1; @@ -3037,6 +3125,11 @@ static int __init af_unix_init(void) sock_register(&unix_family_ops); register_pernet_subsys(&unix_net_ops); unix_bpf_build_proto(); + +#if IS_BUILTIN(CONFIG_UNIX) && defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) + bpf_iter_register(); +#endif + out: return rc; } From patchwork Tue Aug 10 09:28:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Iwashima, Kuniyuki" X-Patchwork-Id: 12428441 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 X-Spam-Level: X-Spam-Status: No, score=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E30DC4338F for ; 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X-IronPort-AV: E=Sophos;i="5.84,310,1620691200"; d="scan'208";a="132824593" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO email-inbound-relay-1d-e69428c4.us-east-1.amazon.com) ([10.43.8.6]) by smtp-border-fw-6001.iad6.amazon.com with ESMTP; 10 Aug 2021 09:29:02 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan3.iad.amazon.com [10.40.159.166]) by email-inbound-relay-1d-e69428c4.us-east-1.amazon.com (Postfix) with ESMTPS id 3FD8DC0C4D; Tue, 10 Aug 2021 09:28:57 +0000 (UTC) Received: from EX13D04ANC001.ant.amazon.com (10.43.157.89) by EX13MTAUWB001.ant.amazon.com (10.43.161.249) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 10 Aug 2021 09:28:57 +0000 Received: from 88665a182662.ant.amazon.com (10.43.160.189) by EX13D04ANC001.ant.amazon.com (10.43.157.89) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 10 Aug 2021 09:28:52 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , "Song Liu" , Yonghong Song , John Fastabend , KP Singh CC: Benjamin Herrenschmidt , Kuniyuki Iwashima , Kuniyuki Iwashima , , Subject: [PATCH v4 bpf-next 2/3] bpf: Support "%c" in bpf_bprintf_prepare(). Date: Tue, 10 Aug 2021 18:28:06 +0900 Message-ID: <20210810092807.13190-3-kuniyu@amazon.co.jp> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210810092807.13190-1-kuniyu@amazon.co.jp> References: <20210810092807.13190-1-kuniyu@amazon.co.jp> MIME-Version: 1.0 X-Originating-IP: [10.43.160.189] X-ClientProxiedBy: EX13D08UWC001.ant.amazon.com (10.43.162.110) To EX13D04ANC001.ant.amazon.com (10.43.157.89) Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net /proc/net/unix uses "%c" to print a single-byte character to escape '\0' in the name of the abstract UNIX domain socket. The following selftest uses it, so this patch adds support for "%c". Note that it does not support wide character ("%lc" and "%llc") for simplicity. Signed-off-by: Kuniyuki Iwashima Acked-by: Yonghong Song --- kernel/bpf/helpers.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 15746f779fe1..6d3aaf94e9ac 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -907,6 +907,20 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args, tmp_buf += err; num_spec++; + continue; + } else if (fmt[i] == 'c') { + if (!tmp_buf) + goto nocopy_fmt; + + if (tmp_buf_end == tmp_buf) { + err = -ENOSPC; + goto out; + } + + *tmp_buf = raw_args[num_spec]; + tmp_buf++; + num_spec++; + continue; } From patchwork Tue Aug 10 09:28:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Iwashima, Kuniyuki" X-Patchwork-Id: 12428443 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 X-Spam-Level: X-Spam-Status: No, score=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CAB7C4338F for ; Tue, 10 Aug 2021 09:29:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D8816101E for ; Tue, 10 Aug 2021 09:29:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239060AbhHJJ3k (ORCPT ); Tue, 10 Aug 2021 05:29:40 -0400 Received: from smtp-fw-6002.amazon.com ([52.95.49.90]:51880 "EHLO smtp-fw-6002.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239040AbhHJJ3j (ORCPT ); Tue, 10 Aug 2021 05:29:39 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.co.jp; i=@amazon.co.jp; q=dns/txt; s=amazon201209; t=1628587758; x=1660123758; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=58FirQic48gQBVWPcqbVM+Kk3BB+dXmREPIW7gMAn1Y=; b=DkcAuzuF8tBAzsdI0cud5cbknDkAKH5rK7NyyRhYI1o6Uz5a+YnyU3Sx NjuoCtNNje+paNtvJBJZKK6GIZpVTY9bVAkB+L8q+ZtCFhhl44489paPs KDQe2Y/eB8lxZR0i8XhO1pRDhgqJwO0eDHo5iHfbKkAwKm8gNxxs8Sr8Z Q=; X-IronPort-AV: E=Sophos;i="5.84,310,1620691200"; d="scan'208";a="131372522" Received: from iad12-co-svc-p1-lb1-vlan2.amazon.com (HELO email-inbound-relay-1d-e69428c4.us-east-1.amazon.com) ([10.43.8.2]) by smtp-border-fw-6002.iad6.amazon.com with ESMTP; 10 Aug 2021 09:29:18 +0000 Received: from EX13MTAUWB001.ant.amazon.com (iad55-ws-svc-p15-lb9-vlan3.iad.amazon.com [10.40.159.166]) by email-inbound-relay-1d-e69428c4.us-east-1.amazon.com (Postfix) with ESMTPS id BC5C5C2AC1; Tue, 10 Aug 2021 09:29:14 +0000 (UTC) Received: from EX13D04ANC001.ant.amazon.com (10.43.157.89) by EX13MTAUWB001.ant.amazon.com (10.43.161.249) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 10 Aug 2021 09:29:13 +0000 Received: from 88665a182662.ant.amazon.com (10.43.160.189) by EX13D04ANC001.ant.amazon.com (10.43.157.89) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Tue, 10 Aug 2021 09:29:08 +0000 From: Kuniyuki Iwashima To: "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , "Song Liu" , Yonghong Song , John Fastabend , KP Singh CC: Benjamin Herrenschmidt , Kuniyuki Iwashima , Kuniyuki Iwashima , , Subject: [PATCH v4 bpf-next 3/3] selftest/bpf: Implement sample UNIX domain socket iterator program. Date: Tue, 10 Aug 2021 18:28:07 +0900 Message-ID: <20210810092807.13190-4-kuniyu@amazon.co.jp> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210810092807.13190-1-kuniyu@amazon.co.jp> References: <20210810092807.13190-1-kuniyu@amazon.co.jp> MIME-Version: 1.0 X-Originating-IP: [10.43.160.189] X-ClientProxiedBy: EX13D08UWC001.ant.amazon.com (10.43.162.110) To EX13D04ANC001.ant.amazon.com (10.43.157.89) Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net The iterator can output the same result compared to /proc/net/unix. # cat /sys/fs/bpf/unix Num RefCount Protocol Flags Type St Inode Path ffff9ab7122db000: 00000002 00000000 00010000 0001 01 10623 private/defer ffff9fca0023d000: 00000002 00000000 00000000 0001 01 11058 @Hello@World@ # cat /proc/net/unix Num RefCount Protocol Flags Type St Inode Path ffff9ab7122db000: 00000002 00000000 00010000 0001 01 10623 private/defer ffff9fca0023d000: 00000002 00000000 00000000 0001 01 11058 @Hello@World@ Note that this prog requires the patch ([0]) for LLVM code gen. Thanks to Yonghong Song for analysing and fixing. [0] https://reviews.llvm.org/D107483 Signed-off-by: Kuniyuki Iwashima Acked-by: Yonghong Song --- tools/testing/selftests/bpf/README.rst | 38 +++++++++ .../selftests/bpf/prog_tests/bpf_iter.c | 16 ++++ tools/testing/selftests/bpf/progs/bpf_iter.h | 8 ++ .../selftests/bpf/progs/bpf_iter_unix.c | 77 +++++++++++++++++++ .../selftests/bpf/progs/bpf_tracing_net.h | 4 + 5 files changed, 143 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/bpf_iter_unix.c diff --git a/tools/testing/selftests/bpf/README.rst b/tools/testing/selftests/bpf/README.rst index 9b17f2867488..314a63b69399 100644 --- a/tools/testing/selftests/bpf/README.rst +++ b/tools/testing/selftests/bpf/README.rst @@ -228,3 +228,41 @@ To fix this issue, user newer libbpf. .. Links .. _clang reloc patch: https://reviews.llvm.org/D102712 .. _kernel llvm reloc: /Documentation/bpf/llvm_reloc.rst + +bpf_iter_unix.o test failure and LLVM optimisation +================================================== + +The ``bpf_iter/unix`` subtest requires `the fix`__ to prevent the LLVM compiler +from transforming the loop exit condition. + +Without the fix, the compiler generates the following code: + +.. code-block:: c + + ; for (i = 1; i < len; i++) + 110: 07 09 00 00 01 00 00 00 r9 += 1 + 111: 5d 98 09 00 00 00 00 00 if r8 != r9 goto +9 + +The loop exit condition, where the upper bound is not a constant, is +changed from ``<`` to ``!=``. Thus, the verifier always evaluates it as true, +misleading to an infinite loop. + +.. code-block:: c + + The sequence of 8193 jumps is too complex. + processed 196506 insns (limit 1000000) max_states_per_insn 4 total_states 1830 peak_states 1830 mark_read 3 + +The fix prevents the optimisation by estimating its cost higher in such a +case: + +.. code-block:: c + + ; for (i = 1; i < len; i++) + 110: 07 09 00 00 01 00 00 00 r9 += 1 + 111: ad 89 09 00 00 00 00 00 if r9 < r8 goto +9 + +The patch is available in LLVM 14 trunk and has been `backported`__ to the LLVM +13.x release branch. + +__ https://reviews.llvm.org/D107483 +__ https://bugs.llvm.org/show_bug.cgi?id=51363 diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 1f1aade56504..77ac24b191d4 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -13,6 +13,7 @@ #include "bpf_iter_tcp6.skel.h" #include "bpf_iter_udp4.skel.h" #include "bpf_iter_udp6.skel.h" +#include "bpf_iter_unix.skel.h" #include "bpf_iter_test_kern1.skel.h" #include "bpf_iter_test_kern2.skel.h" #include "bpf_iter_test_kern3.skel.h" @@ -313,6 +314,19 @@ static void test_udp6(void) bpf_iter_udp6__destroy(skel); } +static void test_unix(void) +{ + struct bpf_iter_unix *skel; + + skel = bpf_iter_unix__open_and_load(); + if (!ASSERT_OK_PTR(skel, "bpf_iter_unix__open_and_load")) + return; + + do_dummy_read(skel->progs.dump_unix); + + bpf_iter_unix__destroy(skel); +} + /* The expected string is less than 16 bytes */ static int do_read_with_fd(int iter_fd, const char *expected, bool read_one_char) @@ -1255,6 +1269,8 @@ void test_bpf_iter(void) test_udp4(); if (test__start_subtest("udp6")) test_udp6(); + if (test__start_subtest("unix")) + test_unix(); if (test__start_subtest("anon")) test_anon_iter(false); if (test__start_subtest("anon-read-one-char")) diff --git a/tools/testing/selftests/bpf/progs/bpf_iter.h b/tools/testing/selftests/bpf/progs/bpf_iter.h index 3d83b185c4bc..8cfaeba1ddbf 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter.h +++ b/tools/testing/selftests/bpf/progs/bpf_iter.h @@ -12,6 +12,7 @@ #define tcp6_sock tcp6_sock___not_used #define bpf_iter__udp bpf_iter__udp___not_used #define udp6_sock udp6_sock___not_used +#define bpf_iter__unix bpf_iter__unix___not_used #define bpf_iter__bpf_map_elem bpf_iter__bpf_map_elem___not_used #define bpf_iter__bpf_sk_storage_map bpf_iter__bpf_sk_storage_map___not_used #define bpf_iter__sockmap bpf_iter__sockmap___not_used @@ -32,6 +33,7 @@ #undef tcp6_sock #undef bpf_iter__udp #undef udp6_sock +#undef bpf_iter__unix #undef bpf_iter__bpf_map_elem #undef bpf_iter__bpf_sk_storage_map #undef bpf_iter__sockmap @@ -103,6 +105,12 @@ struct udp6_sock { struct ipv6_pinfo inet6; } __attribute__((preserve_access_index)); +struct bpf_iter__unix { + struct bpf_iter_meta *meta; + struct unix_sock *unix_sk; + uid_t uid; +} __attribute__((preserve_access_index)); + struct bpf_iter__bpf_map_elem { struct bpf_iter_meta *meta; struct bpf_map *map; diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_unix.c b/tools/testing/selftests/bpf/progs/bpf_iter_unix.c new file mode 100644 index 000000000000..06e417ff718b --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_unix.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright Amazon.com Inc. or its affiliates. */ +#include "bpf_iter.h" +#include "bpf_tracing_net.h" +#include +#include + +char _license[] SEC("license") = "GPL"; + +static long sock_i_ino(const struct sock *sk) +{ + const struct socket *sk_socket = sk->sk_socket; + const struct inode *inode; + unsigned long ino; + + if (!sk_socket) + return 0; + + inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode; + bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino); + return ino; +} + +SEC("iter/unix") +int dump_unix(struct bpf_iter__unix *ctx) +{ + struct unix_sock *unix_sk = ctx->unix_sk; + struct sock *sk = (struct sock *)unix_sk; + struct seq_file *seq; + __u32 seq_num; + + if (!unix_sk) + return 0; + + seq = ctx->meta->seq; + seq_num = ctx->meta->seq_num; + if (seq_num == 0) + BPF_SEQ_PRINTF(seq, "Num RefCount Protocol Flags Type St Inode Path\n"); + + BPF_SEQ_PRINTF(seq, "%pK: %08X %08X %08X %04X %02X %5lu", + unix_sk, + sk->sk_refcnt.refs.counter, + 0, + sk->sk_state == TCP_LISTEN ? __SO_ACCEPTCON : 0, + sk->sk_type, + sk->sk_socket ? + (sk->sk_state == TCP_ESTABLISHED ? SS_CONNECTED : SS_UNCONNECTED) : + (sk->sk_state == TCP_ESTABLISHED ? SS_CONNECTING : SS_DISCONNECTING), + sock_i_ino(sk)); + + if (unix_sk->addr) { + if (!UNIX_ABSTRACT(unix_sk)) { + BPF_SEQ_PRINTF(seq, " %s", unix_sk->addr->name->sun_path); + } else { + /* The name of the abstract UNIX domain socket starts + * with '\0' and can contain '\0'. The null bytes + * should be escaped as done in unix_seq_show(). + */ + int i, len; + + len = unix_sk->addr->len - sizeof(short); + + BPF_SEQ_PRINTF(seq, " @"); + + /* unix_mkname() tests this upper bound. */ + if (len < sizeof(struct sockaddr_un)) + for (i = 1; i < len; i++) + BPF_SEQ_PRINTF(seq, "%c", + unix_sk->addr->name->sun_path[i] ?: + '@'); + } + } + + BPF_SEQ_PRINTF(seq, "\n"); + + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/bpf_tracing_net.h b/tools/testing/selftests/bpf/progs/bpf_tracing_net.h index 3af0998a0623..eef5646ddb19 100644 --- a/tools/testing/selftests/bpf/progs/bpf_tracing_net.h +++ b/tools/testing/selftests/bpf/progs/bpf_tracing_net.h @@ -5,6 +5,10 @@ #define AF_INET 2 #define AF_INET6 10 +#define __SO_ACCEPTCON (1 << 16) +#define UNIX_HASH_SIZE 256 +#define UNIX_ABSTRACT(unix_sk) (unix_sk->addr->hash < UNIX_HASH_SIZE) + #define SOL_TCP 6 #define TCP_CONGESTION 13 #define TCP_CA_NAME_MAX 16