From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt1-f174.google.com (mail-qt1-f174.google.com [209.85.160.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DDB2638C for ; Fri, 8 Nov 2024 00:02:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731024149; cv=none; b=WPhtWWGH1QBJh3p1vskOSKln3JQV34lR7IvGj7CTQSitMf80PkQdVIMxiQpk0ra4C0TIDM61NbjHTp9dmBZb68nKeWQ7G2Dh6D2wMjay7vXEHoZcBfXwY6mDj9sx0Ym0AnZH9tfBdv0NWHIzq+WP6NPXWXVrMn4GLsjXw5s2P4Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731024149; c=relaxed/simple; bh=2MG9//RGDvIRpUHiW6s38hbiGw2pARbllLQUrUn/NSk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=CS5NloQOw8DnRgAaabzIInRVtPZQxOV7Ku2QGWmXlETWWWobWbhomMD1It8CYyJU78YnI3OkQfC1P5nUthmmsPJ75cITk4VOol2+TlaJGn4uMpqps5WFC8ZCZFJCJd8GKXNGwxahJdW4fmqo5PFkAgdkiVcIdh4eoC781n3UnTI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=bytedance.com; spf=pass smtp.mailfrom=bytedance.com; dkim=pass (2048-bit key) header.d=bytedance.com header.i=@bytedance.com header.b=c4zLCZ4F; arc=none smtp.client-ip=209.85.160.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=bytedance.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bytedance.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bytedance.com header.i=@bytedance.com header.b="c4zLCZ4F" Received: by mail-qt1-f174.google.com with SMTP id d75a77b69052e-4609d8874b1so10012711cf.3 for ; Thu, 07 Nov 2024 16:02:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1731024146; x=1731628946; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=9JHLVzplk+fSvzu6Q2t8SmBivUJYy0aGjGNOZjNnsGM=; b=c4zLCZ4FwW0uNan18rsJ30kpP5mkZtC88zvXy/gXmzNzuStwHag8yuJ/tc7CFmWBZc +xlPUjKsr4//N9y4fv3Misk121FLmp1T5VAZmWPsTMdEEdEkJlfhuGZ3Gha8DjFFKXSl WZ19tQWkerFc853LXsL10gBK52j20bCQEVQsrskbC8qwdFYVKCO6Ke1ZC2sVN2ZVQUOR jbgYfpUTceDtT9eVWY+gGtjuH6XCqDhBfZSa7u/njyT6/mmKIf1ywA2FSOJsb4PtxQxL 97P80DS7PcTfUo6boTWouOEgguV4PLbGik66JyWqY4eNCo4sWS6Et3tATb5wD8sMYB1x 6MLA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1731024146; x=1731628946; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=9JHLVzplk+fSvzu6Q2t8SmBivUJYy0aGjGNOZjNnsGM=; b=YUwfX26pTbDbVyxzKl/Zw+SH3/eIEsjjKagQ3IllZrR0QWqrrrEgRnmVUjI1QEA1au 4GlKGg8mMZSvMSBZTellaW+iHctR+heljjpaC6DirtICC4KAi6gcLbVqUz+UrG6DbGEd +q6EfZ6RjRh11EnVjx0KGVvWjC5NR0k+d1YDlU/5/EgJ2DcmWbKRNUWhJv1ZE1Ub+HjT 10VZxPcFThGdgt7Z2n9yimWZRb8AvclAA2GsqAIE+Z3bNs2aa62B+lcp1EcjWRie1atG qIzCginbrSXX/VLICVRs4kRTMOcxAS+mWV+8y0jus0rn+APnyI6CXhh4NQzhiYlGXAJZ fkYg== X-Forwarded-Encrypted: i=1; AJvYcCVGYVWt20VPUIufkuXItD9KizIur5ZdbmeKKF8PnIfPFQz06v65GO7h+OZb8p1j/LyDAFS1WG8=@vger.kernel.org X-Gm-Message-State: AOJu0YxyTkqpvbqc8URf/vqr1O6RnqhOXeT6tab5XWncbrZprK+6Dasj 9NlZ3DR/40Js4bfPqZO4CiG9ytX5Dz3twryP1RvHJrDyvGQB4yxdOom26OwrhLA= X-Google-Smtp-Source: AGHT+IE16mkFJKOM+UYMHKJ+xXAGCdoxHpEChKkBovuwExlvIWljbPf2YHP6Lfspclv8pfBc1LD7ew== X-Received: by 2002:ac8:594e:0:b0:461:1c54:5bcd with SMTP id d75a77b69052e-46309339b1emr11277051cf.13.1731024145805; Thu, 07 Nov 2024 16:02:25 -0800 (PST) Received: from [10.73.215.90] ([72.29.204.230]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-462ff4671f6sm13410171cf.39.2024.11.07.16.02.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 07 Nov 2024 16:02:24 -0800 (PST) Message-ID: <67a0fb14-f791-4499-8751-01bbbd1cafcb@bytedance.com> Date: Thu, 7 Nov 2024 16:02:19 -0800 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [External] [Patch bpf 2/2] selftests/bpf: Add a BPF selftest for bpf_skb_change_tail() To: Cong Wang , netdev@vger.kernel.org Cc: bpf@vger.kernel.org, Cong Wang , John Fastabend , Daniel Borkmann References: <20241107034141.250815-1-xiyou.wangcong@gmail.com> <20241107034141.250815-2-xiyou.wangcong@gmail.com> Content-Language: en-US From: Zijian Zhang In-Reply-To: <20241107034141.250815-2-xiyou.wangcong@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 11/6/24 7:41 PM, Cong Wang wrote: > From: Cong Wang > > As requested by Daniel, we need to add a selftest to cover > bpf_skb_change_tail() cases in skb_verdict. Here we test trimming, > growing and error cases, and validate its expected return values. > > Cc: John Fastabend > Cc: Daniel Borkmann > Cc: Zijian Zhang > Signed-off-by: Cong Wang > --- > .../selftests/bpf/prog_tests/sockmap_basic.c | 51 +++++++++++++++++++ > .../bpf/progs/test_sockmap_change_tail.c | 40 +++++++++++++++ > 2 files changed, 91 insertions(+) > create mode 100644 tools/testing/selftests/bpf/progs/test_sockmap_change_tail.c > > diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c > index 82bfb266741c..fe735fced836 100644 > --- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c > +++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c > @@ -12,6 +12,7 @@ > #include "test_sockmap_progs_query.skel.h" > #include "test_sockmap_pass_prog.skel.h" > #include "test_sockmap_drop_prog.skel.h" > +#include "test_sockmap_change_tail.skel.h" > #include "bpf_iter_sockmap.skel.h" > > #include "sockmap_helpers.h" > @@ -562,6 +563,54 @@ static void test_sockmap_skb_verdict_fionread(bool pass_prog) > test_sockmap_drop_prog__destroy(drop); > } > > +static void test_sockmap_skb_verdict_change_tail(void) > +{ > + struct test_sockmap_change_tail *skel; > + int err, map, verdict; > + int c1, p1, sent, recvd; > + int zero = 0; > + char b[3]; > + > + skel = test_sockmap_change_tail__open_and_load(); > + if (!ASSERT_OK_PTR(skel, "open_and_load")) > + return; > + verdict = bpf_program__fd(skel->progs.prog_skb_verdict); > + map = bpf_map__fd(skel->maps.sock_map_rx); > + > + err = bpf_prog_attach(verdict, map, BPF_SK_SKB_STREAM_VERDICT, 0); > + if (!ASSERT_OK(err, "bpf_prog_attach")) > + goto out; > + err = create_pair(AF_INET, SOCK_STREAM, &c1, &p1); > + if (!ASSERT_OK(err, "create_pair()")) > + goto out; > + err = bpf_map_update_elem(map, &zero, &c1, BPF_NOEXIST); > + if (!ASSERT_OK(err, "bpf_map_update_elem(c1)")) > + goto out_close; > + sent = xsend(p1, "Tr", 2, 0); > + ASSERT_EQ(sent, 2, "xsend(p1)"); > + recvd = recv(c1, b, 2, 0); > + ASSERT_EQ(recvd, 1, "recv(c1)"); > + ASSERT_EQ(skel->data->change_tail_ret, 0, "change_tail_ret"); > + > + sent = xsend(p1, "G", 1, 0); > + ASSERT_EQ(sent, 1, "xsend(p1)"); > + recvd = recv(c1, b, 2, 0); > + ASSERT_EQ(recvd, 2, "recv(c1)"); > + ASSERT_EQ(skel->data->change_tail_ret, 0, "change_tail_ret"); > + > + sent = xsend(p1, "E", 1, 0); > + ASSERT_EQ(sent, 1, "xsend(p1)"); > + recvd = recv(c1, b, 1, 0); > + ASSERT_EQ(recvd, 1, "recv(c1)"); > + ASSERT_EQ(skel->data->change_tail_ret, -EINVAL, "change_tail_ret"); > + > +out_close: > + close(c1); > + close(p1); > +out: > + test_sockmap_change_tail__destroy(skel); > +} > + > static void test_sockmap_skb_verdict_peek_helper(int map) > { > int err, c1, p1, zero = 0, sent, recvd, avail; > @@ -927,6 +976,8 @@ void test_sockmap_basic(void) > test_sockmap_skb_verdict_fionread(true); > if (test__start_subtest("sockmap skb_verdict fionread on drop")) > test_sockmap_skb_verdict_fionread(false); > + if (test__start_subtest("sockmap skb_verdict change tail")) > + test_sockmap_skb_verdict_change_tail(); > if (test__start_subtest("sockmap skb_verdict msg_f_peek")) > test_sockmap_skb_verdict_peek(); > if (test__start_subtest("sockmap skb_verdict msg_f_peek with link")) > diff --git a/tools/testing/selftests/bpf/progs/test_sockmap_change_tail.c b/tools/testing/selftests/bpf/progs/test_sockmap_change_tail.c > new file mode 100644 > index 000000000000..2796dd8545eb > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/test_sockmap_change_tail.c > @@ -0,0 +1,40 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2024 ByteDance */ > +#include > +#include > + > +struct { > + __uint(type, BPF_MAP_TYPE_SOCKMAP); > + __uint(max_entries, 1); > + __type(key, int); > + __type(value, int); > +} sock_map_rx SEC(".maps"); > + > +long change_tail_ret = 1; > + > +SEC("sk_skb") > +int prog_skb_verdict(struct __sk_buff *skb) > +{ > + char *data, *data_end; > + > + bpf_skb_pull_data(skb, 1); > + data = (char *)(unsigned long)skb->data; > + data_end = (char *)(unsigned long)skb->data_end; > + > + if (data + 1 > data_end) > + return SK_PASS; > + > + if (data[0] == 'T') { /* Trim the packet */ > + change_tail_ret = bpf_skb_change_tail(skb, skb->len - 1, 0); > + return SK_PASS; > + } else if (data[0] == 'G') { /* Grow the packet */ > + change_tail_ret = bpf_skb_change_tail(skb, skb->len + 1, 0); > + return SK_PASS; > + } else if (data[0] == 'E') { /* Error */ > + change_tail_ret = bpf_skb_change_tail(skb, 65535, 0); > + return SK_PASS; > + } > + return SK_PASS; > +} > + > +char _license[] SEC("license") = "GPL"; LGTM! I think it will be better if the test could also cover the case you indicated in the first patch, where skb_transport_offset is a negative value. Thanks, Zijian