From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-183.mta0.migadu.com (out-183.mta0.migadu.com [91.218.175.183]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5A7253B9DAB for ; Thu, 14 May 2026 05:10:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.183 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778735451; cv=none; b=U8V9dYk3lrpWzM0Ytu8S4LZTMAWMC0/EYCl2fwrdFjSZYZHwfcnSL/+SRtTqGdQ7YAY6c3sSBiNis0LwH+ybt1XYKuHXoSYVMC8pq4mFGb5EPGJfZZyDdmZsD1hhjed6TQhXgLI3AvgN8ES6yeZwUtlgnI1gIGZP6ScxQJCD7+Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778735451; c=relaxed/simple; bh=q+zJyCGqjovaiIwt437MGOpY+gdYRqEuHxG+92IxJ4g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=qKGlviK5xYk04C2lyVCHyKZBcGL9E7iLkowdylt/Pd9lgYiOOlQMZRySn4g3ix16NRTHBNdES9gJdZY9ngBHe0QY1YeZhjVflq+rQysz0nsD8N0C36egpTHr0TZ7lgTSWNj8Th6XqmF3q/v89a3Z9SFeCbtU9Z5MWbWmpQWCU3Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=dxydN7sb; arc=none smtp.client-ip=91.218.175.183 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="dxydN7sb" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1778735447; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KfBmWLVLAOipY3O8m0a/fBCDqmiOi2Nx5QlLflxw4E0=; b=dxydN7sbiNIy8HQc7UmyMtvgBv3e5JAwv6K8Lr/cWgPPHvbprVEWJsSG9p9LXpN4dJ+k8N Qp+x9l2528f0ieQgpFC8oHebmqttNJ/VivNIQX7YlzH8uahIJy47nARSy2md3ONrIrwh8+ A8P+EyqmrNowraN/fgxzq+Y8hZckvNc= From: Jiayuan Chen To: bpf@vger.kernel.org Cc: Jiayuan Chen , Kuniyuki Iwashima , Eric Dumazet , Neal Cardwell , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Jiri Olsa , Shuah Khan , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: [PATCH bpf-next v4 2/2] selftests/bpf: verify syncookie statistics in tcp_custom_syncookie Date: Thu, 14 May 2026 13:09:58 +0800 Message-ID: <20260514051015.177926-3-jiayuan.chen@linux.dev> In-Reply-To: <20260514051015.177926-1-jiayuan.chen@linux.dev> References: <20260514051015.177926-1-jiayuan.chen@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Add read_tcpext_snmp() helper to network_helpers which reads a TcpExt SNMP counter via nstat, and use it in the tcp_custom_syncookie test to verify that LINUX_MIB_SYNCOOKIESRECV is incremented and LINUX_MIB_SYNCOOKIESFAILED stays unchanged across a successful BPF custom syncookie validation. The delta is captured between start_server() and accept(), which covers the full SYN/ACK/cookie-check path for one connection. Signed-off-by: Jiayuan Chen Reviewed-by: Kuniyuki Iwashima --- tools/testing/selftests/bpf/network_helpers.c | 22 +++++++++++++++++++ tools/testing/selftests/bpf/network_helpers.h | 1 + .../bpf/prog_tests/tcp_custom_syncookie.c | 20 +++++++++++++++++ 3 files changed, 43 insertions(+) diff --git a/tools/testing/selftests/bpf/network_helpers.c b/tools/testing/selftests/bpf/network_helpers.c index b82f572641b7d..4e3848f60261e 100644 --- a/tools/testing/selftests/bpf/network_helpers.c +++ b/tools/testing/selftests/bpf/network_helpers.c @@ -621,6 +621,28 @@ int get_socket_local_port(int sock_fd) return -1; } +int read_tcpext_snmp(const char *name, unsigned long *val) +{ + char cmd[128], buf[128]; + int ret = 0; + FILE *f; + + snprintf(cmd, sizeof(cmd), + "nstat -azs TcpExt%s | awk '/TcpExt/ {print $2}'", name); + f = popen(cmd, "r"); + if (!f) + return -errno; + + if (!fgets(buf, sizeof(buf), f)) { + ret = ferror(f) ? -errno : -ENODATA; + goto out; + } + *val = strtoul(buf, NULL, 10); +out: + pclose(f); + return ret; +} + int get_hw_ring_size(char *ifname, struct ethtool_ringparam *ring_param) { struct ifreq ifr = {0}; diff --git a/tools/testing/selftests/bpf/network_helpers.h b/tools/testing/selftests/bpf/network_helpers.h index 79a010c88e11c..c53cd781df6e6 100644 --- a/tools/testing/selftests/bpf/network_helpers.h +++ b/tools/testing/selftests/bpf/network_helpers.h @@ -84,6 +84,7 @@ int make_sockaddr(int family, const char *addr_str, __u16 port, struct sockaddr_storage *addr, socklen_t *len); char *ping_command(int family); int get_socket_local_port(int sock_fd); +int read_tcpext_snmp(const char *name, unsigned long *val); int get_hw_ring_size(char *ifname, struct ethtool_ringparam *ring_param); int set_hw_ring_size(char *ifname, struct ethtool_ringparam *ring_param); diff --git a/tools/testing/selftests/bpf/prog_tests/tcp_custom_syncookie.c b/tools/testing/selftests/bpf/prog_tests/tcp_custom_syncookie.c index eaf441dc7e79b..00d5c32674fc9 100644 --- a/tools/testing/selftests/bpf/prog_tests/tcp_custom_syncookie.c +++ b/tools/testing/selftests/bpf/prog_tests/tcp_custom_syncookie.c @@ -91,12 +91,21 @@ static void transfer_message(int sender, int receiver) static void create_connection(struct test_tcp_custom_syncookie_case *test_case) { + unsigned long failed_before, failed_after; + unsigned long recv_before, recv_after; int server, client, child; server = start_server(test_case->family, test_case->type, test_case->addr, 0, 0); if (!ASSERT_NEQ(server, -1, "start_server")) return; + if (!ASSERT_OK(read_tcpext_snmp("SyncookiesRecv", &recv_before), + "read SyncookiesRecv before")) + goto close_server; + if (!ASSERT_OK(read_tcpext_snmp("SyncookiesFailed", &failed_before), + "read SyncookiesFailed before")) + goto close_server; + client = connect_to_fd(server, 0); if (!ASSERT_NEQ(client, -1, "connect_to_fd")) goto close_server; @@ -105,9 +114,20 @@ static void create_connection(struct test_tcp_custom_syncookie_case *test_case) if (!ASSERT_NEQ(child, -1, "accept")) goto close_client; + if (!ASSERT_OK(read_tcpext_snmp("SyncookiesRecv", &recv_after), + "read SyncookiesRecv after")) + goto close_child; + if (!ASSERT_OK(read_tcpext_snmp("SyncookiesFailed", &failed_after), + "read SyncookiesFailed after")) + goto close_child; + + ASSERT_EQ(recv_after - recv_before, 1, "SyncookiesRecv delta"); + ASSERT_EQ(failed_after - failed_before, 0, "SyncookiesFailed delta"); + transfer_message(client, child); transfer_message(child, client); +close_child: close(child); close_client: close(client); -- 2.43.0