From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f202.google.com (mail-qk1-f202.google.com [209.85.222.202]) (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 2E51C212D7C for ; Fri, 13 Mar 2026 11:54:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773402873; cv=none; b=CVCZ15lI9U2rtr9bJL5ogz7kYWL/mn6Z7v59T7KJvdDdI3uFtKwZyzv44zGZ6IwGg6iNvvq4b/CTW9CvLJ9PPVo5r4e9Cw+9xaaDNeZq0pC8C7p8clfDncrDbKm9hxl2vladxt449Rzru5VgBJyoHwghmaYJM8ZpTEb4EmvAtJQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773402873; c=relaxed/simple; bh=yuFNSvbd/GBD2Hea2tZ+VmOSRiEitFWDftzuSThsjR8=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=KZ6+YTJFAkFZ3+uFqQ0m3WD8F1CGuqxzBSpr80vSfvjlkU2b6Oqew0a2XddJ6yFH72RwkgzKonuBfj21qeuMaPw/mdDky57qym/aXH02iir+4s+zl4nHLa9n+C3mJzCUQPqDucKQe/ExQh+kIaxg5a+FLQ3T2Xnqo4/XPxatN6Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Am6yNwXK; arc=none smtp.client-ip=209.85.222.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Am6yNwXK" Received: by mail-qk1-f202.google.com with SMTP id af79cd13be357-8cd849cd562so1321043985a.0 for ; Fri, 13 Mar 2026 04:54:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1773402871; x=1774007671; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=5d0c+/jW+zBhRDYtm6gIQxc4BCZlre46j5/CC58kPwg=; b=Am6yNwXK58EeMUf41aLq6qu0oIzsigKwasN7KDkzQXUT/gswM4R+zSKDE6kWJgqHfP ogF4K3B1gFM0hrTYyyoobl+JBaPkX4QJSKbQomEuHIf7o9RLssL998h85i2/xptbJF/t RPvetdhXn/ifMDUX0rWQMQWglRbyU5QHHJTa7AM9Gq318/xSxZwkHKVFxysjEEz8u5Xr YTnjMnB5UlSKniSFjZpWZuwroYh7A6fo6879JdSV99w6lHM4A9Be5nwGdeF0dMTYsvC0 5/Mh6idYOOW6QrAok22uJQYh/+xyu4LNomod+sLtJqoOOq2ifSjefoXbts3xfZed2MZl ZzCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1773402871; x=1774007671; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=5d0c+/jW+zBhRDYtm6gIQxc4BCZlre46j5/CC58kPwg=; b=oNULS2xWca+zkv+2tbbRQFalvEv0q+6s+GA6A42LQqslwCmdyaeJ9c/BmCo61kN9B/ 4kXfxdXQ3ROKNJjBnzoGodFsTWYXvpoRz6ilLqlvApaSrSIyI0127dJtVp9mQsc99XQl EZZWGMhXtt7YAa+mtNy65/Vl+9DpNVBqoL5vDGh1gn0dtSwaQwHADlCE9HRizMP9Iupr ui0eMW0VkKmlPweb2osBERvw8RYNbLRzeLNagJX/bwEpz80iMSxPbfXjtQHWzZWltgz8 CBZn28VVmMkNMmewFSvyNoWfNPkEQLaK5JLd0wpDX4lKe8Swn8AAWvKSzBX7Q74DTwiw g2UQ== X-Forwarded-Encrypted: i=1; AJvYcCWsFXf3vNPyU+U5KYd4eSw4ehj6E3YMasIW4Li2ixNUWUDKQfAPbOo7MlmJSW/4a2XzVxtfRrs=@vger.kernel.org X-Gm-Message-State: AOJu0YzQNCe60fCZar4NQXmUNLF/iPbV07t/Y86Qx6zSuDjdrKKMYqk9 O5ZGijBtXPv4EkzItbGz9Ou0CW092ojLanNjhPgN7kpgtlyg10lfrNiCMFohOMbNKcaJGmvVHcZ 0zYUT4lOP4/8MFA== X-Received: from qkok7.prod.google.com ([2002:a05:620a:4147:b0:8cd:8b70:fdb]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:a05:620a:1a25:b0:8cd:94f9:1bcd with SMTP id af79cd13be357-8cdb5a502a3mr411489685a.12.1773402870772; Fri, 13 Mar 2026 04:54:30 -0700 (PDT) Date: Fri, 13 Mar 2026 11:54:29 +0000 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.53.0.880.g73c4285caa-goog Message-ID: <20260313115429.3365751-1-edumazet@google.com> Subject: [PATCH net-next] selftests/net: packetdrill: add tcp_disorder_fin_in_FIN_WAIT.pkt From: Eric Dumazet To: "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Neal Cardwell , Kuniyuki Iwashima , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet , Menglong Dong Content-Type: text/plain; charset="UTF-8" Commit 795a7dfbc3d9 ("net: tcp: accept old ack during closing") was fixing an old bug, add a test to make sure we won't break this case in future kernels. Signed-off-by: Eric Dumazet Cc: Menglong Dong --- .../tcp_disorder_fin_in_FIN_WAIT.pkt | 33 +++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 tools/testing/selftests/net/packetdrill/tcp_disorder_fin_in_FIN_WAIT.pkt diff --git a/tools/testing/selftests/net/packetdrill/tcp_disorder_fin_in_FIN_WAIT.pkt b/tools/testing/selftests/net/packetdrill/tcp_disorder_fin_in_FIN_WAIT.pkt new file mode 100644 index 0000000000000000000000000000000000000000..336cbf7815c86cfdbc44a3322413abf0bfed1516 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp_disorder_fin_in_FIN_WAIT.pkt @@ -0,0 +1,33 @@ +// SPDX-License-Identifier: GPL-2.0 + +// Check fix in 795a7dfbc3d9 ("net: tcp: accept old ack during closing") + +// Set up config. +`./defaults.sh` + +// Initialize a server socket. + 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 + +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 + +0 bind(3, ..., ...) = 0 + +0 listen(3, 1) = 0 + + +0 < S 0:0(0) win 65535 + * > S. 0:0(0) ack 1 + +0 < . 1:1(0) ack 1 win 257 + + +0 accept(3, ..., ...) = 4 + + +0 shutdown(4, SHUT_WR) = 0 + * > F. 1:1(0) ack 1 + +// We expect to receive one ACK. +// But what happens if a FIN was already in transmt and received out-of-order ? + + +0 < . 2:2(0) ack 2 win 257 + +// This FIN packet was sent before the prior ACK (see ack 1). + +0 < F. 1:1(0) ack 1 win 257 + +// Even if the FIN is received out-of-order, we should ACK it. + + * > . 2:2(0) ack 2 -- 2.53.0.880.g73c4285caa-goog