From nobody Fri Apr 3 12:38:27 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 CEA6B15539A; Thu, 19 Feb 2026 23:56:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771545364; cv=none; b=gA6Iv1XRfkVE576gJlbQnwzK+ZpnOaToS+0IREDXKBZL4PNldHH5T8g/tw96sfKfC709ghJnJVusBog0pqNLUQqFudeoOrWMaSF4+axJx6Oossq3nNq0fHmPuqqWZfZc55ZE1VNcAEN0Aud+ZDGZ6Mm8xy+tg4Orey1V3xYCbsU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771545364; c=relaxed/simple; bh=W4+lTtQg9XK2AMyVTLl5/C3YX/X14q1QnU9K2rdiGfM=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=rOTcum6COGlwSyy7ktpcWBYzgHv7t/orYLdVrWxtX4fjJXRen6YCJFD9cy2DBrc8UqESJSwTPBG1r6r/vg8gzdf4DDuPIRmJu9TW2O5nrgj07hSf5wsv/l72HDc8NsNnFuwOqm7u76u4mSPCU/bqzzOK5N3AXSXLrUbBt3Q7Qko= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZqZ9+qsJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZqZ9+qsJ" Received: by smtp.kernel.org (Postfix) with ESMTPS id A151DC2BC87; Thu, 19 Feb 2026 23:56:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771545364; bh=W4+lTtQg9XK2AMyVTLl5/C3YX/X14q1QnU9K2rdiGfM=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=ZqZ9+qsJ7zOUH1OAdo3wIjwSIygpVGra27qCSgAIacM/KVMYYDVxzHQDiAgFrN2E9 XZF2p8e4yUp6VBnTbX2w6RzDVBwBtVS7QDvzoyu2WH5Leajt0/vbW1l415x/2tknQr iXviLEV4ON/sG5OL1J71wgnDXN94ihihmMO6QYy8ItDsEPooQZ50u/4PWDikVia5m+ r+wsPlSAR1ehtgaSmQMy8ErIVB2K6bsp/xt1mdCimXWOWwFZVA0SfqIbpiAk7GHQT5 XAL+h86iw1fiLdZTuCPp6Q1+Eg/5YMp5zKzFB1+Rvl7jNLX9XQFKOwOt7UbvrPBS8C XA2LoSXj+EioA== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 96478C531F3; Thu, 19 Feb 2026 23:56:04 +0000 (UTC) From: Simon Baatz via B4 Relay Date: Fri, 20 Feb 2026 00:55:17 +0100 Subject: [PATCH RFC net-next 4/4] selftests/net: packetdrill: add tcp_rcv_toobig_back_to_back.pkt Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260220-tcp_rfc7323_retract_wnd_rfc-v1-4-904942561479@gmail.com> References: <20260220-tcp_rfc7323_retract_wnd_rfc-v1-0-904942561479@gmail.com> In-Reply-To: <20260220-tcp_rfc7323_retract_wnd_rfc-v1-0-904942561479@gmail.com> To: Eric Dumazet , Neal Cardwell , Kuniyuki Iwashima , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , Jonathan Corbet , Shuah Khan , David Ahern , Stefano Brivio , Jon Maloy , Jason Xing , mfreemon@cloudflare.com, Shuah Khan Cc: Christian Ebner , netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Simon Baatz X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1771545363; l=1646; i=gmbnomis@gmail.com; s=20260220; h=from:subject:message-id; bh=c1eQDsHINo/iLpDzO11WhQUeLWxzIkGGeSmjjLGkjpQ=; b=tGiZqmdvVs1iMDN93UHdsZnv90evQhVamdSvCoez+vPECABVnnhvp0nW717BsblYUJtRlcHaH oPH4k/Yj/LuCnEItmj3gZHey/IHNif1Hx88V/lBkZm2UFDkSKgvE2qo X-Developer-Key: i=gmbnomis@gmail.com; a=ed25519; pk=T/JIz/6F5bf1uQJr69lmyi7czVG+F9TVZ/8x5z9Wtqw= X-Endpoint-Received: by B4 Relay for gmbnomis@gmail.com/20260220 with auth_id=641 X-Original-From: Simon Baatz Reply-To: gmbnomis@gmail.com From: Simon Baatz This test verifies the sequence number checks using the maximum advertised window sequence number when we accept a packet going beyond any window that was ever advertised (i.e. rcv_nxt advances beyond rcv_mwnd_seq). Signed-off-by: Simon Baatz --- .../packetdrill/tcp_rcv_toobig_back_to_back.pkt | 27 ++++++++++++++++++= ++++ 1 file changed, 27 insertions(+) diff --git a/tools/testing/selftests/net/packetdrill/tcp_rcv_toobig_back_to= _back.pkt b/tools/testing/selftests/net/packetdrill/tcp_rcv_toobig_back_to_= back.pkt new file mode 100644 index 0000000000000000000000000000000000000000..4d4c33d248948d3dfaf9b0c5b24= 3ed27321e9b10 --- /dev/null +++ b/tools/testing/selftests/net/packetdrill/tcp_rcv_toobig_back_to_back.p= kt @@ -0,0 +1,27 @@ +// SPDX-License-Identifier: GPL-2.0 + +--mss=3D1000 + +`./defaults.sh` + +// Establish a connection. + +0 socket(..., SOCK_STREAM, IPPROTO_TCP) =3D 3 + +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) =3D 0 + +0 setsockopt(3, SOL_SOCKET, SO_RCVBUF, [20000], 4) =3D 0 + +0 bind(3, ..., ...) =3D 0 + +0 listen(3, 1) =3D 0 + + +0 < S 0:0(0) win 32792 + +0 > S. 0:0(0) ack 1 win 18980 + +.1 < . 1:1(0) ack 1 win 257 + + +0 accept(3, ..., ...) =3D 4 + +// A too big packet is accepted if the receive queue is empty + +0 < P. 1:20001(20000) ack 1 win 257 +// Send a RST immediately so that there is no rcv_wup/rcv_mwnd_seq update = yet + +0 < R. 20001:20001(0) ack 1 win 257 +// * > . 1:1(0) ack 20001 win 18000 + + +.1 %{ assert tcpi_state =3D=3D TCP_CLOSE, tcpi_state }% + --=20 2.52.0