From nobody Thu Aug 6 09:09:15 2026 X-Original-To: net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4hG1gJ1kmkz6mh3C for ; Thu, 06 Aug 2026 09:09:16 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "YR1" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4hG1gJ0J9jz3ZSr for ; Thu, 06 Aug 2026 09:09:16 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1786007356; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jJOi1nMlNTGlkLfgFBb1yt14cMVRn/sWP7G2dJB7b6Q=; b=NBXNayP/DP/QCpF0S9nnmVGArALPsWhL/mLqBVESvPWnkB+aioKLjgl6EM+Vs8L2LyFei4 P8++aFwJDNOrj32U7VFXkfQhyNZlR5eOfLLcyjkuPIZPuY68Ze8JiSauSyhrllxMAL89q4 GO7HTdlRZtxmPUtBQJb6BQTphdCIpILjhMhmjTZnFWeFMjSSQIrvJSXMRzcwnLvJYbVu1V lI48asXzjV/Sg31ongtacr34WzMixOPz0tp+4TGtkJi4aSscoJRp0lKI70PEj0swxNm1wt BwOXFWkzb/2lZe4H9U6HGxzVUVHfSY/H4rjQ/cfgwjBfceaTFyjpSLij/kgemg== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1786007356; a=rsa-sha256; cv=none; b=Iqdk8bwYlMnF1qQh59E/5xbVmLVmSIjX8vfGNg2q9k4YLcDKOzziG+/SSPPp14kozkKT4m 1fZjWDc6plRe/5j5mRQ3GjrPJbZYBI2DJI0Ae8DynTStdnz2yhNzg7No3kwBvZP8lmTZKH wSrqo2E9HecZIb+IY0tViRYu4pa+oAlYz8C0BYYzXMEAPSNzA06uaYZMZmPDiFiBaCSIDz eHTJtnxW15RCkLo9h8/1lNJSbvkdMIpZM/4IB25dP78VicGvQE7MX04OXYPENI0l1/ux7R EGsrY4300qGNBeLSN0l4d1OWOBiqGSxSqqmWANp10is8v+1ADWBSZIFYsLQgmw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1786007356; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=jJOi1nMlNTGlkLfgFBb1yt14cMVRn/sWP7G2dJB7b6Q=; b=bSuxcR/+k4p+bZJZW7lGRB54CTOPTcrt1hjhr909B+FcFwg15AOcVC+1N41KIdo+5bJ83P JDxoUmbkhBVnCI3pTXTNoaLPRCZPejQ/iz9DPKZEI/1mjZh/K0V5BII3oGOlEKQl9q7+nT 3fPi/zhfZ5kuT4bNl52NACViYJWRs+EGdffnylhSx6RMWd7Vp41/K8yZUwDyi3CbBXMnMt g1hsQGXR/dFh2214W8kSWtdhoDUKEF4AHkWeCRmDOg+D45R+FOxao2cdXkGtFjDRo/Vp3u 0e7CBvc1UXuKhetwzpo4eH3Y4XNPRs5B4I54klVAW1f8CVTpmtsFISY95apIAA== Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4hG1gH5fgsz5R for ; Thu, 06 Aug 2026 09:09:15 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 67699FKe078325 for ; Thu, 6 Aug 2026 09:09:15 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from bugzilla@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 67699FST078324 for net@FreeBSD.org; Thu, 6 Aug 2026 09:09:15 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: bugzilla set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: net@FreeBSD.org Subject: [Bug 296594] TCP: RFC 5961 sends a challenge ACK instead of resetting when a valid RST arrives with SEG.SEQ == RCV.NXT and the receiver has delayed-ACKed data, leaving the connection half-open Date: Thu, 06 Aug 2026 09:09:15 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 16.0-CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: commit-hook@FreeBSD.org X-Bugzilla-Status: In Progress X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: tuexen@freebsd.org X-Bugzilla-Flags: mfc-stable15? mfc-stable14? X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="UTF-8" X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@FreeBSD.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D296594 --- Comment #11 from commit-hook@FreeBSD.org --- A commit in branch stable/15 references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=3D9ac39192d49643def7958961e4a55f9f9= d4b0c11 commit 9ac39192d49643def7958961e4a55f9f9d4b0c11 Author: Michael Tuexen AuthorDate: 2026-08-03 11:07:32 +0000 Commit: Michael Tuexen CommitDate: 2026-08-06 09:07:41 +0000 tcp: improve SEG.SEQ validation for RST segments A RST segment can be sent in response to (a) received segment or (b) by the upper layer protocol. The SEG.SEQ validation consists of two checks: (1) the in-window check of SEG.SEQ and (2) the exact match check of SEG.SEQ. For the in-window check (1), the left edge of the window needs to be based on tp->last_ack_sent to cover the delayed ACK case, whereas the right edge needs to be based on tp->rcv_nxt + tp->rcv_wnd. This both assumes that tp->rcv_wnd is not zero. For the special case of tp->rcv_wnd being zero, add checks against tp->last_ack_sent for (a) and on tp->rcv_nxt for (b). This applies to all TCP stacks. When the exact match (2) of SEG.SEQ is performed, it should be based on tp->last_ack_sent for (a) and on tp->rcv_nxt for (b). To cover both, check for both. Add this only to the base stack, since the RACK and BBR stacks already do this. PR: 296594 Reviewed by: rscheff Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D58594 (cherry picked from commit c9df1a6cf9be9d44eacc8616ebba1cd19010c7fc) sys/netinet/tcp_input.c | 18 ++++++++++++------ sys/netinet/tcp_stacks/rack_bbr_common.c | 22 ++++++++++++++-------- 2 files changed, 26 insertions(+), 14 deletions(-) --=20 You are receiving this mail because: You are on the CC list for the bug.=