From nobody Sun Jun 8 18:16:06 2025 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 4bFjsz1DD4z5xvWc for ; Sun, 08 Jun 2025 18:16:07 +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 "R11" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4bFjsy4bTRz3krj for ; Sun, 08 Jun 2025 18:16:06 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1749406566; 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=ZCBkYgYs4t3WVq7dIIUyWnUtbUcGXiGUkjoOwNaegjs=; b=fw6p41SMjZ7/ufhOLDRYdNaOc7bcU1oqlY+xtJ4DPxiMq9TEwDQlolvgm1I+gI0bHcU5+H FmX93Ygmz386qM+MKzp4vefypkhNc1D0KqKTt6G9YuvVtpIZMwTh3N/p7UyvX4HhoStsne 2tGUc8LB3RE+5K25XLwkidQ85PsO4MvZ3vNjyrt2A8pH20ywdmDCIhJqDnI+7C54cXS8ym opYu049K9pFs9gykFNy38Us0yCgihFDcuusO4+zrmrAgmzgEhro+FWPTCEOml8wHqjgyKV ItT2/Kww6Idyp0GjsckneUhFvN3lDmqFjKa7dutTJBc5rY7Apn1jRXJjR5RoVA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1749406566; 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=ZCBkYgYs4t3WVq7dIIUyWnUtbUcGXiGUkjoOwNaegjs=; b=VJFfUPSCK2hyZzce95n6C+sIsYMoP9a23yZCZM2h9HJha020ciHOJN4/IZb+iBwp6LZ82/ lwuBFr8Emz2dLwyMUf0+7MjmPhS2ncjW/JA0AddvmQDE1Qw/SNor/GSYcH0k9hI5RWaAWU g3HbnwTkxLdlcuPhagPMYwgYfCyGA/lcPOLyfokJdU+yCqF/O4ANO4cx35p/TzRs4lLUgv 6bA72nRrA2YluwXHov8/m7yyf87AjvodkwQN0v3IV1NYDsCs9lHdAuuq6mihqUiQZ16T35 vKpXtjriW0nU3sPaeP6DyeldjY/M702bFOKvcyAXQ3Qc9ahTwpiNsDHNBUTj0A== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1749406566; a=rsa-sha256; cv=none; b=sFkej5wj/7aG4iQBQil7vni7CnxNJUHUbj+/GJ3VgEO5/fIXGqCdH7QULM0wSSt/LEYAcw d3VNQMZU52wrjZbE4dXEFSbwkt6FkkW8RUN0Uk4F+e3Q5j/JwlEhkBBH/6dtvwosVPJS3g ghBDqSfSbuvrGH2PTH7pVf4IWZx7EBslkled2VczNmi8p79TLxOl04HaL9I9n1bXWXWlL6 NEyYTt/9N/0dK/PwWZXHAw1KjZHCznpG3SFQ9GAo72vXmwf9V1TMLdpYAryxzQUFqeimEq Jea7jM03JvUjZMdB8gpQcVzOqPZs/Cst4tEkD+2T8eJQ8AMIXCYritovLC8oyQ== 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 4bFjsy3pwNz4bt for ; Sun, 08 Jun 2025 18:16:06 +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 558IG65i094659 for ; Sun, 8 Jun 2025 18:16:06 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 558IG6ai094658 for net@FreeBSD.org; Sun, 8 Jun 2025 18:16:06 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: net@FreeBSD.org Subject: [Bug 287229] IP reassembly issue in FreeBSD 14.1 Date: Sun, 08 Jun 2025 18:16:06 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 14.2-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: tuexen@freebsd.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: net@FreeBSD.org X-Bugzilla-Flags: 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 MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D287229 --- Comment #5 from Michael Tuexen --- I looked at the code and I think there are not much differences between 14.1 and CURRENT, at least for the IPv4 case, which I am focussing on. The reassembly algorithm is also deterministic and therefore looking into cases where you describe it as un-deterministic is interesting. But to be clear: deterministic means if the IPv4 stack reassembles the same sequence of incoming packets the same way. I have two questions for you: (1) how do you ensure that different test cases do not interfere? Manually selecting different IP IDs? (2) how do you ensure that the reassembly buffer is empty, before you start running a test? If fragments stay there, the second run has a different inp= ut. For example, test_495_peosp-oms, the reassembly can be performed after the first two packets have been received (see the corresponding y trace). So the last two fragments stay in the reassembly buffer. When you run the test aga= in, it looks receiving (in this sequence) the 3rd, 4th, 1st, 2nd, 3rd, 4th segm= ent. After the first four fragments, the packet is reassembled, but differently, since the sequence is different. I guess this results in an ICMP checksum e= rror and therefore you don't see the ICMP echo response. Maybe I can hack packetdrill a bit to test this locally. But right now I suspect that the cause for the difference in behavior is related to the reassembly buffer not being in the same state when running the tests. --=20 You are receiving this mail because: You are the assignee for the bug.=