From nobody Tue Jun 24 09:29:54 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 4bRKRQ60Z5z60XBZ for ; Tue, 24 Jun 2025 09:29:54 +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 "R10" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4bRKRQ4BGSz3c4N for ; Tue, 24 Jun 2025 09:29:54 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1750757394; 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=NXPBThS/gnayxzQYCdujyaWe1Ano34zmK/gz+R3VXD4=; b=t15AVZTdnzrKJY4HMtEijE0+uJThWOOYHfozFmiJuf1ogB7ZCBK12/lz4MD97TOVmIP/Oq AaPDYJhoojYchpeYnJZDq47OixMO3sDhQjJP2rqEPWCfZqIIc7NxR7M0UzEhLsVi2bDo5c 7gfVcvy06wgf96tWEJ1N7dqcbkfwE1a16TTv4jBRtaVT17CwF91xcviqMeFnmLgrmhCfab 41wo5tHwmuo8UtP2dNKgkQRhVr/d4l+eBMSvFfI9nQ1ShRivLZ3lqDK0YSqUfAu26gxGh1 QFlaERnuE1XLnMqqPqlqM5Aehi49sSntwSJL/VdGeoA1vWyM3pUQGrUMpicgJQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1750757394; 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=NXPBThS/gnayxzQYCdujyaWe1Ano34zmK/gz+R3VXD4=; b=Vpz2wkcIcVI+kAOPMPEIfwBhixboS+EXxXtzDtebZSnawzIai11m1ZFhGmLomyH7ZfppMv yq5YzofqRPEES/vDK3lRRExw0Ygh9J7+eu+N27Tpz/rH2Q3s9SJkddCspyjTXYz7bo38W9 5rBILN0ukrhjyZb6tFvcyRWqZTxhNrD2DX0L38/kEQIfr+ysh1yFxt/DtYCCLgWBFD88yk CHW2vemNViK22MRzwZxGU+peGwULouo8SWx8R5jAFS+Bh3TvpKlIEM4HA8jkSuqqZjiptL 25yn95Z7CGjGLHP2iVA3NOI2g2NjvXiTdYjdUGJUvVhlPandEkPNbcmxCZDHKg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1750757394; a=rsa-sha256; cv=none; b=jYHmu1XrAQFALk4h4cV8jhj2nq5BrROgW1SlCmdlPJsxAwAq6izvxKv0nCWbwNxrFLQSRL msBhy5k84KK+anegy+wwAZZt1xlkyEl3AAylhc9A7Ndzmathg6Xr1Y6lR8CMemZsmZ2EIF SRXmB/pT4Bl3jHZX1vi6Y7VtNk6DS3bVcAK04lUTnOu/D4TYrXape3v+vJ9veqTnN8+0VG eWzWR34+gFT1H9b1P/navG6PCHcqQt8aCH1tbV0rmIXiO7uHE/bJGXXTpMcQ6ABlSFbrh1 GNS1pCdkR5R7aIRPkzO1yWsnJW10thTAnnjq1yPy3o7ey4LNrQbbaRksV52t/A== 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 4bRKRQ37ndzjLx for ; Tue, 24 Jun 2025 09:29:54 +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 55O9TsQm010508 for ; Tue, 24 Jun 2025 09:29:54 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 55O9TsDj010507 for net@FreeBSD.org; Tue, 24 Jun 2025 09:29:54 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: Tue, 24 Jun 2025 09:29:54 +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: 14.2-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: lucas.aubard@irisa.fr X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: tuexen@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 #37 from Lucas Aubard --- (In reply to Michael Tuexen from comment #33) In the attacks we consider, the attacker does not try to reach FreeBSD limi= ts to force it to drop some fragments. Instead, the attacker sends a sequence = of overlapping packets that the NIDS and the supervised host reassemble differently (e.g., the NIDS favors the oldest data in the overlapping porti= on while the supervised host prefers the newest). Thus, the attacker does not = try to reproduce our entire set of test cases; they only need one of the test c= ases to perform the attack. In our testing, we are trying to obtain the FreeBSD reassembly policy, and = the limits are reached because of the VM setting and the testing parallelizatio= n.=20 For your information, here are the results of some experiments I ran with 4= 0 or 60 processes: - (1) vm.kmem_size=3D"200M", vm.kmem_size_max=3D"200M", maxfragbucketsize= =3D100, maxfrags=3D400 (default), 40 processes =3D> inconsistencies. - (2) vm.kmem_size=3D"200M", vm.kmem_size_max=3D"200M", maxfragbucketsize= =3D100, maxfrags=3D4000, 40 processes =3D> no inconsistency. - (3) vm.kmem_size=3D"200M", vm.kmem_size_max=3D"200M", maxfragbucketsize= =3D100, maxfrags=3D4000, 60 processes =3D> inconsistencies. - (4) vm.kmem_size=3D"1000M", vm.kmem_size_max=3D"1000M", maxfragbucketsize= =3D3 (default), maxfrags=3D1983 (default), 60 processes =3D> inconsistencies. - (5) vm.kmem_size=3D"1000M", vm.kmem_size_max=3D"1000M", maxfragbucketsize= =3D3 (default), maxfrags=3D4000, 60 processes =3D> no inconsistency. - (6) vm.kmem_size=3D"1000M", vm.kmem_size_max=3D"1000M", maxfragbucketsize= =3D100, maxfrags=3D4000, 60 processes =3D> inconsistencies. Let me know if you want that I test other parameter values. For my specific case, I should increase kmem_size to 2000M so as not to experience reassembly inconsistency. --=20 You are receiving this mail because: You are on the CC list for the bug.=