From owner-freebsd-net@freebsd.org Tue Nov 12 21:46:55 2019 Return-Path: Delivered-To: freebsd-net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 72B491BC634 for ; Tue, 12 Nov 2019 21:46:55 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mailman.nyi.freebsd.org (mailman.nyi.freebsd.org [IPv6:2610:1c1:1:606c::50:13]) by mx1.freebsd.org (Postfix) with ESMTP id 47CLtR2Vc9z49QP for ; Tue, 12 Nov 2019 21:46:55 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: by mailman.nyi.freebsd.org (Postfix) id 533641BC633; Tue, 12 Nov 2019 21:46:55 +0000 (UTC) Delivered-To: net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 52EB51BC632 for ; Tue, 12 Nov 2019 21:46:55 +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) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 47CLtR1cJNz49QM for ; Tue, 12 Nov 2019 21:46:55 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 17DC86226 for ; Tue, 12 Nov 2019 21:46:55 +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 xACLksaQ007998 for ; Tue, 12 Nov 2019 21:46:54 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id xACLksFP007997 for net@FreeBSD.org; Tue, 12 Nov 2019 21:46:54 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 235607] Incorrect checksums with NAT on vtnet with offloading Date: Tue, 12 Nov 2019 21:46:54 +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: 12.0-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: mike@sentex.net X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: net@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Nov 2019 21:46:55 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D235607 mike@sentex.net changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |mike@sentex.net --- Comment #10 from mike@sentex.net --- (In reply to Vincenzo Maffione from comment #9) wow, this is the problem I got caught up in this morning I think. A bunch = of FreeBSD VMs in KVM (Ubuntu 18.x). FreeBSD firewall with vtnet0 and vtnet1 VTNET0 is the public IP and VTNET1 connected a bunch of internal VMs. Going out from the gateway VM was not an issue. However, VMs behind the gat= eway could not establish TCP connections. On a remote host, the SYN packet would get to the host, but the host would never respond with a SYN-ACK... It would just ignore the SYN. When I switched all the devices to em NICs instead of VTNET, everything worked as expected.=20 A good connection initiated from the gateway across the public IP looked li= ke xxx.yyy.135.74.36086 > AAA.BBB.148.55.22: Flags [S], cksum 0xbf90 (correct= ), seq 489690757, win 65535, options [mss 1460,nop,wscale 6,sackOK,TS val 3421165670 ecr 0], length 0 and the bad connection with the vtnet trying to nat the internal VM as seen= at the external host 16:12:39.071314 IP (tos 0x10, ttl 60, id 0, offset 0, flags [DF], proto TCP (6), length 60) xxx.yyy.135.74.50993 > AAA.BBB.148.55.22: Flags [S], cksum 0x521b (incorrect -> 0x88ab), seq 515367701, win 65535, options [mss 1460,nop,wsca= le 6,sackOK,TS val 898080092 ecr 0], length 0 bad checksum.... --=20 You are receiving this mail because: You are the assignee for the bug.=