From owner-freebsd-security@freebsd.org Tue Apr 21 23:55:33 2020 Return-Path: Delivered-To: freebsd-security@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 497DB2BE62D for ; Tue, 21 Apr 2020 23:55:33 +0000 (UTC) (envelope-from carpeddiem@gmail.com) Received: from mail-io1-f48.google.com (mail-io1-f48.google.com [209.85.166.48]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 496L6X3xkJz4PDp; Tue, 21 Apr 2020 23:55:32 +0000 (UTC) (envelope-from carpeddiem@gmail.com) Received: by mail-io1-f48.google.com with SMTP id f3so511796ioj.1; Tue, 21 Apr 2020 16:55:32 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=aRb9PwSM5QnsnlcPfatBEm41ignAVvPLYItT98IyCyo=; b=J8qZUBAPpbGxVA5hw0PcJq8QPhtK0zOQc/+09/uuQOXBAQ1xpE2+vKrdRIxfdlKBVh pNUiAOkyOratAIrMQKv4zJWkDqk92p4jjl1yGTOyaqbcg1LupYZEzg92PIvfMp1LYJfa RE/nyZBW1+aArG83pmtWg53YZVtDzkzCDgsBHMJIFE/5L8D65H+fwVcc2ovHsClX4jgX nscxt1t7HiCoI/mOO0awIB8XsxrnldJbaelAf9AGw3RObV3gMEnO42t7FGWPadc1PbsZ zkdJmYxH6zFo9A+pbt3Fgh0zw6XxQiOORpCUEHunohAV6ui04JQ8lcliSFFtlvlatUgl lVAQ== X-Gm-Message-State: AGi0PuYXsOzmBnM/HRBzbXcrJpY09mfS1Y/gDa5dNu8o40IHgH8GfNUl VZK+aQaw++RYgQwuOuPJh0u7ZO4vNdh2KGnZ315/uW+q X-Google-Smtp-Source: APiQypJVWprjK9e+phF7qCrybPf7V4Te/5KbCBwHIuN+1b18ZmVQam/pcmaQ4B+A1JRf196lghAbqW+2ISyaV4VVIUE= X-Received: by 2002:a05:6638:a47:: with SMTP id 7mr617436jap.12.1587513331119; Tue, 21 Apr 2020 16:55:31 -0700 (PDT) MIME-Version: 1.0 References: <20200421165514.C676C1CB78@freefall.freebsd.org> <54bfc0f6-be4c-349d-df87-8ba507803a04@grosbein.net> In-Reply-To: From: Ed Maste Date: Tue, 21 Apr 2020 19:55:18 -0400 Message-ID: Subject: Re: [FreeBSD-Announce] FreeBSD Security Advisory FreeBSD-SA-20:10.ipfw To: Eugene Grosbein Cc: "Andrey V. Elsukov" , freebsd-security@freebsd.org Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 496L6X3xkJz4PDp X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of carpeddiem@gmail.com designates 209.85.166.48 as permitted sender) smtp.mailfrom=carpeddiem@gmail.com X-Spamd-Result: default: False [-3.46 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; R_SPF_ALLOW(-0.20)[+ip4:209.85.128.0/17]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[freebsd.org]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RCVD_IN_DNSWL_NONE(0.00)[48.166.85.209.list.dnswl.org : 127.0.5.0]; IP_SCORE(-1.46)[ip: (-6.45), ipnet: 209.85.128.0/17(-0.40), asn: 15169(-0.43), country: US(-0.05)]; FORGED_SENDER(0.30)[emaste@freebsd.org,carpeddiem@gmail.com]; RWL_MAILSPIKE_POSSIBLE(0.00)[48.166.85.209.rep.mailspike.net : 127.0.0.17]; MIME_TRACE(0.00)[0:+]; R_DKIM_NA(0.00)[]; FREEMAIL_ENVFROM(0.00)[gmail.com]; ASN(0.00)[asn:15169, ipnet:209.85.128.0/17, country:US]; FROM_NEQ_ENVFROM(0.00)[emaste@freebsd.org,carpeddiem@gmail.com]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Apr 2020 23:55:33 -0000 On Tue, 21 Apr 2020 at 18:50, Eugene Grosbein wrote: > > > I believe this is correct; what about this statement: > > > > No workaround is available. Systems not using the ipfw firewall, and > > systems that use the ipfw firewall but without any rules using "tcpoptions" > > or "tcpmss" keywords, are not affected. > > Isn't removing rules with "tcpoptions/tcpmss" considered as work-around? > > Such rules may be replaced with "ipfw netgraph" rules and processing TCP options > with NETGRAPH node ng_bpf(4). Seems as work-around to me. Fair enough, although I don't want to provide that as an official suggestion in the advisory without testing and understanding the caveats, so probably just removing the "No workaround is available." So perhaps: Systems not using the ipfw firewall, and systems that use the ipfw firewall but with no rules using "tcpoptions" or "tcpmss" keywords, are not affected.