From owner-svn-src-all@freebsd.org Thu Nov 8 21:58:52 2018 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A7E5A11081E4; Thu, 8 Nov 2018 21:58:52 +0000 (UTC) (envelope-from gjb@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 5774F6F90A; Thu, 8 Nov 2018 21:58:52 +0000 (UTC) (envelope-from gjb@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (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 395EE2877; Thu, 8 Nov 2018 21:58:52 +0000 (UTC) (envelope-from gjb@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id wA8Lwq0U093192; Thu, 8 Nov 2018 21:58:52 GMT (envelope-from gjb@FreeBSD.org) Received: (from gjb@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id wA8Lwqc7093191; Thu, 8 Nov 2018 21:58:52 GMT (envelope-from gjb@FreeBSD.org) Message-Id: <201811082158.wA8Lwqc7093191@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: gjb set sender to gjb@FreeBSD.org using -f From: Glen Barber Date: Thu, 8 Nov 2018 21:58:52 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r340268 - stable/11/sys/netinet X-SVN-Group: stable-11 X-SVN-Commit-Author: gjb X-SVN-Commit-Paths: stable/11/sys/netinet X-SVN-Commit-Revision: 340268 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 5774F6F90A X-Spamd-Result: default: False [-106.86 / 200.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; ALLOW_DOMAIN_WHITELIST(-100.00)[FreeBSD.org]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[4]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; TO_DN_NONE(0.00)[]; HAS_XAW(0.00)[]; R_SPF_SOFTFAIL(0.00)[~all]; DMARC_NA(0.00)[FreeBSD.org]; RCVD_COUNT_THREE(0.00)[4]; MX_GOOD(-0.01)[cached: mx1.FreeBSD.org]; NEURAL_HAM_SHORT(-1.00)[-1.000,0]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; RCVD_TLS_LAST(0.00)[]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; IP_SCORE(-3.75)[ip: (-9.91), ipnet: 2610:1c1:1::/48(-4.92), asn: 11403(-3.83), country: US(-0.09)] X-Rspamd-Server: mx1.freebsd.org X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 08 Nov 2018 21:58:53 -0000 Author: gjb Date: Thu Nov 8 21:58:51 2018 New Revision: 340268 URL: https://svnweb.freebsd.org/changeset/base/340268 Log: MFC r340260 (emaste): Avoid buffer underwrite in icmp_error icmp_error allocates either an mbuf (with pkthdr) or a cluster depending on the size of data to be quoted in the ICMP reply, but the calculation failed to account for the additional padding that m_align may apply. Include the ip header in the size passed to m_align. On 64-bit archs this will have the net effect of moving everything 4 bytes later in the mbuf or cluster. This will result in slightly pessimal alignment for the ICMP data copy. Also add an assertion that we do not move m_data before the beginning of the mbuf or cluster. Approved by: re (kib, insta-MFC) Security: CVE-2018-17156 Sponsored by: The FreeBSD Foundation Modified: stable/11/sys/netinet/ip_icmp.c Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/netinet/ip_icmp.c ============================================================================== --- stable/11/sys/netinet/ip_icmp.c Thu Nov 8 21:58:23 2018 (r340267) +++ stable/11/sys/netinet/ip_icmp.c Thu Nov 8 21:58:51 2018 (r340268) @@ -310,7 +310,8 @@ stdreply: icmpelen = max(8, min(V_icmp_quotelen, ntohs #endif icmplen = min(icmplen, M_TRAILINGSPACE(m) - sizeof(struct ip) - ICMP_MINLEN); - m_align(m, ICMP_MINLEN + icmplen); + m_align(m, sizeof(struct ip) + ICMP_MINLEN + icmplen); + m->m_data += sizeof(struct ip); m->m_len = ICMP_MINLEN + icmplen; /* XXX MRT make the outgoing packet use the same FIB @@ -352,6 +353,8 @@ stdreply: icmpelen = max(8, min(V_icmp_quotelen, ntohs * reply should bypass as well. */ m->m_flags |= n->m_flags & M_SKIP_FIREWALL; + KASSERT(M_LEADINGSPACE(m) >= sizeof(struct ip), + ("insufficient space for ip header")); m->m_data -= sizeof(struct ip); m->m_len += sizeof(struct ip); m->m_pkthdr.len = m->m_len;