From owner-svn-src-all@freebsd.org Wed Jun 26 20:11:53 2019 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 4FFC815D0FC6; Wed, 26 Jun 2019 20:11:53 +0000 (UTC) (envelope-from markj@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 E73C085F95; Wed, 26 Jun 2019 20:11:52 +0000 (UTC) (envelope-from markj@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 C497C4DB3; Wed, 26 Jun 2019 20:11:52 +0000 (UTC) (envelope-from markj@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x5QKBqlC065477; Wed, 26 Jun 2019 20:11:52 GMT (envelope-from markj@FreeBSD.org) Received: (from markj@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x5QKBq5e065476; Wed, 26 Jun 2019 20:11:52 GMT (envelope-from markj@FreeBSD.org) Message-Id: <201906262011.x5QKBq5e065476@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: markj set sender to markj@FreeBSD.org using -f From: Mark Johnston Date: Wed, 26 Jun 2019 20:11:52 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r349438 - head/sbin/dhclient X-SVN-Group: head X-SVN-Commit-Author: markj X-SVN-Commit-Paths: head/sbin/dhclient X-SVN-Commit-Revision: 349438 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: E73C085F95 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.97 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.999,0]; NEURAL_HAM_SHORT(-0.97)[-0.966,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US]; NEURAL_HAM_LONG(-1.00)[-1.000,0] 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: Wed, 26 Jun 2019 20:11:53 -0000 Author: markj Date: Wed Jun 26 20:11:52 2019 New Revision: 349438 URL: https://svnweb.freebsd.org/changeset/base/349438 Log: Avoid a divide-by-zero when bad checksum counters overflow. A mixture of IP or UDP packets with valid and invalid checksum could cause {ip,udp}_packets_bad_checksum to wrap around to 0, resulting in a division by zero. This is packet.c rev. 1.27 from OpenBSD. admbugs: 552 Obtained from: OpenBSD MFC after: 3 days Modified: head/sbin/dhclient/packet.c Modified: head/sbin/dhclient/packet.c ============================================================================== --- head/sbin/dhclient/packet.c Wed Jun 26 20:07:16 2019 (r349437) +++ head/sbin/dhclient/packet.c Wed Jun 26 20:11:52 2019 (r349438) @@ -183,7 +183,7 @@ decode_udp_ip_header(unsigned char *buf, int bufix, st ip_packets_seen++; if (wrapsum(checksum(buf + bufix, ip_len, 0)) != 0) { ip_packets_bad_checksum++; - if (ip_packets_seen > 4 && + if (ip_packets_seen > 4 && ip_packets_bad_checksum != 0 && (ip_packets_seen / ip_packets_bad_checksum) < 2) { note("%d bad IP checksums seen in %d packets", ip_packets_bad_checksum, ip_packets_seen); @@ -235,7 +235,7 @@ decode_udp_ip_header(unsigned char *buf, int bufix, st udp_packets_seen++; if (usum && usum != sum) { udp_packets_bad_checksum++; - if (udp_packets_seen > 4 && + if (udp_packets_seen > 4 && udp_packets_bad_checksum != 0 && (udp_packets_seen / udp_packets_bad_checksum) < 2) { note("%d bad udp checksums in %d packets", udp_packets_bad_checksum, udp_packets_seen);