Date: Mon, 21 Apr 1997 17:29:54 -0700 (PDT) From: Chris Timmons <skynyrd@opus.cts.cwu.edu> To: FreeBSD-gnats-submit@freebsd.org Subject: bin/3371: LBL tcpdump 3.3 -merge submission Message-ID: <199704220029.RAA26136@opus.cts.cwu.edu> Resent-Message-ID: <199704220040.RAA01638@freefall.freebsd.org>
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Note: There was a bad value `sw-bug|change-request' for the field `>Class:'. It was set to the default value of `sw-bug'. >Number: 3371 >Category: bin >Synopsis: LBL tcpdump 3.3 -merge submission >Confidential: no >Severity: non-critical >Priority: medium >Responsible: freebsd-bugs >State: open >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Mon Apr 21 17:40:00 PDT 1997 >Last-Modified: >Originator: Chris Timmons >Organization: Central Washington University >Release: FreeBSD 3.0-CURRENT i386 >Environment: 3.0-CURRENT with recently repaired libpcap (see i386/3353.) >Description: Pre lbl-3.3 tcpdump (like the one in -current) mistakenly believes that the small udp packet is actually a truncated one because of a logic bug in print-udp.c (which probably produced correct results for the wrong reasons on interfaces which padded ethernet packets to ETHERMIN before the bpf_tap.) Of course nowadays we have more advanced hw that pads for us so the driver doesn't have to, and very short packets get shoved down the bpf_tap pipe to bring these bugs to light. But anyways: >How-To-Repeat: To see the bug, use netcat to query a udp time server, such as the one that inetd can run, and monitor the transaction from the same machine using tcpdump: nc -u -z -w 1 pahtoh time 15:54:37.024031 [|udp] 15:54:37.025030 pahtoh.cwu.edu.time > swash.cts.cwu.edu.1267: udp 4 Merged -current+lbl-3.3 correctly processes this: 15:57:39.021435 swash.cts.cwu.edu.1271 > pahtoh.cwu.edu.time: udp 1 15:57:39.022410 pahtoh.cwu.edu.time > swash.cts.cwu.edu.1271: udp 4 >Fix: tcpdump v3.3 from ftp.ee.lbl.gov fixes the problem. Since we are a release behind, I have done nearly all of the work necessary to merge this into -current and created a kit which I have uploaded as ftp://ftp.freebsd.org/pub/FreeBSD/incoming/tcpdump-to-lbl33-merge.tar.gz MD5 (tcpdump-to-lbl33-merge.tar.gz) = 7fa45cf54d5ce868d21bfeaecde55b3e The kit consists of a buildable reference tree that resulted from my local CVS merge (into a copy of the FreeBSD tree) of lbl-3.3 tcpdump, and a patch kit to address merge conflicts (a couple of -Wall patches are included separately.) A complete narrative of length war and peace is included which explains how this would be useful to someone really merging this into our tree. Normally the corresponding release of libpcap would be merged at the same time - I can do that, too, but would like some feedback on whether or not this kind of submission is useful or appropriate. >Audit-Trail: >Unformatted:
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