From nobody@FreeBSD.ORG  Sun Oct 22 22:55:38 2000
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Date: Sun, 22 Oct 2000 22:55:38 -0700 (PDT)
From: Stanley.Hopcroft@IPAustralia.GOv.AU
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Subject: When using tun interface (user PPP), tcpdump does not show incoming packets when used with a filter expression
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>Number:         22234
>Category:       misc
>Synopsis:       When using tun interface (user PPP), tcpdump does not show incoming packets when used with a filter expression
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          closed
>Quarter:        
>Keywords:       
>Date-Required:  
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Oct 22 23:00:01 PDT 2000
>Closed-Date:    Tue Oct 31 15:56:53 PST 2000
>Last-Modified:  Tue Oct 31 16:02:23 PST 2000
>Originator:     Stanley Hopcroft
>Release:        4.1-RELEASE (also 4.0-RELEASE)
>Organization:
IP Australia
>Environment:
FreeBSD stan.aipo.gov.au 4.1-RELEASE FreeBSD 4.1-RELEASE #0: Fri Sep  1 13:27:48 EST 2000     root@stan.aipo.gov.au:/usr/src/sys/compile/STAN2  i386

>Description:
tcpdump -itunX filter_expression shows only outgoing (from localhost)
packets.

It does not show any incoming packets.

Problem machine has only one serial interface.

Ethereal 8.xbehaves the same way.

Ethernet interfaces are not affected.

No NAT or IPFW or IPFILTER in place.


>How-To-Repeat:
tcpdump -itunX port telnet

when you have an open telnet connection shows only
the telnet client packets; there are no server reply packets.

tcpdump -itunX <Null_Filter_Expression ie Null String works fine but you get everything.

>Fix:
Same behaviour under 4.0-RELEASE.

Downgrade to 3.x I suspect.

>Release-Note:
>Audit-Trail:
State-Changed-From-To: open->closed 
State-Changed-By: brian 
State-Changed-When: Tue Oct 31 15:56:53 PST 2000 
State-Changed-Why:  
Fixed in -current, and just commited to -stable (net/if_tun.c 1.74.2.2) 

http://www.freebsd.org/cgi/query-pr.cgi?pr=22234 
>Unformatted:
