Bug 441446

Summary: double-count received packets
Product: Red Hat Enterprise Linux 5 Reporter: Tetsuo Takata <takata.tetsuo>
Component: tcpdumpAssignee: Miroslav Lichvar <mlichvar>
Status: CLOSED ERRATA QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: 5.1CC: eric.brower, maeno.masaki, mmalik, psklenar, sputhenp, tao
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2009-01-20 21:09:53 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 391501    
Attachments:
Description Flags
don't double-count received packets none

Description Tetsuo Takata 2008-04-08 06:07:23 UTC
From Bugzilla Helper:
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; ja; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13

Description of problem:
When the tcpdump command execution completes, it indicates the value of captured, filtered and dropped.
If no packets drops, the value of captured and filtered may be equal.

But the value of filtered is always double as many as captured in tcpdump-3.9.4-11.el5.

I think this is the bug of libpcap-0.9.4 in tcpdump-3.9.4 and fixed in the libpcap-0.9.5.

Please see the changelog of the tcpdump community.
--- quoted from http://www.tcpdump.org/libpcap-changes.txt ---
	Don't double-count received packets on Linux systems that 
	 support the PACKET_STATISTICS getsockopt() argument on 
	 PF_PACKET sockets.
--------------------------------------------------------------

Version-Release number of selected component (if applicable):
tcpdump-3.9.4-11.el5

How reproducible:
Always


Steps to Reproduce:
1. execute tcpdump commands.


Actual Results:
# tcpdump
<snip>
736 packets captured
1473 packets received by filter
0 packets dropped by kernel

Expected Results:
# tcpdump
<snip>
736 packets captured
736 packets received by filter
0 packets dropped by kernel


Additional info:

Comment 2 Miroslav Lichvar 2008-04-16 12:02:49 UTC
Created attachment 302587 [details]
don't double-count received packets

Comment 22 RHEL Program Management 2008-06-02 20:09:25 UTC
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release.  Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products.  This request is not yet committed for inclusion in an Update
release.

Comment 26 errata-xmlrpc 2009-01-20 21:09:53 UTC
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2009-0114.html