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Bug 234525 - wireshark claims UDP checksum failure for multicast
Summary: wireshark claims UDP checksum failure for multicast
Alias: None
Product: Fedora
Classification: Fedora
Component: wireshark
Version: 6
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Radek Vokal
QA Contact:
Depends On:
TreeView+ depends on / blocked
Reported: 2007-03-29 20:09 UTC by Steve Friedman
Modified: 2008-02-19 14:00 UTC (History)
0 users

Fixed In Version: wireshark-0.99.7
Doc Type: Bug Fix
Doc Text:
Clone Of:
Last Closed: 2008-02-19 14:00:41 UTC

Attachments (Terms of Use)

Description Steve Friedman 2007-03-29 20:09:08 UTC
Description of problem:
Whether I generate multicast packets from nc, socat, or syslog-ng,
wireshark/tshark detect a UDP CHECKSUM failure.

Version-Release number of selected component (if applicable):

How reproducible:
Every time.

Steps to Reproduce:
1. nc -u 12345
2. /usr/sbin/wireshark, and capture the identified packets
3. type something at the nc prompt
Actual results:
wireshark / tshark claims that the packet contains a UDP CHECKSUM failure.

Expected results:
No checksum error is detected.

Additional info:
I highly suspect that the kernel is generating the udp checksum, not the
applications.  However, here are the versions of the applications that were used
as well as the kernel:


Comment 1 Radek Vokal 2007-03-29 20:38:56 UTC
The only checksum problem I'm aware of is described here

is this the same problem? 

Comment 2 Steve Friedman 2007-03-29 20:45:59 UTC
No.  I've also captured this when the packets are generated from another machine.

Comment 3 Radek Vokal 2007-07-23 13:33:03 UTC
Wireshark was updated to 0.99.6 release. Please retest the issue with the latest

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