Bug 123454

Summary: igmp packets generated with invalid cksums
Product: Red Hat Enterprise Linux 3 Reporter: Ion Badulescu <ionut>
Component: kernelAssignee: James Morris <jmorris>
Status: CLOSED ERRATA QA Contact: Brian Brock <bbrock>
Severity: high Docs Contact:
Priority: medium    
Version: 3.0CC: petrides, riel
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
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Fixed In Version: Doc Type: Bug Fix
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Last Closed: 2004-12-20 20:55:16 UTC Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Flags
IP partial-checksum fix for x86_64 none

Description Ion Badulescu 2004-05-18 18:31:18 UTC
From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030703

Description of problem:
This is from tcpdump, when a native (64-bit) application attempts to
subscribe to a multicast group:

14:22:19.150000 10.0.30.20 > 224.0.0.22: igmp v3 report, 1 group
record(s) [gaddr 239.255.0.11 to_in { }] bad igmp cksum ebff! (DF)
[tos 0xc0]  [ttl 1] (id 0, len 40, optlen=4 RA)

I haven't tried a 32-bit application, so I don't know if it would work
or not. I strongly suspect it wouldn't.

The packet is obviously ignored by the receiving router(s), so the
application ends up not receiving any traffic.


Version-Release number of selected component (if applicable):
kernel-2.4.21-15.ELsmp and 2.4.21-9.0.3.ELsmp

How reproducible:
Always

Steps to Reproduce:
1. run tcpdump -vvv -n igmp
2. run any multicast listener (routed/gated would do, but it's not
provided, zebra will probably do as well)
3.
    

Actual Results:  observe the bad igmp cksum message from tcpdump

Additional info:

Comment 1 Ion Badulescu 2004-05-18 19:51:35 UTC
Also look at:

http://lists.suse.com/archive/suse-amd64/2004-Feb/0322.html

for another instance of the same bug, and a proposed solution.

I tested that solution (attached below) and it seems to work for me.


Comment 2 Ion Badulescu 2004-05-18 19:53:28 UTC
Created attachment 100311 [details]
IP partial-checksum fix for x86_64

Comment 3 Mike Gahagan 2004-10-07 15:18:50 UTC

*** This bug has been marked as a duplicate of 131048 ***

Comment 4 Ernie Petrides 2004-10-07 20:16:38 UTC
A fix for this problem was committed to the RHEL3 U4 patch
pool on 14-Sep-2004 (in kernel version 2.4.21-20.6.EL).


Comment 5 John Flanagan 2004-12-20 20:55:16 UTC
An errata 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 the 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-2004-550.html