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Bug 682066

Summary: panic on ipv6 udp-fragmentation-offload of bridge device
Product: Red Hat Enterprise Linux 6 Reporter: Masahiro Matsuya <mmatsuya>
Component: kernelAssignee: Herbert Xu <herbert.xu>
Status: CLOSED DUPLICATE QA Contact: Red Hat Kernel QE team <kernel-qe>
Severity: medium Docs Contact:
Priority: medium    
Version: 6.0CC: moshiro, syeghiay
Target Milestone: rc   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-09-19 11:50:12 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:

Description Masahiro Matsuya 2011-03-04 02:10:41 UTC
Description of problem:
The kernel panic occurs if a bridge device is connected with physical NIC and UDP packets are transmitted via the bridge device.

The kernel panic occurs when all the following conditions consist:
- The kernel version is RHEL6(2.6.32-71.xx.el6).
- The NETIF_F_HW_CSUM of the physical device connected with the bridge device is available.
- The udp-fragmentation-offload function of the bridge device is available(ON).
- The udp-fragmentation-offload function of the physical NIC is unavailable(OFF).
- IPv6 protocol
- The size of the UDP datagram exceeds MTU. (fragmentation is necessary)

The system configuration:
Test_program ---> UDP/IP ---> bridge(br0) ---> NIC(eth0) ---> network

Version-Release number of selected component (if applicable):
kernel-2.6.32-71.el6 

How reproducible:
Always with the reproducer

Steps to Reproduce:
1. gcc -o udp6_send udp6_send.c 
2. run reproducer.sh (put udp6_send in the same directory).
  
Actual results:
Kernel Panic occurs.

Expected results:
Kernel Panic doesn't occur.

Additional info:

Comment 12 Herbert Xu 2011-09-19 11:50:12 UTC

*** This bug has been marked as a duplicate of bug 698170 ***