[Bridge] mac table updates

Dirk Morris dmorris at metaloft.com
Fri Jul 29 09:43:40 PDT 2005


>
>
>>I think the new mac ageing (sometime since 2.6.8.1) may be too
>>aggressive. Now it updates the table at a much later time, with a
>>comment in the code that leads me to believe
>>this is to prevent counting spoofed packets and a DOS.
>>
>>My problem is that the update occurs after the netfilter hooks which
>>may do weird things to change the course of the packet so that it
>>does not get counted.
>>(in my case, redirecting, queueing to userspace, nonlocally bound 
>>sockets, etc).
>>For me this causes packets to go spewing out on the wrong interface
>>when the timer expires.
>>
>>I used the attached patch to revert back to the old method.
>>    
>>
>If you are whacking the source address, that seems wrong.  The fix for
>that would be to copy the original source address somewhere, then
>extract it back afterwards.
>  
>
I think I was leaving the source address, but I was queueing to 
userspace, which causes the packet
to "disappear" from the kernel, meaning the update code was just never 
reached.




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