Re: select() regression in libpcap-devel?

[Guy Harris <guy () alum mit edu>]

On Jun 24, 2009, at 2:21 PM, Guy Harris wrote:

> ...does this happen with standard 1.0?  If not, this might be a side- 
> effect of a bug fix in top-of-tree - it turns out that you are *not*  
> finished with a packet when the callback returns; consider how  
> pcap_next() and pcap_next_ex() are implemented - they call the  
> callback and, when it returns, hand the packet back.  That's not an  
> issue when the packet buffer is owned solely by libpcap, but if it's  
> shared between the kernel and libpcap, the kernel might reuse a  
> buffer slot in the memory-mapped region after libpcap releases it,  
> so it can't release it until the *next* packet is read.

Yup, that was it.  I've backed out that bug fix (checked in and  
pushed); I'll re-fix the bug by having the callback pcap_next() and  
pcap_next_ex(), when the capture is in Linux memory-mapped mode, make  
a copy of the packet and return that.
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