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Prior to this update, the libpcap library filtering mechanism
did not correctly detect the initial network packet if capturing on all
interfaces was requested. As a consequence, the tcpdump utility failed to
capture the initial packet. The libpcap code has been patched to account
for the additional SLL header automatically added by the kernel, thus
fixing this bug. As a result, tcpdump now also captures initial packet.
Are you observing the same behavior on other architectures too? Can you rerun the test but tell tcpdump to capture on specific interface, i.e. eth0 on server? So we can possibly rule out issues with cooked mode. Also try to retest but don't disable promiscuous mode.
It is weird that it works in Wireshark, because it uses libpcap too.
Knowing that it works when capturing on specific interface, is very valuable. Thanks for sharing test results.
Although, so far I have no idea where is the problem. I have to investigate further.
I think I was able to pin down the problem. I started an upstream discussion about the issue. Hopefully we get some response from upstream maintainers soon.
https://github.com/the-tcpdump-group/libpcap/issues/405
My current fix is bit of a hack, I figure that proper fix will be more involved and will require further work upstream.
In the meantime here are the test packages,
https://msekleta.fedorapeople.org/libpcap-1176612/
Seems like this can't be deferred. There was no response from upstream. Though, I was able to come up with "safer" fix for the issue which seems to be working.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://rhn.redhat.com/errata/RHBA-2015-2130.html
Created attachment 972069 [details] packets captured by wireshark