On 2018-09-27 18:25, Eric Dumazet wrote:

On 09/27/2018 05:16 PM, stranche@codeaurora.org wrote:

quoted

Hi Yuchung,

Based on the dumps we were able to get, it appears that TFO was not 
used in this case.
We also tried some local experiments where we dropped incoming SYN 
packets after already
successful TFO connections on the receive side to see if TFO would 
trigger this scenario, but
have not been able to reproduce it.

One other interesting thing we found is that the socket never sent or 
received any data. It only
sent/received the packets for the initial handshake and the outgoing 
FIN.

Just to make sure : Was this some sort of syzkaller (or other fuzzer) 
run ?

No, this was a normal run.