Linux drops TCP segments of a connection that follow a SYN/ACK with timestamps set to 0
Issue
Internet servers responds to SYN sent by our proxy with a SYN/ACK packet that has both timestamps in TCP options (tsval/tsecr) set to 0. While the handshake completes, a future data segment from that server to us is dropped by TCP because it contains non-zero timestamp values, which triggers certain PAWS logic in Linux stack (more details follow).
Environment
Red Hat Enterprise Linux (RHEL) 6.6
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