AIKIDO-2026-562254

TL;DR

quinn-proto's outgoing datagram queue keeps a payload_bytes count of buffered data to bound memory use. When a full buffer evicts queued datagrams, both Datagrams::send and the buffer's own eviction logic subtract the evicted size from payload_bytes, so the reduction is counted twice. Sustained eviction drains the counter past its true value, causing an overflow panic in debug builds or a desynchronization panic in release builds inside send_datagram. The fix removes the redundant subtraction at the call site.